How to Save Your Houseplants From Heat and Harsh Sun

In summer, water more often but always check the soil with a finger first, filter the midday sun coming through the glass, feed every 2-4 weeks and raise the humidity if the air is dry. The rest is vigilance: your plants live the opposite of winter, with more light, more warmth and most of them growing at full speed. That means they drink more, dry out faster and suffer if you neglect them for a few days.

1. Water more often (but always check)

With the heat the soil dries out much faster, so almost every plant needs more water than the rest of the year. Even so, don't water out of habit: overwatering is still the number one cause of death.

How to tell it really needs water

• Check with a finger: push 1-2 inches into the soil. If it's dry, water; if it's still damp, wait.
• Water thoroughly: soak until water runs out of the drainage and empty the saucer ten minutes later.

Summer rule: during a heat wave, check small pots every one or two days — they dry out in no time.

What time of day to water

Early morning or evening, never at high noon with the pot in the sun: cold water on a baking root ball gives the roots a thermal shock, and much of it evaporates before it reaches the bottom. If the pot has been sitting in the sun for hours, let it cool before you wet it.

2. Shield them from harsh direct sun

More light isn't always better. Midday sun through glass acts like a magnifying glass and scorches leaves, especially tropical plants used to jungle shade.

How to filter the strongest hours

• Move thin-leaved or tropical plants away from south-facing windows.
• Use a sheer curtain to filter the strongest hours.
• If you move plants out to the balcony, acclimate them slowly: start in shade and increase light gradually to avoid burns.

Signs of too much sun

Pale or dry brown patches on the side of the leaf facing the sun are burns. Move the plant somewhere more sheltered, and don't cut off the whole leaf if it still has green areas. How to tell them apart from other blemishes, and what to do next, is in our guide to plant sunburn.

3. Raise humidity when it gets hot

Hot, dry air dries out leaf tips. Tropicals (calatheas, ferns, marantas) feel it the most.

Ways to build a humid microclimate

• Group plants together to create a humid microclimate.
• Set pots on a tray of pebbles and water, with the base not touching the water.
• A humidifier is the most reliable fix if your air is very dry.

The percentage each plant type actually wants is in our guide to humidity for indoor plants.

Why misting in full sun backfires

Avoid misting at midday: droplets can act as a lens and mark the leaves, and the effect on ambient humidity lasts only minutes. If you do mist, do it first thing, once the sun is filtered.

4. Use the growing season to feed

Summer is peak growing season, so it's when feeding pays off most.

• Feed every 2-4 weeks with a diluted, balanced fertilizer.
• Less is more: a weak, frequent dose beats one strong hit.
• To really understand amounts and timing, review our guide to fertilizing plants.

5. Watch out for holidays

Summer is travel season, and a week with no water at 95 °F can finish off a plant. Before you leave, group them in the coolest room, away from direct sun, and set up a watering system. You'll find simple tricks in our watering while away guide.

Common summer problems

Symptom	Likely cause
Leaves wilting in the afternoon but recovering at night	Brief heat, water is fine
Wilting that doesn't recover	Lack of water or damaged roots
Dry, pale patches	Sunburn
Brown tips	Dry air from the heat
Weak, stretched growth	Too much shade despite summer

What NOT to do in summer

• Don't repot during a heat wave: the plant is already stressed; wait for milder days or, better still, for next spring as our seasonal houseplant care calendar suggests.
• Don't leave standing water in the saucer: in the heat roots rot even faster.
• Don't water a pot that's baking in the sun: let it cool down first.

Summer plant care is mostly about not neglecting them: enough water, shade during the strongest hours, and a little humidity. Has your plant gone downhill in the heat and you're not sure if it's thirst, sun or something else? Try it in our AI diagnosis and find out.