Gardeners' World presenter Monty Don has issued a critical warning about watering plants during the ongoing UK heatwave, emphasizing that incorrect timing could prove fatal for your greenery. As the nation experiences record-breaking May temperatures, the gardening expert shared his essential advice for keeping plants healthy, particularly those in containers.
When to Water: Morning or Evening
Don explained that the best time to water plants is early in the morning before the sun heats up. If that's not possible, he advises waiting until the evening when temperatures are cooler. Watering during the middle of the day can cause droplets on leaves to magnify the sun's rays, leading to scorching and potential damage.
"The rule of watering is always the same: soak, don't sprinkle," Don said. He recommends watering directly at the roots of the soil or compost until water runs out of the bottom of the container. This ensures roots can reach deep moisture and stay hydrated throughout the day.
Container Plants Need Daily Care
Plants in containers require more frequent watering, especially during heatwaves. Don advises watering them every day when temperatures are high. Despite the increased watering, he notes that there is no need to feed plants more than normal, as they will grow strong and healthy even in extreme heat.
UK Heatwave Breaks Records
The UK is experiencing its hottest May on record, with temperatures reaching 34.8°C at Kew Gardens in London. The Met Office reported that 97 of its sites hit or exceeded 30°C on Monday, breaking the previous May record of 32.8°C set in 1922 and 1944. Tuesday is expected to see highs of 35°C in southern England and Wales, possibly reaching 36°C.
Thunderstorms may develop in the afternoon, which could influence temperatures. The Met Office warns that some areas may not drop below 20°C overnight, following the UK's warmest May night on record at Kenley Airfield, Surrey, where temperatures stayed above 19.4°C.
Heatwave Thresholds and Climate Change
To officially qualify as a heatwave, temperatures must meet or exceed a specific threshold for three consecutive days. The highest threshold in the UK at this time of year is 28°C, applicable to London and areas north towards Cambridgeshire. Eight parts of England had already met heatwave conditions by Sunday night, with many more expected to follow.
Met Office senior forecaster Greg Dewhurst noted that climate change is fueling the rapid development of heatwaves. "In the past, heatwaves built over days, but now they develop so quickly," he said. A study found that breaking the May record is now three times more likely due to climate change, turning a once-in-a-hundred-year event into a one-in-33 occurrence.
Gardeners Share Tips
Gardeners' World followers have also shared their own advice on social media. One recommended watering at the base of plants to avoid scorching leaves, while another suggested creating a "plant paddling pool" using plastic sheets before going on holiday to keep containers hydrated.
As temperatures begin to ease from mid-week, conditions will remain largely dry with sunny spells. However, eastern areas may see a drop of around 10°C due to a brisk easterly wind.
