Key takeaways
- Deep-rooted crops like Jerusalem artichokes and sweetcorn cope best once established
- Rosemary, sage, thyme and oregano rarely need watering once settled in
- Autumn-planted garlic and broad beans crop before the summer heat arrives
- New Zealand spinach and chard keep cropping in heat where spinach and lettuce bolt
- Mulch 5-8cm deep on moist soil and water deeply once a week rather than a little daily
The best drought-tolerant vegetables for UK gardens are deep-rooted crops like Jerusalem artichokes, sweetcorn and chard, plus Mediterranean herbs that are built for dry summers. Another clever trick is to grow crops that finish before the heat arrives, such as autumn-planted garlic and broad beans.
No vegetable crops well with no water at all. But choose the right crops, mulch the soil and water deeply rather than often, and a dry summer becomes far less stressful. For flowers and shrubs that cope with drought, see our guide to drought-tolerant plants.
What makes a vegetable drought-tolerant?
Crops cope with dry weather in one of three ways.
- Deep roots reach moisture well below the surface. Jerusalem artichokes, chard, sweetcorn and globe artichokes do this once established.
- Tough, grey or hairy leaves lose less water. Rosemary, sage and thyme are the classic examples.
- Dodging the summer by growing through winter and spring. Garlic and autumn-sown broad beans are nearly done by midsummer.
The first to suffer are shallow-rooted leafy crops: lettuce, spinach, radish, rocket and pak choi. They bolt in hot, dry weather, so sow them in spring and late summer instead.
The best drought-tolerant vegetables and herbs
Mediterranean herbs
Rosemary, sage, thyme and oregano rarely need watering once established. They come from dry, sunny hillsides and dislike wet soil more than drought. Plant them in sun with good drainage, adding grit to heavy soil.
Rosemary loves a sunny raised bed with sharp drainage, and it’s happy to go weeks without a drink once settled.
Jerusalem artichokes
These are about as tough as veg gets. Jerusalem artichokes grow up to 3m tall and crop with little watering once established. Plant tubers 10-15cm deep and 30-45cm apart from February to April. Lift the knobbly tubers from October through winter as you need them.
They spread from any piece left in the ground, so give them a corner of their own. Our Jerusalem artichoke guide has more on keeping them in check.
Jerusalem artichokes make a tall, tough screen on the plot, with sunny flowers in late summer and tubers to dig all winter.
Swiss chard and perpetual spinach
Chard and its cousin perpetual spinach have deeper roots than true spinach. They keep cropping through summer where spinach would bolt. Sow from April to July, 30cm apart. Water in dry spells for the best leaves, but they won’t sulk as quickly as salads. Rainbow-stemmed types look good too.
New Zealand spinach
New Zealand spinach isn’t a true spinach. It has thick, fleshy, triangular leaves and loves heat. It doesn’t bolt in hot weather like ordinary spinach. It’s frost-tender, so soak the seed overnight and sow indoors in April. Plant out after the last frost, about 60cm apart. Pick the soft shoot tips from June until the first frost.
Sweetcorn
Sweetcorn has deep roots and copes with dry spells better than most summer crops. Plant in blocks rather than rows to help pollination. Water well after planting, and again when the tassels appear and the cobs swell. The sweetcorn growing guide covers timing.
Globe artichokes and asparagus
These perennial crops grow deep roots once established and rarely need watering after their first year. Globe artichokes suit a sunny, well-drained spot. Asparagus takes a few years to start cropping but can last 20 years. Both are covered in our guide to perennial vegetables.
Tomatoes and chillies in the ground
Tomatoes aren’t truly drought-tolerant, but in the ground with mulch they need far less water than in pots or grow bags. Water deeply and regularly rather than little and often. Chillies prefer their compost to dry a little between drinks.
A thick mulch around outdoor tomatoes keeps the roots cool and the soil moist between deep weekly waterings.
Which crops dodge the dry weather?
Some crops avoid drought by doing most of their growing in the cool, damp months.
Autumn-planted garlic is ready to lift in early summer, before the driest weeks really bite.
Garlic planted in October or November roots through winter. Bulbs swell in spring and are lifted in early to mid-summer, usually before the driest weeks. Plant cloves 2-3cm below the surface, 15cm apart. Softnecks such as Solent Wight store well. Hardnecks such as Lautrec Wight need a cold winter. See when to plant garlic for timings.
Broad beans sown in October or November, such as Aquadulce Claudia, crop in late spring before the summer heat. Spring-sown beans are more likely to struggle in a dry June.
Winter purslane (miner’s lettuce) is sown in late summer and early autumn. It crops through the cooler months when dry soil is rarely a problem.
Thirsty crops to water first in a drought
When water is short, prioritise these.
- Runner beans need water when flowering, or the flowers drop without setting pods.
- Courgettes and squash have big leaves and need a deep soak every few days in hot weather.
- Potatoes need water as tubers start to form, around flowering time.
- Lettuce, spinach and celery bolt or go bitter if dry. Grow them in spring and autumn instead.
- Anything in pots, grow bags or newly planted needs checking daily in hot spells.
Runner beans drop their flowers if they go dry, so give them a good soak when they’re in bloom.
How to water and mulch for a dry summer
Mulch while the soil is moist, usually in April or May. Spread 5-8cm of garden compost, straw, leaf mould or well-rotted manure around crops. It slows evaporation, keeps roots cool and smothers weeds. Our guide to what mulch is and how to use it explains the options.
A seep hose under a straw mulch puts water right at the roots and stops it drying off the surface.
Water deeply, less often. A thorough soak once a week reaches deep roots and encourages them downwards. Daily sprinkles only wet the surface and keep roots shallow.
Water at the base, early in the day. Aim a can or hose at the soil, not the leaves. Early morning loses least to evaporation. A seep hose under mulch is a handy way to do it.
Collect rainwater. A water butt on every downpipe keeps your crops going when hosepipe bans arrive. The hot weather watering guide covers heatwave priorities in more detail.
Dry-summer vegetable calendar
| Month | What to do |
|---|---|
| January | Plan crops for dry beds. Order garlic and broad bean seed for autumn |
| February | Plant Jerusalem artichokes. Set up water butts |
| March | Plant Jerusalem artichokes and asparagus crowns. Sow chillies indoors |
| April | Sow chard. Sow New Zealand spinach indoors. Mulch moist beds |
| May | Plant out sweetcorn and tomatoes after the last frost. Water in well |
| June | Plant New Zealand spinach. Mulch summer crops. Water deeply once a week |
| July | Lift garlic when the leaves yellow. Water runner beans when flowering |
| August | Keep weekly deep soaks going. Sow winter purslane |
| September | Sow winter purslane. Harvest sweetcorn and chard |
| October | Plant garlic. Sow autumn broad beans. Start lifting Jerusalem artichokes |
| November | Finish garlic and broad bean planting. Mulch empty beds |
| December | Lift Jerusalem artichokes as needed. Review which crops coped best |
Common mistakes in a dry summer
Watering a little every day. It only wets the surface and keeps roots shallow. Water deeply once a week instead.
Mulching dry soil. Mulch holds in whatever is there. Soak the bed first, then mulch.
Watering at midday. Much of it evaporates before reaching the roots. Water early morning or evening.
Sowing salads in midsummer. Lettuce and spinach bolt in heat. Sow them in spring and late summer.
Using sprinklers on veg beds. Sprinklers wet paths and leaves as much as roots. Aim water at the base of plants.
Frequently asked questions
What vegetables can survive a UK heatwave?
Deep-rooted crops such as Jerusalem artichokes, chard and established globe artichokes cope best. Mediterranean herbs like rosemary, sage and thyme also shrug off heat once settled. Garlic and autumn-sown broad beans avoid the problem by cropping before high summer.
How often should I water a vegetable bed in dry weather?
Water deeply about once a week rather than a little every day. A thorough soak reaches deeper roots and encourages them to grow down. Seedlings, new transplants, pots and leafy salads need checking more often.
Does mulch really help in a dry summer?
Yes, mulch slows evaporation and keeps the soil cooler. Spread 5-8cm of compost, straw or leaf mould in spring while the soil is still moist. Putting mulch on dry soil just keeps it dry.
Which vegetables need the most water?
Leafy salads, courgettes, runner beans, celery and potatoes are among the thirstiest crops. Beans need water most when flowering, and potatoes when tubers form. Grow lettuce and spinach in spring and autumn rather than midsummer.
Can you grow tomatoes without daily watering?
Yes, in the ground with mulch and steady deep watering. Give a good soak two or three times a week in hot weather rather than a splash every day. Keep watering regular, because big swings in moisture cause split fruit and blossom end rot.
Is it best to water in the morning or evening?
Early morning is best, with evening a good second choice. Less water is lost to evaporation than at midday. Aim the water at the soil, not the leaves.
For more water-wise ideas, browse the growing hub or read our guide to water-efficient gardening to make every drop count.
Our team produces practical UK gardening guidance from source research, contributor records and established horticultural practice. Editorial standards are overseen by Matt W.
