The Casual Gardener: Water your garden with care
If you must water your plants, make sure you do it judiciously...
EVEN over the wettest summer Ireland has to offer it’s unlikely the amount of rainfall will offset the moisture lost from the garden through evaporation. This means that in some cases the gardener may have to supplement nature’s water supply.
Water, quite literally, is a plant’s lifeblood. Water from the soil enters the plant through the roots by osmosis, from where it is transported through the stems. Nutrients drawn up from the earth and food manufactured in the leaves by photosynthesis are transported around the plant in water before eventually it is lost from the leaves in a process called transpiration. Without water, the plant dies.
However, even though water is free and its supply unlimited to domestic users in Northern Ireland, it still makes sense to conserve it. That day when this vital resource may come with a quarterly charge may be closer than you think – especially if Alliance’s electoral growth continues.
There are many ways to ensure your plants have adequate water. The sustainable gardener strives to have a moisture retentive soil made up of loam, sand and organic matter in the right proportions.
Mulching will conserve moisture in the ground. It is best carried out in spring when most herbaceous perennials are still dormant, enabling easy access to your beds and borders. Mulching with leaf-mould, compost or seaweed after winter also reduces evaporation by trapping the previous months’ rainfall under the protective organic barrier.
However, with exception of greenhouse crops, hanging baskets and containers, it really shouldn’t necessary to supplement rainfall by using a domestic water supply. If you find yourself having to water established outdoor plants regularly, then you’re either growing the wrong kind of plants or there’s something seriously amiss with your earth.
Recently planted trees and shrubs are likely to be stressed under drought conditions as they have no extensive root network to rely on, while newly sown veg may also need a soaking if conditions are dry. These are exceptions, however.
Harvesting your own water in a butt – or several – will reduce the need to use mains water. A butt fed by gutters on or close to a greenhouse should provide enough water over the summer to raise a healthy crop of tomatoes and more.
If you insist on using a watering can, hose or irrigation system, a good technique will save you time, help your plants and reduce your carbon footprint.
Ideally, you want to do your watering early in the morning or very late in the day, to avoid loss to evaporation. It’s also important to ensure your water regime is regular and not sporadic. Fruit, especially tomatoes, are susceptible to splitting if they don’t get regular moisture.
The texture of your earth has a bearing too. Lighter, sandy soils require watering more frequently than heavy soils, but less water can be applied. Conversely, heavier, clay-based soils need less frequent watering but more water each time.
The most important thing to remember is that it’s the roots that need the water not the parts of the plant above ground. Give the area around the base of plant a good soaking, ensuring the moisture goes deep. Be careful not to drench as this may result in run off, which as well as wasting water, washes soil away. Also, avoid waterlogging, as this makes it difficult for the roots to breathe and robs the cells of oxygen.
Keep the water away from the plant’s foliage, as the dampness makes the leaves more susceptible to mould and other diseases.