Watering plants in the ground

Pouring some water around the base of a plant is easy! However, making sure that it gets the right amount, not too much or too little is better.

The right amount

The amount of water to give a plant depends on several factors, its natural requirements (depending on whether it is planted in dry or humid soil), the quantity of rainwater that it receives, the texture of the soil (sand or clay). These factors vary and it is difficult to precise exact amounts: the same plant could survive without any water or it could need at least 200 litres a year !

Firstly, find out the needs of the plants that you have planted or those that you are considering. Favour those that are drought resistant if your soil is sandy or you are in an area that is dry. In damp areas such as in a valley or next to a watercourse, do not bother planting specimens that require very little water, as we will discover, they will soon be ill.

Some guidelines

When you see a plant’s leaves wilting it is imperative to give it some water. With experience, you will notice this shortage of water a little earlier: the leaf will loose its shine and will be more dull than normal during the few hours before it starts to wilt. Plants that are wilting on a regular basis will need more often and regular watering: increase the amount of water given each time (if the soil is clay) or increase the frequency (if the soil is sandy).

For trees and shrubs, it is harder to notice the lack of water, because its branches do not wilt. A yellowing of its leaves (sometimes from August onwards), a limited irregular growth as well as out of season flowering all indicate a shortage of water. Do not worry; in dry and porous soil give about 50 litres of water a week to a young tree that is growing !

Certain plants have strange ways of showing a chronic thirst. With tomatoes, the leaves will curl up whilst with box it will take on an orange tint.

How to water

When you use a hosepipe, you often have the impression that the plant is quickly flooded. The water quickly runs out and makes a lot of noise, but often only a litre of water has been given to the plant whilst it needs ten times this! Carry out this test: count the number of seconds needed to fill a watering can and then adjust that time to suit the use of a hosepipe when watering the plants. With a watering can it is easier to know how much water is being given, a full can or half a can.

Too much water: the dangers

Good watering means not over watering. Many plants suffer from a waterlogged soil from too much watering. This is often the case with roses, which develop root diseases and then die. Hedges composed of evergreen shrubs such as the Eleagnus will often take on a yellow colour. If the excess water lasts for too long they will loose their leaves and die. Often the beginner will think that they are thirsty and water them even more… thus increasing the problem! You need to reduce watering and check the soil before watering again; if it is damp to the touch then wait longer.

Silver leaved plants especially the more sober of them can turn yellow if they get too much water. They are often less downy and grey than normal. Their stems are more upward pointing and look weakened. Their soft tissues will be attacked by greenfly and other insects, which try to profit from their weakened state: in this case do not even bother to get the watering can out !

M. Jean-Michel GROULT
Pépinières PLANFOR
1950 Route de Cère
Tel : (020).7660.0178