How to water your plants

How to water your plants

Watering the garden can take a lot of time during the summer months, especially if there is a prolonged dry spell. If you are new to gardening, it is easy to think the simplest solution is to unravel the hose each evening and shower the whole garden using a hose-end sprinkler. But there are far more effective and less wasteful ways of keeping your garden plants well watered, while reducing the amount of labour it takes. To start with, concentrate your efforts only on those plants that really need it. For example, container plants, such as pots and hanging baskets, are entirely dependent on the water you can supply so make these a top priority when watering, especially if they are growing in a conservatory or greenhouse.

It is also worth concentrating on watering the plants in your garden that will benefit most.These include...

  • New plants that have yet to establish a decent-sized root system, and therefore cannot draw upon water reserves found deeper in the soil.
  • Shallow-rooted plants, such as bedding and young vegetables that rely on drawing moisture from the top layer of soil.
  • Vegetables that produce pods, such as peas, beans, or fruits such as tomatoes, melons and courgettes. These will all produce much better yields if they are watered as the crops are swelling.
  • Other fruit crops will also produce bigger crops if watered while the fruit is swelling, although this is less critical with established tree fruits.
  • Leafy vegetables, such as lettuce and spinach, will put on more lush growth if kept well watered.

Choosing the right equipment and employing tricks of the trade used by professional gardeners to target the application of water also helps. Use as much moisture-retentive organic matter as possible and then mulch like mad after planting. It will save hours of work.

Watering tips

To water effectively, it is essential to apply the water in the right place. This means watering only the plants that need it and not wastefully sprinkling it over the whole garden. It is also important to thoroughly soak the soil periodically rather than watering little and more often. Indeed, watering little and often can actually make matters worse because you will moisten just the surface of the soil, encouraging the formation of shallow roots. This will make the plants more susceptible to drought later on. The best time to water is in the evening to minimise the amount of water lost through evaporation. Watering at this time will also eliminate any possibility of delicate plants getting scorched.

Individual plants

Keep the soil moist around the roots of new larger plants, such as trees and shrubs, by burying a length of plastic pipe at planting time into the soil at an angle so that the bottom of the pipe is aimed at the root area and the top of the pipe is just above soil level. Fill the pipe with gravel so that you can water the root area directly via the pipe. Another technique is to ridge up the soil about 30cm away from the main stem all the way round the plant to create a ‘moat’ over the rooting zone. Each time you water, the ridge prevents the water running off so that it to soaks into the soil where it is needed most.

Rows of plants

A similar trick can be employed for rows of plants, such as a new hedge or a line of cane fruit, this time ridging the soil along the whole row. An old piece of guttering with holes drilled at regular intervals buried rim-deep into the soil alongside the row also works well. Simply fill the guttering each time you water.

Containers

Before planting, it is worth lining porous containers, such as terracotta, with polythene (avoiding the drainage holes) to help prevent water loss through the sides of the container via evaporation. This is also true for open wire-mesh hanging baskets that are very prone to drying out. Use fewer large containers rather than lots of small ones because larger containers hold a lot more compost and so require watering less often. For example, a 35cm diameter basket holds about twice as much compost as a 30cm one.

Add water-retaining granules to growing medium to increase its ability to retain water for longer periods of time. This should help to reduce the demand of frequent watering during dry spells. The granules increase in size when wet so water them before adding to compost to ensure your pots don't overflow!

If you have a collection of small containers, group them together to make watering easier or try plunging them rim-deep into troughs of compost or larger tubs to help reduce the need for watering. Also choose drought-tolerant plants for containers to be placed in a sunny position, such as on the patio. After planting, mulching the surface of the compost with decorative gravel or stones also helps.

Useful tricks

Dried out compost. Compost in containers and hanging baskets that has been allowed to dry out completely can be difficult to re-wet, causing all the water poured onto it to run off before it’s had a chance to soak in. You can overcome this by putting a drop of washing-up liquid into the watering can before you water. The detergent breaks the surface tension of the water which prevents it soak in.

Alternatively, place a few ice-blocks on the surface of the compost and they will wet the compost surface as they melt. Once the surface has been wet, you will be able to water in the normal way.

Watering equipment

Choosing the right watering equipment can drastically cut down on the time and effort you have to put into keeping your plants watered. It’s a good idea to have watering cans dotted all over the garden, an automated system for hanging baskets, and if you have a section of garden you can use as a standing ground for container-grown plants that are waiting to be planted, a retractable hose reel would come in handy.

Hand watering

Most gardeners water at least some plants by hand. A watering can may be all you need if you have just a handful of containers. Consider choosing one with a long spout to increase your reach when watering containers at the back of a collection or in the greenhouse, for example. Similarly, a hose lance that can be fitted to the end of your garden hose will make watering containers in awkward places easier. Choose a lance with a trigger to control the flow of water so that you can reduce waste and save time having to go back and forth to the outside tap to regulate the water supply.

Capillary matting

If you have a lot of containers in a greenhouse or conservatory, capillary matting can be a good option. This is simply a water-absorbent material on which container plants are placed allowing them to draw water as and when they need it via capillary action. You need to keep the matting moist at all times so regular watering is still necessary, although this is a lot quicker than watering individual pots. However, you can completely automate this system by draping one end of the matting into a reservoir of water that is topped up directly from the mains using a ball-cock mechanism.

Automatic watering

You can also automate watering containers outside. By installing a network of micro-tubing with adjustable drip nozzles fitted to the ends, you can give each container exactly the right amount of water each time you turn on the outside tap. This system can be used to water hanging baskets and growing bags too. By adding a crafty water timer to the tap you can even make the system completely automatic.

To automate the watering of ornamental borders and the kitchen garden, install a soaker hose instead of nozzles at the end of the tubing. Water gradually seeps from the hose down its entire length – ideal for watering rows of vegetables or bedding plants.