Tuesday, 19 May 2009

It's all about the timing.

We have quite a number of plants in containers in our garden. I get them trade doncha know. Some of them are quite small and being terracotta dry out quite quickly.

Some of the containers, however, are quite large. The back wall of the house was rather plain looking and I wanted to train Virginia creeper over it. The previous owners of the house had installed paving on concrete right up to the house and so planting the Virginia creeper in the ground was not possible. I decided to try an experiment (a long term experiment!) and plant the climber in large terracotta style pots. I used large synthetic ones partly due to the cost but mostly due to potential hernia problems if I lifted them!

I also planted four 8ft tall trees in to large square synthetic terracotta style containers to screen off the side of the garden.

Well, the Virginia creeper is still there after around 10 years and has almost covered the back of the house. It looks beautiful in the summer and turns that lovely deep shade of red in the autumn. The trees are now around 15ft tall and quite bushy. They are stable in windy weather as they are now in square planters. They were originally in flower pot shaped containers but began to blow over in the wind. I had to go out the back on a few occasions to lift them off the floor. If they had been real terracotta they would have turned in to a 3D jigsaw puzzle!

Many years ago we were going away for a few days and a neighbour kindly offered to water the plants. I’m sure he did water them, but it was very hot weather and perhaps he hadn’t quite watered them enough. When we returned from our break, the plants in the containers were wilting in the extreme.

It was at that point that I decided to fit an irrigation system. Every plant pot and for a while, every new tree in the garden was being watered twice daily. Automatically. There is a number of battery operated watering timer kits on the market and they range from the basic once a day to programme for different times on different days of the week.

They are simple to fit and just need an outdoor tap with a suitable anti-siphon fitting to prevent unclean water going back in to the house supply. Fitting the larger distribution hose and smaller feeder hoses is also easy but time consuming, and needs a little planning to avoid unsightly hoses everywhere.

The timers need to be taken inside in the winter as the frost will damage them but the hoses can be left in place. It’s quite easy to forget to re-install the timers in good time as you think spring isn’t quite over but then you feel the soil in the pots and it’s quite dry. Before you know it the trees in the pots are covered in leaves and the Virginia creeper is shooting. Forgetting to water now could lead to ten years of growth dying off!

The experiment has been a success but I sometimes wonder whether I should have arranged for some large holes to have been drilled in to the paving. It’s a bit late now though as the roots in the containers won’t reach the floor if I took them out of the planters. The Virginia creeper may be getting a bit root bound now so I may have to upgrade those planters. It’s going to be fun trying to get the root ball out of the container without ripping off the stems from the wall and damaging them. I will replace the round planters with square ones as they can hold more soil overall.

I have only recently learned that in addition to the terracotta and lead coloured synthetic flower pot shaped containers, you can also get beige, black, brown, green, blue, mauve, red and yellow! Ideal for a funky bar or restaurant.

I get them trade doncha know!

Monday, 11 May 2009

More garden pests

Not so much 'more garden pests' but 'more pests in the life of a plant display maintainer'. Fortunately we don't come across too many pests, but the first incident other than the common or garden greenfly was when one of the girls that worked for me let out a shriek while changing over a large plant in an office. "I've just seen a large beetle in the soil", she said. Thinking it would be a wood louse or something equally innocuous, I dug in to the soil in the plant container only to find an odd looking beetle that looked slightly exotic. I captured it and placed in to a plastic cup when "Oh look, it has a family!" They joined the first one in the cup and were duly packaged off to the Natural History Museum in London.

The museum will happily accept crawling donations, preferably alive, to add to their collection. In return they will identify it for you. It used to be a free service and I think it still is for private individuals but if it a business related find then a charge is made.

It turned out that the creature was a Surinam cockroach. They are not considered pests as they don't usually set up home inside buildings and according to Wikipedia often arrive in houseplants. They were the only ones I have ever seen in nearly 30 years of business.

The next pest incident was originally thought to be a pest of a different kind. A member of staff kept asking why the security guards in one of our buildings were nibbling her apples that were left in the van. The van keys were always left with security. The guards kept telling her that they didn't do it but as they said it with a smile on their faces, she didn't really believe them.I had a box of Christmas decorations in the back of their van and opened it one day only to find that some of the decorations had been shredded.

This puzzled me for a while until it dawned on me that the secret nibbler could well be whatever is nestling in the box. I took all the decorations out and found the tiny apple lover, a field mouse, at the bottom!

It was well over a year ago that I opened up a packet of tropical flowers in an office when a small pink frog jumped out. Using the trusty plastic cup method again, I captured it and put it on an overgrown grass verge in a nearby car park. Returning to the office, I opened up another packet of tropicals and lo and behold another frog! Sadly, this one was dead. One of the cleaners that worked at the building came from South America. He was nearby when I took the frog outside. Shortly afterwards, I saw him rubbing his bosses pen on the back of the frog. Goodness knows why the cleaner would have even touched the pen as it was always in his boss’s mouth!

One week I found a leech in some tropicals. I quickly sent it surfing down the toilet in case it had Nile fever or something. I was in the tropical flower department of one of my suppliers a week ago. Two of the guys that work there were looking at something in a jar. "What is it?" I asked. " A tropical spider" they replied. As I looked at it, I asked whether they were sure it was tropical as I had one like it riding along in the cab of my van a short while ago. I could see it was the same type by the way it tucked it's legs neatly together. " It's definitely tropical!" came the reply. Hmm.
I tried to look up that type of spider on the internet and came up with a possibility: the Nursery Web Spider. Without seeing one again I can’t be too sure but my passenger had its legs together in a similar way to the one in the picture. It’s an image I found on Google, that’s not my tyre it’s resting on!

Just as you can misdiagnose your symptoms on the net and think you have Parkinson’s AND Motor Neurone disease when in fact you have just been gardening too strenuously, you can also wrongly identify creatures. For a while I though my friend might be a Brazilian wandering spider due to an image having that description on it. I don’t think it is after all but reading how poisonous the Brazilian spider is I got a little paranoid. Rinsing some dishes, I saw some large spider legs coming up through the bubbles, then realised it was a stem from some grapes! Phew!

I'm not normally concerned about spiders and will happily pick them up. My lack of fear is all down to a boy I went to school with: Dennis Hall. He was showing the girls a spider he had in his hand and not to be outdone, I picked one up too. It was only later on that I realised Dennis's spider was a dead one!

Saturday, 9 May 2009

Silicone moulds for GRP plant containers.

Silicone rubber is often used as a moulding material usually where minute surface detail is required. There is virtually no shrinkage and it is recommended for when a larger number of casts are required such as plant containers.
There are many types of silicone rubber available and this article gives a general introduction to its use.

Mixing and Mould Preparation

The resins used for the products made in silicone rubber moulds can reach a temperature in excess of 160ºC and after the mould is made it should be left to cure for at least 24 hours.
Post curing of the silicone mould for a further several hours at 10ºC higher than the curing temperature of the resin may also prolong the mould life.

Master patterns are made from the shape that you want to copy. The pattern can also be designed and produced by specialist companies. The master shape must be firm enough to be painted with Silicone and has to be prepared with great care, as all surface defects will be reproduced on the finished item. Master patterns made of porous material such as wood, plaster or stone can be sealed with a sealant. If the surface is then polished with a release wax, a high gloss will be imparted on to the silicone mould. Other release agents that can be used are petroleum jelly and polyvinyl alcohol.

A Simple Open Mould

A mould box is used to fit around the master shape. For a custom built square planter it can be made from wood or cardboard or similar stiff material. Any gaps between the floor of the mould box and the master shape should be sealed with Newplast or Newclay. The area under the master shape will eventually be the hole through which the resin is applied to the inside of the finished mould. The mould box should then be coated with a fine layer of petroleum jelly or mould wax.

The silicone rubber in liquid form is activated by the addition of a curing agent which is stirred in to the silicone by hand using a flat stirrer. A disposable vessel is used for this. Extreme care should be taken not to stir in any air, although stirring must be thorough to ensure a complete mix of the two components. It is recommended that the material is “degassed” after mixing by using a vacuum chamber, as it is very difficult to remove air by any other method. If a vacuum chamber is not available paint over the surface of the master pattern with a thin coat first of all to obtain an air bubble free layer. Working time for the mixed silicone is around 30-40 minutes at room temperature.

Allow to stand for approximately 10 minutes before pouring the remaining silicone in to the mould. Hold the container as low as possible and pour in a thin stream. Leave to cure for 24 hours before removing the mould.

Making the product

A release agent is applied to the inside of the silicone mould to stop the fibreglass from sticking to it. For simple moulds the surface is coated with PVA (polyvinyl alcohol) release liquid. For larger or complex moulds, a two stage parting compound of non silicone wax and PVA is generally used.

A special resin called gelcoat is always used as the outermost layer in fibreglass moulding. This un-reinforced resin coating is at least 0.5mm thick and provides a smooth, glossy, protective and decorative layer between the glass fibre and outside moisture. It is often coloured with a pigment paste. At least 4 hours curing time must be allowed to prevent the solvent in the next layer of resin from wrinkling the gelcoat.

When the gelcoat has cured, it is coated with lay-up resin. The first layer of chopped strand matting made of fine glass fibres is applied. In order to fully impregnate the glass fibre with resin, a paint roller or brush is used, stippling the brush over the fabric to avoid dislocating the glass strands with the sticky, resin coated bristles. This is known as consolidating. The process is repeated to build up a strong layer of GRP (glass reinforced plastic).

When sufficiently cured, the moulding will be slightly shrink away from the sides of the mould, this process is assisted by dissolving the blue release agent with water poured along the edges. The final product is now finished.

Repeat this process thirty or so times until the order for the plant display maintenance contractor is ready!

Plastic is not a nasty word!

The term plastic can be both a noun and an adjective. Plastic, the noun, refers to a wide range of synthetic materials that can be moulded in to shape. Plastic, the adjective, means that the shape of the material in question can be deformed permanently without fracturing when a force is applied. It means, therefore, that some plastics are not plastic.

Types of plastic (the noun) include vynil, polyethelene, epoxy resin and butadiene-rubber to name but a few. There are at least thirty different types and everyday ‘quality’ items such as computer casings, shoe soles and up-market car engine bay parts are made from them. So plastic is not really a cheap and nasty material at all. It is, however, a cheap material when mass production is considered as once the initial mould or former is created, the item can be reproduced many times over.

Plastics are formed into shapes in many ways:

Hot molten synthetic material is forced through a nozzle to produce lengths of special shapes like tubes and angled strips and sections for joining board materials, protective corners, kitchen cupboard door handles and guttering.

This is used for making plastic films and bags. While still hot and malleable, an extruded tube is inflated like a balloon. This stretches and thins the plastic. The inflated material is produced in such a length to allow the plastic to cool. The end of this ‘balloon’ is sealed with a roller mechanism to retain the air in and to flatten it. This cooled flattened tube is then wound on to a big roll.

Hot molten synthetic material is injected into a mould to mass produce everyday items. The parts produced can be very small like a washer or large like a car part, dustbin lid or some planters.

A small amount of hot malleable synthetic material is injected into the end of a mould. Compressed air is used to inflate a ‘bubble’ inside the plastic. The plastic material swells and fills the mould. This method is used to manufacture bottles and some toys.

Plastic powder is scooped into a former. The former or mould is rotated over a heat source. As the mould increases in temperature, the powder melts and sticks to the inside of the mould. This method is used for large round items such as plant containers and water barrels.

This method uses thermoset resins. These are resins that will not melt when reheated after manufacture. A dry powder is placed in a former which is then compressed and heated until the resin has cured. This is used for making ashtrays, plates, and electrical switches.

A resin and hardener are mixed and injected in to a former. The materials react and combine to form a hard material used in car parts, bumpers and plastic food trays in supermarkets.

A sheet of plastic material is held in a frame and heated until flexible. A vacuum pump then draws the sheet into a former. Packaging for many consumer goods is produced this way.
Plastics can be made in to other shapes by fabrication. That is to say two shapes moulded in one of the above methods can be jointed with the application of heat and additional plastic to form a more complicated shape. There are other ways of manufacturing consumable items and these include GRP (glass fibre), wood machining, metal machining and metal moulding but plastic is usually the most economical. There is a large range of plant containers available made in all of these materials in various styles and colours.

Plastic is not a nasty word. Plastic is in fact a wonderful material!

Thursday, 7 May 2009

Garden pests.

I am a cat person. I don’t mean that I have whiskers and a long tail and lick my, erm, fur. I mean that I have had cats for years. For the sake of impartiality, I love dogs. It’s just that cat’s are easier to maintain.

Like a child with a new savings account, cats leave small deposits. The thing is, these deposits don’t gather much interest. Like a Swiss child with a new bank account, the deposits are usually buried deeply and are not easily seen. The problems began when my sister’s cat came to lodge with us. He is a lovely, affectionate and playful cat but I’m sure he is reincarnated. In an earlier life he was an Apollo astronaut as he loves to recreate moon craters in my flower beds. No other cat that I have been a servant to has done this. TC must also be an amnesiac as he forgets to move all the soil back in to the hole he has just created. I’m sure I saw my elderly next door neighbour pick up and try to light a large cigar he had found on the grass. I hadn’t the heart to tell him!

I didn’t see any tulips in my garden this year. TC removed them. I planted some spring bedding plants. TC removed them. This is a daily (or nightly) occurrence. He even does a balancing excavation act on 12” diameter terracotta pots, one of which had sticks in AND cotton twined around.

I have just taken out the remaining plants as they were looking a little sad where the exposed root balls had dried out in the warm weather. There is now a nice blank canvas for TC to perform his horticultural arts.

I will be setting up my flower bed irrigation system soon and hopefully this will deter him as the soil will be more moist and potentially less attractive to dig in. I haven’t tried pepper dust as yet but I did try citrus peel with no success. It tends to look rather unattractive too. I had great success with some small brown garden stakes intertwined with cotton. The cotton is heavy enough to annoy the cat as he tries to walk through it but not strong enough to cause entanglement problems.

I have covered the tops of the stakes with little ‘test tubes’ for safety. There is nothing worse that the proverbial poke in the eye with a sharp stick and sticks seem to be invisible when you are near them. The ‘test tubes’ used are a little water reservoir for Anthurium flower stems and I usually have quite a few of these hanging around.

I had an early set back with the cotton method though. A neighbour’s cat likes to come along to our house on a regular basis and bully our cats. I had just popped indoors after setting up the first lot of cotton and stakes. The neighbour’s cat was by our open front door and when I went to go outside again, he felt guilty at trying to creep indoors and ran out the door, turned left as all felons do and went straight into the cotton at high speed. He just carried on moving but the neatly lined up cotton was totalled. I repaired it though and it and it worked well for all the time it was there.

Dead-heading flowers was a bit of a pest as you couldn’t see the cotton and it would sometimes break it as you move your hands around the beds.

I have read articles on zoo poo here and there. The idea is to leave dung from predatory animals in the flower beds whereupon cats and deer instinctively avoid these areas. There is a wildlife park just up the road so obtaining the product shouldn’t be a problem but I wondered how you get the lion or tiger to sit just over your flower beds. If you try to shove them in the right area will they bite? If you leave them to it will they run off? Do they dig an even bigger hole themselves and then what do you do. I am not as tough as the old lady in the Madascar movie and don’t fancy saying “bad kitty!” to a 400 lb predator!

I will set the sprinklers to full on and use the cotton and stick method too. When the flowers become established and no soil is visible I shouldn’t have the same problem. Or will I?

Tuesday, 5 May 2009

Light up your life!

April. It’s that time of year again. The garden may have been a little neglected through the winter and indeed you may not have even set foot out there for months but as soon as the sun shines we are out mowing the lawn and trimming the brambles that have crept through from next door. How is it that they have been growing during the cold weather when everything else hasn’t? The plants in pots will need watering, and the daffs will have flowered and faded already. If you lead a busy lifestyle you will have probably missed them. The grass is growing quite quickly now. “Hey, I just cut that. How come I need to do it again?” The garden is tidy, the furniture has been cleaned and if you are really efficient, the patio will have been pressure washed.

It may also be time to consider buying a new barbeque as the grey fur on the blackened grill bars looks a little unattractive. That piece of chicken left there in August is no longer edible. I personally find that the disposable barbeques on an attractive purpose made stand are far better than watching the expensive model turn rusty. They all do eventually. The disposables also reach a usable temperature more quickly. How many of you have cooked the food on the flaming barbie and finished it all off as you then turn to see the charcoal reach a perfect temperature? Then there’s the cleaning of those grill bars!

You may already have installed lighting in your garden and if the more basic sets have been left out over the winter they will probably need new bulbs, repairing or even replacing. The solar powered models aren’t quite as bright as the pictures would have you imagine so you consider a new set. For convenience you may consider a ‘plug and go’ set which has a transformer and 12v lamps attached to low voltage cable. The advantage is convenience but as soon as you try to run a longer cable to reach the far end of the garden, you realise that the lamp the furthest away has little more than a dim yellow glow. This is caused by voltage drop where the voltage at the lamp end of the cable is lower than the voltage at the power source (the transformer) and is due to resistance in the cable. As the supply voltage is quite low (12v) any voltage drop will be quite a high percentage of the supply voltage and the circuit will not operate efficiently. Technically, to reduce this loss the diameter of the cable or the voltage can be increased. For a long run, a cable with a large enough diameter will not be suitable and so the only practical answer is to increase the voltage.

The best method for a long run of lighting is for a qualified electrician to run an armoured mains cable to suitable points in the garden and fit transformers in weather proof enclosures. Low voltage lamps on a short length of low voltage cable can be fitted and positioned where necessary and there will be no appreciable voltage drop. You can have as many lamps as you want, including uplighters or spot lamps, in any position you want without the problem of dim lights and without the risk of electric shock. While you are going to the effort of having the mains cable installed, you can also have suitable connection points fitted for a pond pump or fountain and even illuminated planters. Instead of the usual plant containers with a lamp on a spike stuck in the soil, the very plant container itself will light up! These are mostly suitable for a contemporary garden design and can also be used indoors.

Flying saucers fly though office windows.

Within the next few months there will be an upsurge of flying saucers. Attempts will be made to retain some as they are clearly recognised as belonging with others of similar colour and appearance. Most of them will be destroyed. Destruction is probably the best option as there is nothing more unattractive than a beautiful plant standing on a tatty saucer from a defunct tea service.
The upgrade from the tea service saucer is the ‘official’ plant pot saucer available in forms including terracotta colour, green and the naughty see-through. There is a further upgrade from this: the pot cover. This is usually a coloured plastic, ceramic or metal cover that hides the basic flower pot. It has no drain holes and this does away with the need to stand the Azalea on Aunt Millie’s old chinaware. Pot covers have a bit of a drawback in that the plant in its original basic flowerpot may be a little root bound. Watering the plant causes the water to run through the almost soil-free roots and collect in the bottom of the pot cover. Even with plants that are not root bound, overwatering may result. The roots will then be sitting in water which for most plants is undesirable and leads to rotting of the roots.
There is a solution. Your lovely Spathiphyllum can be planted in to a proper plant container. A plant container with some extra soil in will allow the plant’s roots to grow and the foliage to flourish. There is now an enormous range of plant containers or planters available and these are supplied in a range of sizes from a few inches in diameter to several feet wide for trees.

Like the pot cover, the materials that the planters are made from vary. The most common are timber, plastic, ceramic, metal and GRP ( glass fibre ). There is a newer material available now called AC or Advanced Composite fibre. Similar to GRP, this technology combines resins with high-tech woven materials that can be formed into almost any shape. AC is used in the aerospace industry, motorsport, medical scanning equipment and the undersea industry and now of course the plant display industry.

Advanced Composite fibre containers - chrome style finish

The shapes and colours that the new plant containers come in are amazing. Textured finishes to simulate wood, streaked copper, old lead or rusted metal is easily achieved. There is even a finish that looks like chrome plating. The AC containers are much lighter, cheaper and sometimes stronger that the original material and are fully waterproof avoiding staining on floors or carpet that sometimes occurs with a leaky timber or metal planter. Gone are the days when the plants for the office were available in any colour as long as it’s white!

Late planting of Spring bulbs

The standard advice for planting spring bulbs is to plant in the autumn. Surprisingly, against the advice of gardening experts, as a landscape contractor I have been planting daffodils and tulips in February for many years. One of the reasons is that a local retail nurseryman would sell spring bulbs until a few weeks before Christmas. He would then want to clear out his remaining stock to make room for Christmas trees, poinsettias and seasonal plants and flowers. In order to clear the remaining stock quickly and would offer them to me at a price that was lower than cost provided I had the lot. The danger was, of course, that there wouldn’t be enough of the right type of bulbs. This was a risk I was willing to take and that risk was ameliorated by buying a number of tulips and daffodils from normal trade suppliers.

Another reason for planting late was related to the late planting of winter flowering bedding. I would try to leave the impatiens in for as long as possible. After the beautiful summer bedding is removed, it is usually a good idea to have bare soil for a couple of weeks. The flowers on the winter bedding: pansies, cyclamen and primula cover a much smaller area than those on summer bedding. Planting winter flowers immediately after the summer flowers have been removed leaves an impression that something is missing. The two week period is enough for people to appreciate the return of some colour.

So, the winter flowers are going in late, customers are ordering Christmas trees and these have to be installed in their offices and decorated. There is no spare time to install bulbs now. There is another factor delaying proceedings. In some gardens with a large number of deciduous trees, despite being cleared on a weekly basis the leaves hang around until after December. Planting bedding before that time makes it more difficult to clear out the enormous quantities of leaves. It is not practical to plant bulbs early, wait until the all leaves have been removed and then plant winter bedding. If you do this, the firm bulb shoots often spear the root ball of the winter bedding plants and lift them clean out of the ground!

The right time to plant bulbs for me was in January. With other matters to attend to, this often slipped in to early February. The drawback of this method is that the bulbs flower one or two weeks later than everyone else’s. The benefit is that you have something to look forward to when bulbs in other gardens have finished. In addition, if the winter is a particularly wet one, the bulbs that are planted early may rot and not shoot at all.

Further expert busting tips: don’t worry about planting all tulip and daffodil bulbs the right way up. When you have around 5000 to install that seems a little too much to think about. For areas with no bedding plants dig a small trench, not too straight, around 2ft long and 1ft wide. Throw in a load of bulbs so that the bottom of the trench has bulbs all over but only one or possibly two bulbs deep. Ignore advice about turning them the right way. Cover with soil and water in. Move along a couple of feet and make another different shaped trench and so on. When planting in areas with bedding plants, dig a small hole around 3-4" deep in between previously planted bedding and drop in 3-5 bulbs. Cover with soil and water in. Gardening contractors shouldn’t plant too deep. This makes it much easier to remove them after they have flowered. They are not left in the planted beds in office gardens for the following year as the foliage looks unattractive after they have flowered. If they were to be left until the nutrients have gone back in to the bulb, there would be yellowing leaves until June. They also shouldn’t be planted so that the whole bed is covered. Groups of flowering bulbs of the same colour look more attractive than an area that is totally covered, unless you are planting flat regular shaped beds like the local authorities still do. For gardening contractors, new bulbs every year is the general rule. For contractors and home gardeners alike, don’t forget to water the tulips and daffs in raised beds and pots. The warmer weather causing the flowers to open is also drying out the soil and if they are not watered, the foliage and flowers will droop and look straggly.
Finally, if you didn't get around to buying bulbs in the Autumn, pot grown daffs and tulips can be planted in your garden from January to March. This is an expensive way of doing things but allows you to brighten up your garden if you have a special event. Pots grown bulbs will last for a few weeks so it's still money well spent.

The basics of indoor plant maintenance

I remember an old aunt, now sadly no longer with us that used to survive on a cigarette for breakfast, lunch and tea. She didn’t take care of her body but she was a dab hand at looking after plants. There may be no scientific basis for the term green-fingered but Auntie Grace seemed to have the magic touch. Her apartment was stuffed full of odd cuttings that she was given or had taken from other gardens. She would almost throw the cutting in a pot and the next time you saw her, the plant would have grown to twice its original size. Did she have green fingers or were the plants all thriving on the toxins in the smoky atmosphere? Auntie Grace’s apartment was very well lit with large windows on both sides of her living room. That is one of the obvious but often overlooked requirements for most pot plants. “Why is my plant dying?” I am often asked. “Where is it in the house?” I reply. “On the television.” It often turns out that it’s a position well away from a window. There are plants like Philodendron scandens and Scindapsus that will tolerate low light levels but as these are usually the ‘plain green’ varieties and pot plants chosen are usually flowering or more colourful and need plenty of light. Plants really should be placed in a bright spot near a window although the light should be filtered through a net curtain or be in a window that doesn’t get direct sun. Direct sunlight will scorch the leaves.

The other obvious (to some) factor is watering. I have known people to mention that the plant has died or is withering only to discover that it hasn’t been watered for several weeks. Others say that their plant at home is watered every day and is now beginning to die and smells a bit. This also happens with office plants where tea, coffee or other waste drinks have been poured in to the plant container. “I have been watering it a bit.” Oh, dear. Too much water this time.

Two classic plants that are subjected to over watering are the rubber plant and the Yucca. With both plants, yellow leaves may appear. The owner thinks that they are not watering enough so on goes more water. More yellow leaves appear, are you beginning to get my drift? Unless they are placed in a very warm, bright position they need only a minimal amount of water. A quarter of a cup per week is often enough. There is a digital method for checking how moist the soil is in the pot. When I say digital, I mean that you should stick a digit ( finger) down into the soil to see how moist it is. If the soil is dark and sticks to your finger it’s probably moist enough. If it looks light coloured and is powdery, the more water may be needed. Another method is to feel the weight of the plant. If it is very light in weight it could be too dry. Check it in its dry and moist state to feel the difference and you will have an easy way to know whether you need to water or not.

Instead of simply pouring water in to the pot cover or plant pot, it is best to sit the whole plant and pot in a bowl of water and give the soil a thorough soaking for half an hour. Avoid wetting the leaves of African violets as they will discolour. Make sure the plant is thoroughly drained before replacing it in its pot cover and remember that plants away from a bright window position will not need to be soaked like this very often.

Finally, there will be the odd leaf that turns yellow. Simply pinch it off or snip it off with a pair of scissors. Those are the very basics. The plant will last for years with this very basic care. Larger plants can be properly planted in to a suitable container with some additional compost to prolong their life. Some containers even have a self-watering unit. This is a water reservoir with a level indicator and filling tube for ease of watering.

Do you hire flowers?

I am often asked whether I am able to hire out flowers for weddings and events. “Of course!” I reply, but I have to qualify that statement. Artificial flower hire is available, but fresh flowers for vases, arranged in Oasis or made in to a bride’s bouquet have a limited life. If companies were to hire this type of flower display at a cost which is lower than the normal purchase price (which is what hiring is all about) then they would be making a loss on every contract! Beautiful flower displays at reasonable prices are available but this is on a purchase only basis. It is, however, possible to hire flower displays which are a slightly different kettle of fuschia. Sorry!

Flower displays are tropical plants, trees, and shrubs either placed in groups or planted in a suitable container with the addition of flowering plants. The flowering plants can be pot grown or can be added to the display by placing them in Oasis. Flower hire as described above is much more economical for a given quantity or volume when compared to fresh flowers, probably around a third to a half of the outlay. Apart from the cost of the actual flowers which are often imported (see below) the labour cost is high as it takes quite a bit of skilled labour to make an attractive flower arrangement. In some cases the completed fresh flower display has to be attached to posts, pillars and canopies and fixings and fittings are all costs on top of the flowers. Admittedly, the flower displays may not look as stunning as a large quantity of fresh flowers and if your budget allows go for the flowers. You will make the supplier very happy! The very fact that the word budget is mentioned means for most people that there is a limit on expenditure.

You don’t have to go with one or the other, of course, and you can have fresh flower arrangements for the tables and plants and flower displays placed around the outside of the room and in strategic places. Water features can often be added for great effect.

Mentioning imported flowers earlier, some flowers travel enormous distances. Examples are: carnations and roses from Venezuela ( 5000m ) and Chile ( 7500m), protea, roses and exotics from South Africa ( 6000m ) and orchids from Thailand ( 6000m ). Flowers are harvested in the cooler morning hours in order to give them a longer vase life. They are then cooled to less than 60F within the hour and stored at temperatures between freezing and 40F. Flower markets are often in the same location as fruit and vegetable markets. It is interesting to note that ethylene gas is produced by stored fruit and veg and this is detrimental to cut flowers, particularly carnations and delphiniums and so care is taken to store the fruit and flowers away from each other.

Cost/benefit analysis of office plants

Plant display maintenance is probably the least costly service available to building management but due to the perception that plants are a luxury item, this service is one of the first that facilities managers cut back on. This is especially so in the current economic climate. Unless the density of the planting is excessive, the actual cost saving made is minimal and the loss of the environmental and indirect financial benefits far outweigh the gain on the accountant’s spreadsheet. So what are the costs involved? A large plant display, say 5ft tall (1.5m) costs around £1.25 plus vat per week to maintain. For that price, the customer gets weekly visits for watering, cleaning, removal of dead or dying leaves and, if need be, pest control. Now here’s the no brainer part. The outlay of £1.25 also covers the cost of replacement plants when that plant dies due to natural causes. Yes, that’s right. For a maintenance service of only £1.25 plus vat per plant you get free replacements for ever! Naturally, the contractor will charge if anyone falls on top of the plant after a lengthy business lunch and squashes it flat. This is an unlikely scenario, however, as business lunches have also been cut due to the economic crisis.

What are the benefits of having plants in the office? Firstly, aesthetics: lush green foliage adds the perception of luxury leading to the presumption that the company is successful. Secondly, environmental: plant displays can have a calming effect, reducing employee stress. Studies by NASA have shown the certain plants remove toxins from the air and have a beneficial effect on staff morale. Increased staff morale means increased productivity and a reduced turnover of staff. A reduced turnover of staff means a reduction in recruitment and training costs. How much would that £1.25 plus vat per week (probably divided between five or six members of staff) have saved so far? Well the cost of recruiting a new member of staff can be between £ 4000 and £16,000.

Let’s do some sums. Say you have twenty plant displays in your office. That’s an annual maintenance cost of £1300 plus tax. Cancel that contract and you have saved £ 1300. Excellent! Not. When the staff return to work after the weekend (and the plants will usually be removed at the weekend to avoid a rebellion) they will notice that one of their indirect benefits has been taken away. Seeds of discontent are sown. One of the team notices that things aren’t going too well and they start to look around for a new job just in case redundancies are made. They may want to be one of the first to leave so that they can get the new job before anyone else is interested in it. As it happens, the firm announces that no redundancies were going to be made as yet but the staff member decides to leave anyway. Cost of recruiting new member of staff: minimum £4000. Savings made on cancellation of plant contract £ 1300. You do the math! You don’t have any plants in the office any more so your recruitment costs are likely to increase.

Happy office/ Sad office

Moral of the day: keep the plants, keep the staff, keep your money! A selection of the types of plants and flowers available for the office can be seen here: http://www.plantdisplayhire.com/ and plant containers or planters can be purchased online at http://www.plantcontainershop.com/.

Eating your office plants: don't!

DO NOT attempt to eat your office plants. The list below shows that there are some varities of plants that can be eaten and some of them are found in plant displays in offices. This is not an advice guide but merely a light-hearted list of office plants that technically could be eaten.

Acer palmatum

The Acer palmatum (Japanese maple) is a decorative tree with small, five lobed leaves. It is frequently planted in office gardens due to its attractive appearance and smaller size. The sap from the tree can be used to make drinks or as a sweetener although it doesn’t contain as much sugar as the Acer Saccharum, the sugar maple. It’s the latter tree that Maple syrup comes from and the sugary sap is collected by making a V-shaped incision in the bark and inserting a funnel directed in to a collecting vessel. This is a slow process and has been made less labour intensive in some areas by inserting tubes directly connected to collecting sheds or sugar shacks.

Dracaena (Cordyline) terminalis

The Dracaena terminalis (Dragon tree or Ti plant) is often used in office plant displays as its vivid red colour provides a contrast to the mostly green vegetation suitable for interior landscaping. In its natural habitat the roots are baked and eaten as a dessert and the leaves can be used to wrap other food prior to cooking. The baked roots macerated in water produce an alcoholic drink when fermented and the dried leaves can be used for roof thatching or for clothing.

Brassica oleracea

The Brassica (cabbage) is not normally associated with ornamental gardening, but can be used as a decorative plant in office landscaping and indoor flower displays. A compact rosette of leaves with frilly edges comprises pink, purple and cream colouring. A long stemmed variety is used in fresh flower displays. In this case the term ‘fresh’ could be a bit of a misnomer as the water in the flower arrangement will quickly turn yellow and give off a stewed cabbage smell. Not popular among receptionists!


For a drought busting garden, one with a Mediterranean feel or a containerised display, Agaves (California cabbage) are a tough albeit expensive choice. The heart, which is the centre after the leaves have been removed, of one variety of Agave (Weber’s Blue) is used in the production of Tequila. Office party animals please note that it takes between seven and ten years before the Agave can be harvested. Agave sap or syrup can be used as an alternative to sugar in cooking. You should be aware that the sap of some Agave will give rise to a painful skin irritation.

There are hundreds of species of Allium, some edible and some purely decorative. Edible varieties include garlic and onions. All have firm erect flower stems with a rounded inflorescence. Allium sphaerocephalon, and Allium caeruleum azureum look elegant in vases although like the cabbage can be a little too fragrant after a short time, with a more than faint aroma of onions.


Some Rhododendron (variety name Rhododendron) flowers are edible although extreme caution should be taken as many of the parts of the rhododendron are poisonous.

Monstera deliciosa

The swiss cheese plant, another very popular office plant, is named so because of the holes which appear in the leaves. Even in the office environment it produces a fruit from time to time which can be edible and is supposed to taste a bit like pineapple or possibly bananas. It definitely does not taste of cheese. The fruit has to ripen for over a year before it can be eaten as the unripe fruit can cause irritation in the mouth.

Helianthus annus

The sunflower is a favourite plant among children due to its ability to grow easily and quickly in the garden. Used in cut flower displays in the office, its flowers taste slightly bitter although you can lightly steam the petals to reduce the bitterness. Unopened flower buds may be steamed like artichokes, and of course the seeds can be bought in packets from the supermarket and are an excellent source of vitamins.


Certain yuccas will survive indoors in a bright sunny position. They will also tolerate low temperatures and so are ideal for conservatories, although direct sun will scorch the leaves or at least turn them pale. The flower petals on some Yuccas may be eaten but edible yucca fruits come only from the thick-leaf yuccas. The variety used in indoor plant displays ( Yucca elephantipes) does not usually produce flowers and is not edible.

There are a whole host of plants in containers, office flowers and outdoor plants in office gardens that may be eaten and a search on the internet will find lists and list of them. You will also find lists of plants that are extremely poisonous and should be avoided at all cost. Do not eat your office plants!

When fake is better than the real thing.

Fake. The word usually implies ‘not as good as’ but the true definition is not as derogatory as you may think: fake means not genuine but not necessarily poor quality. There are fake handbags that are inferior to the original but still used and loved by the owner and fake watches that keep very good time. There was one instance where a counterfeiter was producing fake computers with a popular brand name on the machines and boxes and there was even a working support telephone line! There are also lookalikes that are produced with a similar name. A hand held games console that looked very familiar was called a POP console and a shop sold trainers with a familiar leaping logo bearing the name Pama. In most cases though, fake products are not made to the same standards as the original.

There is, however, a selection of ‘fake’ products that have many advantages over the real thing. The products in question this time are plant containers. Advances in technology now allow high tech materials such as carbon fibre to be added to a resin to make moulded shapes that imitate ceramics, timber, stone and even metals. The advantages are weight, and water tightness when compared to ceramic and in addition durability when compared to timber. In many cases there is a cost saving to be had.

GRP ( Glass reinforced Plastic ) and AC (Advanced Composite) plant containers are available in a wide range of styles and sizes.

There are even artificial rocks made in the same way although these tend to be more expensive than the real thing and the only real advantage is weight. The containers are produced in almost any colours and they will not fade with time. The GRP containers contain chopped strand matting made of glass fibres and the AC planters are made with a woven mesh. AC materials are used in space and undersea applications and also in medical equipment.

Ceramic style AC plant container

Removing lead from contaminated soil.

Lead mining existed as long ago as 6000BC. It became commonly used in jewellery as it is more malleable than many metals. Toxicity problems associated with lead became apparent as early as 200BC when colic and gout was blamed on leaden drinking vessels and white lead used in make-up. Most health problems though, came from lead dust caused by mining. The miners’ symptoms of chronic lead poisoning include neurological problems, such as temporary reduced cognitive abilities, gastrointestinal problems, hair loss, insomnia, reproductive difficulties and in extreme cases seizures. Although the Romans used lead pipes for plumbing ( the word plumbing comes from the Roman word for lead: plumbus) this was not a major cause of lead poisoning as the hard water in Rome coated the inside of the pipes with calcium.

Lead poisoning in the last century or more was largely caused by industrial processes and airborne lead particles from car exhaust fumes. Lead accumulation in soil is partly due to the airborne particles and partly due to lead in paint flakes being deposited over time. The control of the use of lead in paint and the removal of lead additives in petrol by the western world reduced soil contamination although some countries continued to use leaded petrol for many years.

Soil contamination is still a major cause for concern. Lead remains in the soil for hundreds if not thousands of years. Children are most affected by contaminated soil as they are most likely to be in contact with it during play and will even ingest it. As with affected adults, intelligence is impaired and this may become permanent if the contamination is high enough or prolonged. There are concerns that the lead from the soil will migrate in to food crops but studies of lead contaminated soil have shown that the fruit of crops contains far less lead than the foliage, although root crops may be contaminated by the presence of soil dust on the surface. Leafy plants such as cabbage and lettuce are of concern. Lead levels remain high in the soil and lead is not taken up by the plant if the the ph level is high and there is organic vegetable matter in the soil.

This may seem unimportant to the homeowner who would think: “why plant crops in contaminated soil anyway?” but the very soil in your garden may be contaminated if there is an older building or shed nearby that will have been painted with lead paint at some stage in its history.

“How will I know if there is lead in my soil?” There are many lead testing kits available on the internet. If the soil lead level is too high there are a few ways in which you can reduce the likelihood of plant contamination. Firstly you can add lime to keep the ph levels above 6.5. This reduces the amount of lead taken up by the plants. Add organic matter such as leaf compost, manure and peat substitutes as organic materials combine with lead to make it less available to the plant. If contamination is high it may be necessary to physically remove the top layer of soil and replace it with new uncontaminated soil. Finally, grow food crops away from roads and buildings where lead paint may have been used. In addition to the above suggestions for reducing the uptake of lead, don’t forget to thoroughly wash the fruit and vegetables as the soil and dust on the surface of the fruit or vegetable may be contaminated.

There is another method for lead removal: bioremediation. There are plants that are very successful at removing cadmium, copper and zinc but lead removal has proved to be more challenging. It has been discovered that certain grasses have proved to be promising and the grass that has the highest uptake of lead is Vetiveria zizanioides. The grasses, which have little decorative value, are planted in the polluted area and then harvested and removed. The plain appearance of this unassuming plant hides a multitude of talents and in addition to its lead removing properties, vetiver oil is antiseptic and can be used for cosmetic and medicinal purposes. The roots can be used for basketry and screen making.

Below: faux lead planter

We have discussed removing lead from soil. We have been accidentally adding lead to our gardens over many years by pollution and with the use of lead paint and indeed have actually added lead on purpose in the form of lead planters. Decorative lead planters were associated with grand country houses and period properties. Little did those proponents of container gardening realise that they were actually poisoning the very earth they cherished. Lead planters are still available today and apart from the toxicity problem they are prohibitively expensive. There is a lead free alternative, however. Lead style planters made from faux lead (actually made from GRP or glass fibre) in the style of the classic containers can be purchased from leading landscape contractors. The classical style and beauty is retained without the inherant drawbacks. They can also be used as water tanks or rain butts.

Planter, heal thyself!

Most of us are familiar with the term glass fibre and associate it with car body repairs or roof insulation. Glass fibre actually refers to the fine glass strands that make up the matting that is combined with a resin for car repairs or made in to a thick blanket for insulation. The reason that users are advised to wear gloves and eye protection is that the glass fibres are so thin and sharp they can and will penetrate the skin causing irritation. The complete material used for car repair an parts is properly known as GRP (glass reinforced plastic).

A further development of this has been AC or advanced composite materials. As with GRP, a strong mesh is combined with resin to form a shape but the mesh is a high tech material such as carbon fibre. This allows for the manufacture of intricate shapes. Advanced composite materials are used in undersea exploration and in space. They are also used in lower tech manufacturing such as car parts ( bumpers, door skins), ATM machine fronts, fairground rides (vehicles, animal shapes, pay kiosks) specialist vehicle bodies, building construction forms, building accessories ( canopies, dormer roofs), water tanks and transportation and plant containers. Both types of composite materials are durable, strong and lightweight.

It is inevitable, however, that impact damage will result at some stage especially with composites used in vehicles. The damage can simply be cosmetic, though if the damaged area is large enough the impact can have structural implications. Repairing damage to GRP and AC in vehicles is possible with the damaged area being replaced with new mesh or matting coated with the resin. The repaired section is abraded and filled until a smooth finish is achieved. Access to the affected vehicle part is usually easy. Impact damage undersea or in space is a different matter. A small meteorite travelling at thousands of miles per hour will penetrate an AC component on a spacecraft and may cause stress fractures. If the stress fracture is not repaired it will almost certainly enlarge and cause further problems.

An astronaut on a spacewalk may be able to perform a repair but it would be a great deal safer if the component could fix itself. A development of composite materials based on biological repair mechanisms may have achieved that aim. With repairs to animal tissue, the blood hardens over damaged tissue to enable new skin to form underneath. Replicating that concept, a small percentage of the strands in the self healing composite material is hollow and contains the uncured resin. The resin carrying strand has to be of a material that will break upon impact and so glass was chosen. With animal tissue the blood reacts with air to harden but in space or undersea there is no air to effect curing. Instead a matrix of alternate hollow fibres contain a resin and a hardener and the combining of both liquids allows the repair solution to fill the cracks and harden. A consideration for use in space has been the performance of the liquids at extremely low temperatures. Other repair methods have been investigated such as microscopic capsules containing the resin and hardener and a matting that will repair itself when heated. It may be some time, however, until a self repairing compound is a reality.

Presentation techniques for your exhibition display stand

We are all simple creatures at heart. Show us something shiny, pretty, sparkling or attractive and we will be interested. Take packaging for example. Children’s cereals are packaged in brightly coloured boxes often including a cartoon character having fun. The children will ask for this cereal and often the parents will buy it even though it may not be the tastiest or healthiest. It’s the same with clothing. The goods in clothing catalogues are usually modelled by attractive people but the actual clothing may not look quite as alluring when worn by the customer. It’s also the same for events and exhibitions. When preparing an event, the organiser needs to make sure that the product or service is presented in an attractive and interesting way. PC games stands at exhibitions, for example, should have a high tech feel with LCD screens, areas to try the games and an attractive young girl or two in a Lara Croft or superhero outfit. Sexist? Possibly. Realist? You bet! The girl or girls on the display stand may also seem like a role model for young female customers and the older male game players won’t be too upset either.
Products implying natural or healthy ingredients would benefit from having a some trees or plant displays on the exhibition stand. For exhibitions and company presentations, plant display hire is an ideal way to brighten up a dull venue. The addition of plants and flowers on their own won't be able to disguise a really unattractive venue but they can draw visitors eyes away from the bad bits and towards the good parts. Water features can also be included where necessary.
For business presentations, a subtle plant display placed either side and at the front of the stage or presentation area will add another dimension and may keep the audience interested for that little bit longer!
Flowers and plant containers can be colour co-ordinated with the company colour or logo although this is often not really necessary as the flowers and plants will be appreciated if they are presented in an attractive way.