Watering plants is a must-do garden task to keep them healthy. Newly planted trees and shrubs plus other freshly planted areas need to be kept well watered, but so do annual flowers, perennials, pots, containers and hanging baskets, and the vegetables you’re growing. In other words, there could be plenty in your garden that needs your attention.
Knowing how much to water, how to actually do it, how often, and even what time of day to water are all key to getting the job done effectively. Vital, too, with water supplies under pressure because of climate change, is learning how you can use less mains water and turn to other sources to keep plants growing.
We’ve got the lowdown on watering your outdoor plants, as well as expert tips on keeping your houseplants healthy, too. If you want to make light work of your watering tasks, head to our best garden hose buying guide for our top picks, or check out our best garden sprinkler.
- For more inspiration on what to grow in your garden, head to our plants hub
Using a watering can is – no surprise – a great way to water your garden. It makes it easy to direct the water to the roots of your plants where it’s needed. Wetting the foliage above encourages evaporation and can cause disease problems, too. Water the stem bases but not the surrounding area. This way, you’ll supply maximum water to the roots of the plant you’re caring for and avoid providing weeds with a water supply.
Alternatives to a watering can? You can use a soaker hose. Water can seep through along the length of the hose thanks to its porous layers so that it reaches the roots of the plants you want to water. Or try a drip irrigation system of a scale that suits your plot. You could also consider self-watering pots for your container plants, which allow the roots of the plants to draw water from a reservoir.
If you have a large amount of watering to do, you might want to use a hose. Make sure you have a spray attachment on the end – an aerated version will cut your water use. Make sure you direct water to the base of the stems, as above.
How frequently to water
There aren’t universal watering rules, unfortunately. Plants have different needs, and the weather will affect what you need to do, too. The fact that you’ll have to water more when it’s hot and sunny won’t be news, but windy weather also means plants need more water. Even if it rains, pay attention to how good the rainfall is. If we’re talking light showers, they won’t do much for your plants’ roots.
Container plants need more water than those planted in your garden, so give these extra attention with your watering can. New plants also require more water, and so do larger plants with more leaves. Growing your own veggies? These plants also need frequent watering.
How to be sure you’re getting the watering right? Signs that plants haven’t been watered frequently enough include leaves that droop or curl, and/or reduced growth, or fewer fruits or flowers than you’d expect.
Which times of the year – and day – to water
You’re most likely to need to water the garden from May to September, but don’t count out the possibility from March onwards, and you might have to do it at other times of the year, too, depending on weather conditions.
What time of day to water is, thankfully, a more straightforward issue. Preferably, get your watering done good and early in the morning before the sun comes up. Watering in the evening when temperatures have gone down is a sound alternative.
Which water to use
Cutting down on the use of mains water for the garden is important in an era of climate change and, if you’re on a water meter, it’s a costly way to keep plants growing in any case. In the event that you do use tap water, though, bear in mind that using softened water isn’t advisable, so take the water for your garden straight from the mains rather than providing plants with water that’s gone through your water-softening unit.
The best resource to use for your watering tasks is rainwater, so get yourself a water butt – or more than one. If they have gutters and a downpipe, you could collect water via a shed or other garden building as well as from the house. You could also re-use water from cleaning veggies and salad before cooking.
If there’s a water shortage, you could use grey water: that’s water from the shower, bath, wash basins, and washing machine rinse cycles. Soaps and detergents shouldn’t cause plants problems, but water containing bleach, powerful cleaning products, and from WCs – so-called black water – is always a no-no. Grey water should always be used quickly and not stored as bacteria in it will multiply swiftly.
When water’s short and you resort to grey water, don’t use it for your grow-your-own produce.
What about paddling pool water? If it's a small paddling pool that you've recently filled then that should be fine, but in general we don’t recommend using paddling pool water on the garden because of the cleaners you’ll have used to keep the pool pristine.
Watering indoor plants
When it comes to indoor plants, watering is, of course, a year-round task. As with garden plants, individual houseplants have different requirements, so do adapt your routine to the species.
Generally, over-watering is a danger with indoor plants, so let the compost dry a bit before you water. Water until the compost is moist, letting the water drain into a saucer or the sink.
In winter, most houseplants need less water than they do in the other seasons of the year, so reduce watering.
Let water come up to room temperature before using it on your houseplants. Using rainwater is a good idea and, as with the garden, if it is tap water you’re putting on to plants, avoid softened water.