Watering Your Garden in Hot Weather: What Actually Works
How to water a UK garden in heat and drought, covering timing, deep watering, mulch, lawns, pots, water butts and which plants to prioritise.
In a hot, dry spell, it is easy to spend hours with a hose and still lose plants. The key is not more water, but better-targeted water, applied at the right time and in the right way.
Water the right things first
You cannot water everything, so prioritise.
- Newly planted trees, shrubs and perennials, planted in the last year, whose roots have not yet spread.
- Containers and hanging baskets, which dry out quickly.
- Vegetables and fruit, especially while setting and swelling crops.
- New lawns and turf. See laying turf step by step.
- Plants showing stress, such as wilting in the morning, not just the afternoon.
Established trees, shrubs and lawns are generally tougher than they look. A brown lawn in summer is usually dormant, not dead, and will green up after rain.
When to water
Water early in the morning or in the evening, when less is lost to evaporation. Morning is best for most plants, since foliage dries during the day, reducing disease. Avoid watering in the full midday sun.
How to water
Deeply and less often
A good soak every few days encourages deep roots, while little sprinkles keep roots near the surface and make plants more vulnerable. As a guide, a couple of buckets or watering cans per large shrub, or enough to wet the soil to around 15 to 20cm, is better than a quick splash daily.
At the base
Direct water at the soil around the plant rather than over the leaves. A hose laid at the base, a watering can with a long spout or a leaky hose all work. Water around a ring beyond the stem to reach feeding roots.
Let it soak
Pour slowly so the water sinks in rather than running off. On baked soil, make a shallow dish around the plant, or water in stages.
Cut down on water loss
- Mulch beds with a 5 to 7cm layer of compost, bark or leaf mould after a good watering. This reduces evaporation and keeps roots cool.
- Pull weeds, which compete for moisture.
- Raise the mower height and mow less in dry spells; see how often to mow your lawn.
- Move pots into shade in the hottest weeks.
- Group containers so they shade each other, and use saucers carefully to retain moisture.
Use water wisely
- Collect rainwater in water butts connected to downpipes. A couple of butts can supply a surprising amount over a dry spell.
- Reuse grey water such as washing-up water, in small quantities, on ornamental plants, avoiding soapy water with strong chemicals.
- Follow any local restrictions if a hosepipe ban is in force. Watering cans and butts are usually allowed.
- Consider drip irrigation or a timer for veg beds and pots, which can save water if set sensibly.
Plants that cope with dry conditions
If summers are drying your garden out year after year, choose tougher plants: lavender, sedum, ornamental grasses, rosemary, cistus, verbena, and many Mediterranean herbs. Group plants by water needs so thirsty ones are together and easy to look after.
Raised beds and containers
These dry out faster than ground soil. See raised beds for vegetables for tips on soil and mulch. Large pots with a water reservoir, or a layer of gravel on the surface, help.
Holiday cover
If you are going away in summer, ask a neighbour or hire help for watering and basic care. Give clear instructions about which plants matter most. On Compito you can search by postcode, compare ID-verified local providers and send a request for watering visits, then message them to agree timings. See how it works.
Worked example: a week of hot weather
A heatwave is forecast for seven days. A household with a small garden, two large pots and a vegetable bed makes a plan. They fill a water butt from the downpipe, mulch the vegetable bed with compost, move the pots into a shaded corner and water new shrubs deeply once at the start of the week rather than daily. Tomatoes and courgettes get a thorough soak every two or three days in the early morning. The lawn is left to go brown. By the end of the week the plants look stressed at midday but recover each evening, and the water used is far lower than if they had sprinkled everything daily.
What to water and how often
| Plant type | Approach |
|---|---|
| New trees and shrubs | Deep soak weekly in dry spells |
| Containers and baskets | Daily in heat, morning |
| Veg and fruit | Deep soak every two to three days |
| Established borders | Leave unless wilting persists |
| Lawn | Leave dormant, unless new |
Common mistakes
- Sprinkling lightly each evening, which encourages shallow roots.
- Watering leaves and not the soil.
- Mulching dry soil without watering first.
- Forgetting pots under eaves, which do not get rain.
- Ignoring drainage and leaving pots sitting in water.
Special cases
- Flats and balconies. Containers dry quickly, and wind adds to it. Use saucers carefully and move pots to shade.
- Rentals. Check restrictions on hosepipes and tell the landlord if irrigation is needed.
- Away on holiday. Group pots, water thoroughly beforehand and arrange help.
- Hosepipe bans. Watering cans and butts usually remain an option.
After the heat
When rain returns, give the garden a few days to settle. Check for scorched plants, cut back damaged growth and add fresh mulch. Plants that did well in the heat are good candidates to repeat.
Frequently asked questions
Is it bad to water in the evening?
Not really, though it can encourage slugs and fungal problems in damp climates. In a hot, dry spell, evening watering is fine, and a good option when mornings are busy.
Should I water the lawn?
Usually not, unless it is new or you want to keep it green. Established lawns recover from dormancy when the rain returns.
How can I tell if a plant needs water?
Check the soil a few centimetres down. If it is dry, water. Wilting leaves that recover in the cool of the evening may just be heat stress rather than dryness.