The 3 biggest watering mistakes in high summer (and how to fix them)
In high summer it's not the amount of water that decides your harvest, but when and how you water. Three mistakes cost you effort, water and plants — and all three are easy to fix.
When the temperatures climb above 25 degrees, many gardeners simply water more — and the leaves still droop in the afternoon. The reason is rarely a lack of water alone, but timing, technique and habit. These are the three mistakes I see most often in my own garden every summer, and all three take just a few minutes to fix.
Mistake 1: Watering a little every day
Strolling over the beds with a can every evening feels caring — but it turns your plants into couch potatoes. If only the top layer of soil stays moist, the roots have no reason to grow deep. They settle just below the surface, exactly where the soil dries out first in the next heatwave.
Do this instead: less often, but thoroughly. Two or three times a week, give enough that the water soaks 15 to 20 centimetres deep. Deep roots can still find moisture during dry spells and make your plants far more resilient over the weeks.
Mistake 2: Watering in the midday heat
You might take it as fact that water droplets act like magnifying glasses and scorch the leaves — but in the garden that’s largely a myth. The real problem at midday is far more mundane: in full sun, much of the water evaporates before it ever reaches the roots.
So water in the early morning. Your plants then have water on hand for the hot day, and the foliage dries off by evening. Watering in the evening works too, but it comes with a catch — more on that in a moment.
Mistake 3: Watering the leaves instead of the roots
Water belongs at the base of the plant, not over the leaves. Wet foliage that doesn’t dry off overnight is the perfect invitation for fungal diseases like powdery mildew or late blight — especially on tomatoes, cucumbers and courgettes. That’s also the catch with evening watering: if the leaves stay damp into the night, the disease risk climbs.
Water slowly and precisely, straight onto the soil. That way every drop reaches the roots and the foliage stays dry. An old watering can without the rose, or a soaker hose, does the job nicely here.
The mulch trick: keeping water in the soil
Even the best watering technique helps little if bare soil hands the water straight back to the air. A mulch layer of grass clippings, straw or shredded prunings — two to five centimetres thick — noticeably slows evaporation and keeps the soil beneath cool and evenly moist.
As a welcome side effect, mulch also suppresses weeds and feeds the soil life as it breaks down. You’ll water less often, and your beds will sail through every heatwave more calmly.
Raised beds and pots dry out faster
A word of warning for everyone with a raised bed, balcony box or container: raised and limited volumes of soil heat up from all sides and dry out much faster than a bed in the ground. On hot days you may need to water here both morning and evening.
The finger test tells you when it’s time: push your finger two centimetres into the soil. If it feels dry down there, it’s time to water — if it feels moist, wait a little longer.
Keeping the overview
The most common reason for forgetting to water — or overdoing it — is simply losing track. In Rootivo, the Care tab shows you the weather forecast for your location and reminds you of upcoming watering tasks — and in the garden journal you note when you last watered. Over the summer you’ll develop a real feel for what your beds actually need, instead of reaching for the can on a hunch.