‘Best time to water plants’ during a heatwave or risk killing them completely

During the summer months, plants and vegetables get very thirsty, and depending on the location of the plant, it might need watering twice a day. 

But when is the best time to hydrate your garden? Presenter and QVC gardening expert Mark Lane explained how watering plants “at the wrong time” is one of the “worst mistakes” a gardener can make during hot weather. 

He said “the best time” to water plants “is early in the morning when the outdoor temperature is cooler, between 5:00 and 9:00 am”. 

As for why he suggests the early hours of the morning, Mark said it will “result in less water lost to evaporation” as the day heats up. 

“Early morning is preferable to late evening watering” because the plant can “dry off quickly which helps protect against the development of fungal diseases”, he added. 

READ MORE: Common watering mistake that could ‘hinder tomato plant’s growth’

Whereas “watering at night can result in water pooling on the soil’s surface, around the roots and on the foliage which can lead to fungal growth, rot, insects and even the death of a plant”. 

Whilst the time of day is important, so is the volume of water, and despite plants getting thirsty in the heat, less is definitely more during heatwaves. 

Henry Bartlam, founder of Dig said to avoid giving “plants a daily light sprinkling of water”.

Instead, it’s “better to give them a good soak every couple of days (especially in warmer weather) than a quick splash every day”. 

“There is no precise science to this, but if the soil looks nice and damp, and doesn’t dry out quickly, you’ve probably done a good job,” she added, but warned: “Be careful not to overwater and saturate the soil though – not only could this eventually damage the plants, but also wastes valuable water.”

One way to reduce the amount of water that evaporates from the soil during hot weather is by “spreading a layer of mulch”, and this will keep it cooler. 

Sean Lade, director of Easy Garden Irrigation suggested adding “roughly a two-inch layer” to “ensure your plants will be happy throughout the hot weather”. 

Gardening experts at Power Sheds also offered crucial tips for protecting plants during the hot weather. 

1. Move plants that are in pots or containers into a shaded area as container plants dry out first in a heatwave.  

2. Don’t overwater your lawn, as it can do more damage than good and leave it scorched. Instead, to keep lawns looking thick and green, water once a week and mow once a week.