A guide to watering plants

Information sheet

Different methods are used to water plants, depending on their situation and type. This guide will help you choose which method you should use to water the plants in your garden or classroom.

Soak-up tray

Use this method of watering when you are sowing seeds: use a shallow tray or trough larger than the seed tray or pot. Fill it with water until it is approximately 3cm deep. Stand the seed tray in the larger tray until the compost darkens in colour and is wet to the touch. Do not stand plants or seeds in water for more than 4 hours.

Watering can with rose

This method of watering is used to water seedlings once they have germinated, either in pots or the soil. Using a rose means that water flow is gentle and will not wash the seedlings and compost away.

Watering can without rose

This is probably the most widely used watering method in gardening. It is an easy way to control water flow and is used to water established plants in pots and containers (including hanging baskets). Many gardeners water a seed drill with a can before sowing.

Hose with lance or spray gun

This provides a rain-like effect for watering with a heavier flow than a watering can. More water can be delivered in a shorter time. Using a lance will give extra length to reach hanging baskets or the back of a border.

Hose without a lance or spray gun

Commonly used to fill ponds quickly and water mature plants in containers or those planted in the soil. Kink the hose near the watering end to provide more control over water flow. This method is best used by adults or older children.

Trickle or drip irrigation

Separate pipes originate from a single hose pipe, providing individual pots or plants with water over a period of time. This method is especially useful when growing crops of all one type and size. These pipes are usually set up in their permanent position and can be controlled automatically using a tap and timer.

Seep irrigation

This can be either a flat pipe with holes either side or porous pipe, which allows water to seep into the soil over a period of time. These pipes are usually set up in their permanent position and can be controlled automatically using a tap and timer.

Sprinkler

Unlikely to be used in a school garden, however sprinklers may be used when watering a newly planted area or at times of prolonged drought.

Mist sprayer

House plants are usually tropical plants that need a high humidity. Our indoor spaces can be too dry for most of these types of plants. Use a water spray or mister to spray your plants with water to help keep them hydrated and be happier, healthy plants.

Golden rules for watering

Always water plants well before planting. If the soil is dry, water the planting hole or seed drill before planting or sowing.
The best time of the day to water plants is early morning or in the evening. This reduces the amount of water evaporation and is a more efficient use of this resource (especially if you are using mains water).
Always direct water at the bottom of the plant's stem rather than its leaves. This means the water will go direct to where the plant needs it most.
When watering potted or containerised plants and hanging baskets keep watering until the water flows through the bottom of the pot - this means you have watered enough.

Check if your plants need water by:

Looking at the leaves and stems of your plant. If they are wilted and the compost is dry your plant is desperate for water.
Looking at the colour of the compost or soil. If it's paler in colour than normal the plant may need water.
Touching the compost. Use your finger to check about 2cm beneath the surface. If the compost feels dry your plant will need water.
Checking the weight of your pot. Over time you will get used to its weight when it is wet or dry. This can also be a useful guide when used with the other methods above to decide if your plant needs to be watered.