To reduce water consumption:
- Avoid watering in the middle of the day during hot weather — up to 50% of the water will evaporate before it soaks into the ground. Whenever possible, water your plants before 9 a.m. or, if this is not possible, in the late afternoon — i.e. between 5 and 6 p.m. if this does not go against regulations in place in your municipality.
- Water less often but in greater quantities. In-depth watering encourages the development of long roots that will help the plants survive the next drought.
- Generally speaking, check the soil’s drought level to determine the right time. Before watering a border, use a trowel to dig a hole about 10-cm deep. If the bottom of the hole feels hot and dry, it is time to water; if the soil is cool and damp, it already has enough water. In the case of a border of recently planted annuals or plants, water when the soil is dry, at a depth of about 5 cm. The lawn can be watered if the soil is dry at the roots — i.e. at 8 cm.
- When using a sprinkler system, slowly water with small droplets, particularly on argillous or very inclined grounds, which cannot absorb a lot of water at a time. If you notice runoff, stop watering for a while and start again later.
Choosing the right watering system
There are three major watering system categories: sprinkling, manual watering and micro-irrigation. Each group has benefits and inconveniences.
Sprinkling
This method uses a static, rotating, oscillating or pulsating sprinkler that projects water over big distances. There are many inconveniences to sprinkling:
- Up to 70% water loss through evaporation
- Promotes the development of fungal diseases when done at night
- Badly adapted to small gardens (certain plants can get too much water)
- Promotes the settling of surface soil.
This watering method should be limited to large surfaces (lawn implantation, springtime seeding in a large garden). Adjust the water flow and position of the sprinklers so as to prevent runoffs.
Manual watering
This method is very time consuming, but it is accessible and economical. It also enables targeted watering where needed. It is important to water the soil — and not the plants — directly. Avoid the formation of puddles and runoffs. To reduce the workload, spread out watering over several days, watering one section of the garden at a time.
Micro-irrigation
For optimal use of water — which is released into the soil where it is needed — this is one of the best watering methods. Water is released slowly, without settling the soil. Water losses through evaporation are limited and plants’ foliage does not get wet, which reduces the risk of fungal diseases.
Made of porous rubber, soaker tubes are very useful in vegetable gardens. They do have a tendency to keep their rounded shape, however. It is therefore difficult to use them in a straight line. Despite this, it is fairly easy to place them around vegetable patches that have just been planted. The water pressure needs to be lowered when they are plugged to a faucet, as the porous tubes are low pressure. This feature makes it possible to plug them directly or indirectly to the exit of a water collection barrel.
Drip irrigation systems come in two main formats. Some models consist of a double-walled tube that releases water through small holes at regular intervals. There are also systems with secondary tubes that have small drippers placed at the base of each plant. Contrary to soaker tubes, drip irrigation systems can easily be placed in straight lines, but they are more expensive and not as easy to operate as soaker tubes.
Underground automatic systems consist of pop-up sprinklers and a network of tubes permanently installed in the ground. These systems are very sophisticated and expensive, and they make abusive use of water when not managed by specialists.