As the United Kingdom continues to experience spells of unusually high temperatures, gardeners face the challenge of maintaining healthy plants amid heatwaves. Jack Stooks, a seasoned horticulturist with over two decades of experience at Highgrove House Gardens in Gloucestershire, offers practical guidance on managing gardens during hot weather.

Stooks emphasizes the unpredictability of British weather, noting that sudden heat spikes can complicate long-term gardening plans. Rather than overhauling garden designs to anticipate heatwaves, he recommends focusing on nurturing existing plants suited to the local environment.

One key piece of advice is to avoid feeding plants during periods of extreme heat. While fertilizing might seem beneficial, it can actually stress plants by encouraging new growth that struggles to cope with heat and limited moisture. Fertilizer can also cause chemical burns—symptoms include scorched leaf edges, leaf drop, and discolored patches on lawns—due to the salt or nitrogen in the treatments drawing moisture away from roots.

Watering practices are crucial during heatwaves. Stooks advises watering early in the morning, ideally between 5 a.m. and 9 a.m., to minimize evaporation. Evening watering is less ideal because damp foliage overnight increases the risk of pests and fungal disease. He suggests watering less frequently but thoroughly and prioritizing young plants, potted specimens, and leafy vegetables, which are more vulnerable to drying out.

Regarding lawn care, Stooks discourages watering lawns to keep them green during heatwaves, describing such efforts as inefficient uses of water and money. Lawns typically enter a dormant phase when dry but will recover after rainfall. If mowing is necessary, setting the mower blade higher helps promote deeper root growth and greater heat resilience. Leaving grass clippings on the lawn provides mulch that retains moisture, and applying a mix of dry coffee grounds and well-rotted manure before rain acts as a slow-release fertilizer.

For gardeners planning holidays during hot spells, Stooks recommends grouping potted plants in the coolest, shadiest area available. He also suggests using plastic trays that hold several pots and can contain water for root absorption over several days, reducing the need for frequent watering.

With heatwaves becoming more frequent, water restrictions such as hosepipe bans are more likely. Stooks encourages gardeners to install water butts to collect and store rainwater. He notes that these containers can be camouflaged creatively within the garden to maintain aesthetics.

Finally, Stooks warns against overwatering, which can weaken plants by reducing the necessity for roots to develop deep moisture-seeking systems. He advises allowing soil to dry sufficiently between watering to help plants build resilience.

Stooks shares these insights as part of his ongoing work in horticulture education and commentary, drawing on his extensive experience and the perspective gained from the variable British climate.