Gardeners across the UK are facing a sizzling summer after temperatures soared to record highs in May, but experts say there's no need for plants to suffer. Temperatures in London reached 35.1C on May 26th, sparking fears of scorched foliage – but horticultural experts insist with careful planning and smart techniques, gardens can not only survive but thrive.
Leigh Hunt, Principal Horticultural Adviser at the Royal Horticultural Society (RHS), explains that plants are more resilient later in the summer, but early heatwaves can catch them off guard. He stresses the significant environmental benefits of maintaining green spaces, noting that 'plants provide shade and release moisture; they cool our towns and cities by 2C to 4C.' This highlights the collective impact of individual gardening efforts in mitigating urban heat.
When it comes to watering, timing and method are crucial. British Garden Centres advises watering in the early morning to allow water to soak into cooler soil, or in the late evening if mornings are not feasible. Using a watering can rather than a hose is recommended, as it uses significantly less water for the same effect. Hunt also suggests fitting a sprinkler attachment to hoses to mimic natural rainfall and directing water to the base of plants, under foliage, to ensure it reaches the rootball effectively.
The frequency of watering depends on the garden's specific needs. Hunt clarifies that 'lawns don't need watering' and many established in-ground plants may only require a weekly soak, if at all. However, container plants can dry out rapidly and may need daily attention. Cloud Gardener Jason Williams advises checking soil moisture by inserting two fingers up to the knuckle; if dry, the plant needs a drink. Julian Palphramand, Head of Plants at British Garden Centres, cautions against frequent, shallow watering, which encourages surface roots. Instead, a less frequent, deep soak promotes stronger, deeper root systems.
Experts also encourage the use of rainwater and 'grey water'. Hunt highlights that 'rain comes free from the sky!' and inexpensive rainwater diverter kits can be installed on drainpipes to collect substantial amounts of water, especially after summer downpours. The RHS is actively promoting its 'Mains 2 Rains' initiative to encourage this switch. Additionally, grey water from washing vegetables is considered the best quality for reuse, with bathwater also being a viable option.