Age-Old Wisdom meets Modern Tools
How to water plants in extreme heat
If your vegetable gardening is struggling in hot weather, we’ll show you how to help your stressed plants cope with the heat this summer!
Check soil daily by pushing a finger into the soil. Water if it’s dry an inch or two below the surface. A deep soaking every few days is better than a daily sprinkle on the surface.
Water early in the morning while it’s still cool and evaporation is slow.
Work soil into ridges around plants to create bowls. Water into these and the ridges will prevent water running away over the surface, giving it time to soak in near the roots. Or sink old pots or bottles into the soil next to plants and water into these.
If you’re unable to water daily in hot weather a drip irrigation system controlled by a timer is a good idea.
Keep a close eye on container plants. They may need watering more than once a day, especially in windy conditions. Make sure the water is being absorbed fully into the potting soil, rather than just slipping down cracks between the potting soil and the wall of the container. Pour until water runs out of the bottom of the container, and use pot saucers under containers to retain the water for longer.
Mulch after watering with organic material such as compost, leaves or grass clippings to shade the soil and keep the root zone cooler.
Shade the soil with a living mulch by planting densely and/or using plants like squashes that are vigorous or have large leaves.
Adding nutrients also prompts the plant to grow more, putting them under more stress in hot weather, and they’ll need even more water to process the fertilizer too. Stop fertilizing when it gets above 85-90ºF or when plants roll up their leaves, drop their flowers, or stop producing new flowers.
Use shade cloth or other fabric such as old bed sheets pinned onto frames or hoops to provide shade for plants.
Cool-season vegetables, for instance cabbage and lettuce, and fruits such as strawberries, will particularly enjoy shade from hot afternoon sun.
Harvesting fruits or leaves promptly will help save your plant’s energy. Harvest partially-ripened fruits such as tomatoes and finish ripening them in the kitchen to give your plants a break. Plants might slow down in hot weather, but yields should increase again once the weather cools.
Learn more about which plants grow best in the heat.