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Martha’s techniques to help your plants beat the heat
Just as your garden is going full tilt, along comes the toughest weeks of the year with blistering heat. As temperatures reach the 90s, many plants wilt or cease to flower, and your containers may require daily watering. For humans, too, the hot spells are hard to bear. But you don’t have to gaze out hopelessly from the air-conditioned indoors, longing for May. By heeding these helpful techniques, you and your garden can both keep your cool.
A plant’s need for irrigation changes constantly with the weather, the season, and the stage of the plant’s growth, but the following guidelines can be applied universally. Mornings are the best times to water – when water pressure is high, evaporation is low, and the soil can absorb the water before the sun heats up the ground.
A rain gauge shows how much natural precipitation has fallen, so you can tell at a glance if you’re in for a day of watering or relaxation. Place the rain gauge in an open area with no trees or structures overhead. Be sure to empty the gauge after each rainfall. It will help you determine how to adjust your watering accordingly.
Make sure to moisten the whole area of soil penetrated by the plants’ roots. Saturate containers until you see water beginning to seep out of the drainage holes in their bases. Water garden beds until you have moistened the soil to a depth of at least six inches. Measure the depth to which the moisture has penetrated by digging into the soil with a small trowel and checking for wetness with your fingers.
The rate at which you irrigate is also important, because if poured on too quickly, water only runs off across the soil surface, which won’t benefit the plantings at all. To cope with finer silt and denser clay soils, install an inexpensive electronic timer on your outdoor faucet. Set it to operate a sprinkler for twenty minutes at a time and allow a couple of hours for absorption between each watering interval.
If your garden is on a hillside, you’ll find that soaker hoses or a drip irrigation system with pressure-compensating emitters are your best watering tools.
Plants lose moisture through their leaves. When temperatures climb, they can suffer from a serious water deficit. Sidestep this problem by knowing when and how much to give different plant types.
Type of Plant | Time of Day | How Much |
---|---|---|
Annuals |
Early Morning |
1-2 inches per week |
Perennials |
Early Morning |
1-2 inches per week |
Vegetables |
Early Morning |
1 inch every 5-7 days |
Trees / Shrubs |
Evening / Night |
1-3 inches each week |
Continue to weed out any unwanted plants. Weeds rob your plants of needed nutrients and water. Remember that it is easier to keep up than to catch up.
Mulching, or top-dressing your soil, is an effective way to preserve precious moisture during dry spells. It not only makes your garden beds look neat and tidy – it improves water retention and helps suppress thirsty weeds. It also keeps the soil cooler during heat waves.
Now is an excellent time to apply 2-3 inches of fresh natural mulch in your beds, taking care to leave some room around the base of your plants to prevent rotting. Water thoroughly after applying mulch. Miracle-Gro All-Natural Mulch is an excellent choice.