Gardeners are being urged to be strategic with the way they water plants, especially those in pots or containers on the patio, as a blistering summer heatwave threatens to send temperatures soaring to 34°C. The Met Office has issued an amber extreme heat warning for parts of England and Wales, with humidity making conditions feel intensely uncomfortable and tropical nights keeping temperatures above 20°C.
Amid the stifling conditions and looming threats of hosepipe bans, a separate crisis is unfolding in the nation's gardens. Green-fingered Brits are scrambling to protect their wilting outdoor plants. However, gardening experts say the secret to survival during peak heat hours lies in adding one unexpected ingredient to your watering can: mushrooms.
How mushroom-infused water works
Waine Delaney, a mushroom expert from Monotub, revealed that simple mushroom-infused water can act as a natural defence mechanism for vulnerable vegetation, particularly potted patio plants and container displays. The method is straightforward. Gardeners are advised to chop up a handful of any edible mushrooms, whether fresh or dried, and leave them to steep in a watering can for a full 24 hours.
"Whether they are dry or fresh, mushrooms are natural sponges and are made up of 85 to 90 percent water," Delaney explained. "When placed in the water of a watering can, mushrooms act as a 'hydration pod'."
When poured directly over the roots after sunset, this infused liquid slowly releases moisture into the soil, significantly reducing the evaporation rates that usually plague gardens during intense daytime heat. Furthermore, the process disperses organic matter that stimulates underground fungal networks called mycelium. This natural system enhances the soil's structure, allowing it to retain water far more effectively and facilitating easier fluid uptake for the struggling plants.
Additional benefits of mushroom water
Beyond pure hydration, the mushrooms leach a mild, mineral-rich tonic into the water. Brimming with essential nutrients like potassium, selenium, magnesium, and phosphorus, the mixture replenishes the exact minerals plants crave when stressed by severe heat, all without the risk of root burn associated with chemical fertilizers.
Expert advice on watering techniques
Horticulture experts warn that even if the intense heat breaks into isolated, thundery downpours early next week, gardeners cannot afford to become complacent. Simon, an expert from the popular YouTube gardening channel Walking Talking Gardeners, noted that heavy rain often fails to reach potted soil due to the "canopy effect", where a plant's own dense leaves act like an umbrella, shedding water outward onto the patio.
However, Simon urges caution against mindless overwatering, which can rapidly trigger root rot, leaf discoloration, and dangerous root mold. To strike the perfect balance, he advises resurrecting a traditional technique from the 19th and 20th centuries. By tapping the side of a terracotta or stone pot with a stick, gardeners can read its hydration levels. A dry pot will emit a clear, ringing sound, whereas a thoroughly watered pot will give off a dull, heavy thud.
Heatwave outlook and safety warnings
The innovative gardening tips come at a critical time. Met Office Deputy Chief Forecaster Greg Wolverson warned that the extreme heat will intensify at the start of next week, peaking on Monday and Tuesday. "The warmth will expand and intensify at the start of next week, which, coupled with high temperatures overnight, leads to potential impacts," Wolverson said, noting that humidity will make the air feel close and sticky. There is a strong possibility that the current UK June temperature record of 35.6°C could be beaten.
As the public heads to coastal areas, rivers, and lakes to seek relief from the mid-30s heat, officials are also raising urgent water safety warnings. Samantha Hughes, National Water Safety Partner at the RNLI, reminded those seeking a swim that sea temperatures remain dangerously low. Entering the water can induce sudden cold water shock, and the public is urged to remember the "Float to Live" strategy if they find themselves struggling in the water.
While the heat is expected to regress from the northwest later next week, those in the south and east will endure the stifling conditions the longest, making the mushroom-water trick a vital lifeline for gardens across the region.
