Coping With Drought

Coping with an ever more stretched water supply is becoming more of an issue for British gardeners as the years pass, and that’s without considering the many additional impacts of global warming on confused plants and gardeners alike.

• The summers are becoming longer and hotter; resulting in more stress on plants and a greater need for additional ‘supplementary’ water (this being water on top the normal natural supply that falls from above.)
• The rainfall during the natural recharge period (specifically during autumn and spring) has been reducing over the past few years, thus meaning that aquifers and reservoirs are not refilling.

So it’s a double whammy of plants needing ever more water as the seasons get hotter, coupled with the fact that we seem to have -year on year- ever less water to go around.

You could also make a case for an additional third issue, this being gardeners increased demand on water resources; this might be down to gardeners doing more gardening but then again it might be down to necessity of hotter drier weather; so you could see this as being a more ‘chicken or egg’ scenario – you see when it comes to responding to the environment and global warming gardeners are right at the front line, and if we are going to make the most of the situation gardeners will have to think more about water use on several different levels; its not just about the kind of plants (if any) that you use; its also about how to condition the soil, when you water, how you water and where the water comes from.

Hard Versus Soft Landscaping – Paving or Planting?

Its difficult decision for real gardeners -these being gardeners who love plants as a foil, if not a suitable replacement for expanses of decking and paving. But the ‘hard’ surfaces just mentioned don’t require watering, however they might however require cutting down or digging up, and that’s an green issue that needs considering. Also hard landscaping is expensive!

The key is to consider ways of balancing plantings and hard surfaces; the obvious rule of thumb is to consider your hottest, driest spots for hard surfaces. This suites the needs of the majority of moisture loving plants and sunbathers alike, however not everyone wants to bake in the sun! One way around this is to use structures such as arbours or trelliswork to create semi shade. Such shade can reduce soil drying and shelter plants from excessive drying sun, especially if you are using less sun hardy plants – which brings us on to the next major point to consider.

Plant Selection – Sourcing Drought tolerant Plants And Beyond

This is of key significance and you really will need to be prepared to undertake some research if your going to choose the right plants; then again you can use our plant finder database to cut out most of the leg work when looking for drought tolerant plants. Simply return to the home page and search for drought tolerant plants!

That said its not just about using purely drought tolerant plants: we don’t live the Sahara after all, not yet anyway. Yes most gardens contain a number of microclimates that will allow you to grow a wide variety of plants without ever having to water, which is just as well, as the palette of drought tolerant plants is rather limited and most gardeners want to grow a bit of everything. Its all a question of mapping your garden for hot, dry spots as well as dry shade, moist shade or the really useful in between areas of moist dappled shade and matching the plants you want to grow with the conditions that suite them best.

The problem areas are either end of the scale; dry shade and full sun, but even then there are plenty of plants that can be grown.

Plant Types And Features That Suit Shade

If you are looking for plants for dry shade you need to look for the plants that have the following features. Evergreen plants such a hollies, Box, Skimmia, and Sarcococca tend to cope well with dry shade, having tough foliage that is retained for several years.

Plants with larger waxy foliage also cope well with shade; these include plants such as Viburnum davidii, fatsia and Hedera species.

Most dry shade tolerant plants are limited in their ability to flower, tending instead to put their energy into maintaining healthy foliage and this should be taken into account when designing planting plans for such areas. Don’t think flowers, think foliage!

Plants for full sun have very different features, these include silvery tough foliage as seen on Lavender and Rosemary and Santolina; all of which are tough Mediterranean plants well adapted to surviving long dry summers.

Many succulent leaved plants are also very drought tolerant, which have adapted to reduce moisture loss by minimising the surface area of the leaf. Plants such as Sedum and Sempervivum species are good examples seen in the UK.

Finally many alpine plants are very drought tolerant, largely due to their habit of clinging tightly to the ground and having a dwarfish compact form that can hold moisture.

A Few Pointers Ror Planting Up Hot Or Dry Areas In The Garden

• Most silver leaved plants can tolerate dry sunny conditions: Senecio, lavender, Rosemary, are all good examples.
• Plants with thick succulent foliage are also well adapted to moisture stress. Ice plant (Sedums) House leeks and Agave are all examples of hardy drought tolerant succulents.
• Many (but not all) grasses can tolerant drought conditions as can many Bamboos.
• Many trees and hedging plants can tolerate drought and can provide some shading that will reduce the drying effect of the sun. However hedging (and some faster growing trees) can go on to rob soil moisture from less established plants.
• Many ferns and woodland ground cover plants (such as Ivy and Rubus) can cope with dry shade conditions associated with house rain shadows.

When To Water And How To Water

The key to efficient watering is built around quantity and timing. The first rule is simply to avoid watering plants at stupid times. Watering at midday is a definite no no. Not only will you risk scorching plant foliage but you will also loose much of the water through evaporation from warm soil. Also the plant is not physiologically in the best position to take up water. If you have plants wilting in the mid day sun at the very wait a few hours until the sun has set a little.

The best time to water is either early morning prior to sun rise, or better still during the evening (dusk if possible) when the soil is cooler and the plant has all of the night time hours to drink up soil moisture without being stressed.

In terms of method of application, well the most effective way to water is directly to the base of the plant, ideally by an emitter system. The least effective being a ‘water everything’ sprinkler. However emitter systems are expensive so most effective and affordable option (hose pipe ban allowing) prefer a hose with nozzle or lance fitting. This is fine, just be sure to give each plant a good soak at the base of the stem for five to ten seconds and then move on, as too little watering can be worse than no water at all.

Grey Water, Rainwater, Free Water!

I always thought referring to recycled water as grey water was rather insulting; why not green water? Because that’s what it is, water that would otherwise be wasted or lost; water that you might well have paid for, so why not use it again -hosepipe ban or no- for free!

The problem is often collection of such water as it involves some investments in terms of pipes, tanks, time and brainpower! The simplest and cheapest technique is using water buts on down pipes from sheds, housing, glasshouses etc.; this will capture a limited quantity of water which can be increased by using a number of water buts in succession or better still allowing all down pipes to feed into a big tank or maybe a pond which you don’t mind part emptying.

In terms of recycling household water well that’s a little more complicated as you need to separate the water supply. You can reuse bath and shower water as well as some clothes washing water. However you will need to use green detergents, soaps etc. that can break down naturally, otherwise you might end applying toxic products into your soil. Personally I can’t help questioning why we need toxic products for.

Cleaning ourselves and our clothing anyway and recycling grey water gives us an ideal opportunity to remove unhealthy products from our lives; if it’s not good enough for my garden then its not good enough for me!

Again with grey water you will need some sort of tank space for storage as well as piping that will allow you to siphon off usable from usable waste water. The services of a good plumber might well be required, or at the very least a competent landscaper who has experience of working with irrigation systems.

Soil Conditioning And Mulching

Finally we come to the key factor of soil improvement. The most important thing to get your head around is that the soil can and will hold moisture for plants even during the driest of times; quite how much it will do this depends on the soil quality and this can be greatly improved by the gardener.

The hardest soils to work with are sandy poor soils, which will tend to drain freely and hold on to little soil moisture. Heavy clay subsoil’s can be equally problematic; turning to cold slime in winter and to a hard dry brick like material during the summer months. Ironically if you mixed sandy soil and heavy clay 50/50 and added some compost you would probably have something you can really work with!

One way of compromising with problem soils is to approach the soil piece by piece and simply pit planting and improving the soil immediately around the plant being planted. If Im planting an 2 litre plant then I will dig a pit 4 to 5 times the size of the pot and improve the soil with lots of compost and good quality topsoil. The improved mixed soil (which needs to be at least 50% compost and topsoil mixed with original material) can be used to back fill around the planted plant. The plant can then be watered in and given extra protection against the drying sun with a mulch layer if compost of bark over the soil surface. This mulch needs to be at least 10cm deep in order to seal in soil moisture.

Mulching can also help improve the general soil of your garden soil in the long terms; simply applying a layer of well rotted compost over your beds every 3 to 5 years will, over a number of years greatly improve the quality of your soil, meaning that it will provide more nutrients for plant growth as well as locking up more soil moisture over longer periods of time.

To conclude on the question of how best to counter the effects of drought on your garden

The most effective approach will probably involve a mixture of the factors identified above. Quite how far you go depends on how much you love plants, the budget you have to spend and your own dedication and drive! You can start with simply using your brain and going for the most appropriate plant selection (and again Im going to advise you use our plant finder to make the job easier!) followed by soil improvement (something that I would advise as good practise whenever planting) then moving on to the more expensive options of using more hard landscaping and investing in methods of saving your own water and using that on the garden, as opposed to putting ever more pressure on an already stretched water supply.