Plants | Water and Watering
Although they look fairly solid, green plants are about 95 per cent water. They wilt when not watered. Water also provides plants with their own internal transport system, moving nutrients and manufactured carbohydrates and hormones to wherever they are needed, in order for the plant to grow, survive and reproduce.
LEAVE IT TO NATURE
In the wild, plants get by without being watered. Our garden in France hadn’t been cultivated or watered for 12 years, but there were climbing roses, vines, lilacs and bulbs surviving, despite the monster brambles. Even in very dry conditions, these plants, with their well-established root systems, survived a hurricane, several years of drought and the odd patches of sub-zero temperatures. That’s why the Bordeaux area is renowned for its vineyards: the vines have roots which go down 10 metres in the sandy soil, in search of water. As their roots remain undamaged by digging, they can produce grapes, with a bit of help, for 50 years or more. The vines in our garden, however, were not good-looking specimens: raggy and surviving to produce very small grapes, not good enough for a garden.
In gardens we don’t want to grow the plants that appear naturally, ie. those commonly called weeds. We want man-made cultivars and exotic species which have been artificially propagated, pricked out, potted and transplanted. Because the roots have been damaged by interference, cultivated plants develop smaller, shallower root systems. Because they are growing away from their natural environment, they are never as robust as native species, but we still want them to grow strong and look more attractive. Watering is one way of helping them to do better.
However small your garden, there’ll be times when you need a supply of water to keep plants growing and producing flowers or vegetables. Most established plants can survive in the ground with little in the way of artificial watering, either from a watering can or hosepipe. Even if you live in an area where water is plentiful and you don’t suffer regular hosepipe bans as soon as the sun warms up, you don’t really want the expense of additional water bills, if you’re a new homeowner. Saving water is becoming more urgent with the onset of drier summers, so one practical way of cutting the bills and watering as and when the need arises is to use rainwater.
Installing water butts, with lids and taps, is a simple way of collecting water from the roof. If you cut a section of drainpipe with aand insert a rainwater diverter, the diverter sends the water to the butt until the butt is full, then lets it continue down the pipe to the normal outlet. We have a pair of butts connected to each other from a roof downspout situated alongside a greenhouse. These two 100-litre containers have lids which are childproof and keep out most insects as well. The initial outlay has been recouped every year in a saving of water bills, which, in an area with water meters installed many years ago, has to be good news.
Other butts are sited around the garden to avoid carrying watering cans long distances. Even a small roof area, for instance a greenhouse or shed roof, can provide quite a useful amount of water for little effort. Simply attach some guttering to the side of the roof and extend the end of the guttering over a container. We use old dustbins, and kitchen waste bins for smaller quantities. A lid is desirable to prevent algae forming and to keep it smelling okay. The downsides are that you are provided with a great breeding ground for midges and that rainwater tends to be slightly acidic, so is not good for acid-hating plants.
The upside, though, outweighs the disadvantages, in that you won’t be tempted to sneak out in the dark to use that lovely new hose on a reel that cost the earth.
Much more sensible than giving yourself the extra fuss of watering those lush, thirsty exotics is to ‘go with the flow’: to select plants that will thrive in particular conditions without excessive watering. You can tell a lot about plants by looking at their leaves. In hot dry areas where water is short, plants have evolved ways of retaining moisture with waxy skins, furry leaves or silver coloration that reflects light. Desert plants have often given up on leaves altogether in place of tough spines instead. In damp, humid places plants like hostas don’t have to worry about saving water, so they have large, thin leaves. Tropical plants, which make up the majority of houseplants, have glossy leaves with drip tips to drain off excess water.
If, however, you are new to gardening, but don’t have any problem with finances, you could go for a small-scale sprinkler system or drip watering system. This avoids having to carry cans around and can be better for the plants. With a drip feed system you can run both spray and nozzles off the same system. Connect the master unit to a hose from the mains. The master unit reduces the water pressure and contains a removable filter. Run the main supply where it won’t be too visible, e.g. under a hedge or buried in the soil. Connect smaller branch tubes wherever you need to take water to a particular part of the garden. Drip feed heads can be used to water containers and individual plants in a border. If you have gone this far, you might as well go for broke and get a tap computer as well, which will save you the trouble and turn theon and off at programmed times, even when you are away on holiday.
A spray head can be used for more general watering, such as flower beds or rows of vegetables, but beware! Once started, the plants will expect regular treatment, which may not be possible during periods of drought. All the oscillating static, rotating or pulse jet and static sprinklers in the world will be no good then. They sound and look fabulous and can be a lot of fun in hot weather, but we’re talking gardening here!
Seep hoses are designed to be laid along the ground for long-term watering. The tiny perforations deliver water slowly so that it seeps well into the soil. They are especially useful for irrigating rows of fruit or vegetables. Some are made of porous rubber and aren’t very pretty unless you bury them in a shallow trench 10-15 cm (4-6 in) deep.
WAYS OF MAKING THE WATER GO FURTHER
This is a very good way of keeping moisture around the roots of plants. Even drought-tolerant plants will need some help until their roots are established, so water plentifully when planting, then use black plastic, old carpet or newspaper, covered with bark chips, grass cuttings or shingle.
Plant ground cover species thickly to prevent water loss and to keep down the weeds, which will take all the moisture from your beloved seedlings. Keep the weeds at bay by hoeing or hand weeding.
GIVE THIRSTY PLANTS THEIR OWN SUPPLY
Cut off the end of a plastic water bottle and stick it neck downwards into the ground, just above the roots. Fill the bottle with water and let it seep down into the soil.
LINE CONTAINERS WITH PLASTIC
I always line hanging baskets with garden compost bags turned black side out. The plastic is tougher. You can still make it look better from the outside by pushing in a layer of coir or, in our case, moss taken out of the lawn.
These can be added when planting to preserve precious moisture.
In summer, water in the evenings so that plants have all night to ‘drink’ before the sun comes out and dries up moisture. Don’t ever water plants while they are still in strong sunlight as they will shrivel up.
In winter, water in the morning, if at all, so that plants dry out before getting cold. This will make them less prone to mildew.