Even without water restrictions in place, it makes sense to use water sparingly in your garden. And if you know how to water your trees correctly, you can encourage growth and save water at the same time. Here are some guidelines for watering your trees the right way:
Get water to the roots
Ideally, one should install a computerised drip irrigation system to ensure that the water reaches the roots of the tree without going to waste.
If this isn’t possible you can always improvise with a soaker hose or a leaky pipe covered with a thick layer of mulch and coiled around the base of the tree. The mulch will prevent the water from evaporating too quickly and keep the soil moist. This gives the roots more time to absorb as much moisture as possible.
Take soil conditions into account
How often you need to water your trees will largely depend on the type of soil you have. Clay tends to retain moisture better than sandy soil which means you may be in danger of over-watering and drowning your trees. Loam is ideal because it has the right balance of water retention and drainage.
Prune trees to reduce transpiration
If you took Biology in high school you might recall that transpiration is the process whereby plants (and trees) absorb moisture through their roots and then emit water vapour through their leaves. Transpiration helps to keep trees cool and deliver the water and minerals required for photosynthesis to the leaves.
By pruning your trees during times of drought, you reduce the foliage and therefore the opportunity for transpiration to take place. This means the tree will retain more moisture without you having to water it more frequently.
Water at the right time of day
If water restrictions are in place you must follow them, but watering your garden in the early morning or late afternoon is common sense. As temperatures are lower, the water will have a chance to soak into the soil before it evaporates. This is especially important for trees that need time to absorb the moisture in the soil through the fine hairs on the ends of the lateral roots.
A word about indigenous trees
Water wise gardeners know that planting indigenous trees will reduce the amount of water you use. However, it’s not enough for a tree to be native to South Africa. The tree should also be native to the zone it’s planted in. That means that trees you find in the tropical parts of South Africa (such as KZN) would not be suitable for dryer climates such as the Karoo.
When trees don’t get enough water their leaves will wilt, discolour and start falling off. You can avoid this by ensuring that you give your trees enough water at the right time. That way you’ll keep your trees happy and healthy, even when water restrictions are in place.