Growing condition
Drought stress
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Watch for | Watch for in May | Watch for in June | Watch for in July | Watch for in August | Watch for in September |
What it is
Drought stress is what happens when a plant loses water through its leaves faster than its roots can replace it. Hotter, drier summers are making it a regular problem in British gardens, particularly in the south and east, on free-draining sandy or chalky soils and for anything newly planted or grown in pots.
Symptoms
The first sign is wilting during the heat of the day, which may recover overnight at first. As stress continues, leaves yellow, brown and crisp at the edges, and trees such as birch may shed leaves early or show premature autumn colour. Runner beans drop their flowers, lettuce bolts and turns bitter, and fruit stays small. Effects can be delayed: camellias and rhododendrons that dried out in late summer often drop their flower buds the following spring.
Cause
Low rainfall combined with heat, sun and wind pulls moisture from the soil, and shallow-rooted plants run out first. Rain shadows next to walls, fences and under trees stay dry even after showers. Container compost can dry out in hours. Wilting can also come from root damage, honey fungus or overwatering, so check that the soil really is dry before assuming drought.
Control
Give a thorough soaking at the base, enough to wet the soil to a good depth, rather than frequent light sprinkles that only dampen the surface. Water early in the morning or in the evening. Prioritise new plantings, pots, fruiting crops and leafy vegetables; established shrubs and lawns usually recover. Remove dead growth once rain returns and the plant has reshot.
Prevention
Add organic matter to improve the soil's water-holding capacity, and lay a thick mulch over moist soil in spring. Plant in autumn so roots establish before summer. Collect rainwater in butts, group pots together in light shade, and choose drought-tolerant plants such as lavender, rosemary and sedum for the driest spots.
Plants often affected
Could it be something else?
These problems share some of the same symptoms. Compare them, or run the symptom checker with these signs ticked.
Months to keep an eye out: May, June, July, August and September.
Sources
Identification and life-cycle details were checked against the references below. Text and advice are our own. See our editorial policy.