Day

July 20, 2019

Watering Tips During Periods of High Heat

With the summer heat firing up, it is essential that we spend the extra time watering the plants new to the garden and those that have been in the landscape over the years. 

When should you water?
The best time to water your garden is from 6 am to 10 am. Watering early in the morning gives your plants plenty of time to drink up the water and any moisture on the leaves to dry off before nightfall. If that isn’t possible, the next best time is from 4 pm to 7 pm.
Try to avoid watering at night, as cool and wet conditions could encourage fungi and bacteria to develop and slugs, snails, earwigs, and other pests to appear.

Can you rely on sprinklers and irrigation systems to get the job done?
Unfortunately, NO, just like people, plants need thorough hydration during times of excess heat. New plantings that haven’t yet established their roots and flowering containers are certainly more vulnerable during excessively high temperatures.

Newly planted trees, shrub, annuals, and perennials in the ground benefit from a long, deep soaking up to three times a week and may need more during stressful heatwaves. Watering by hand with a garden hose at the base of the plant allows the water to penetrate slowly and fully into the soil. A good rule of thumb is to water slowly, to a depth of at least 6 inches for approximately 20 minutes. We know that may seem like a long time; however, the roots of your plants will be encouraged to grow deeper and stronger, and the extra moisture will protect them from the hot soil surface.

Container plants are more susceptible to drying out than their in-ground counterparts. During those hot summer days, these potted plants need special attention and may require watering every day or even twice a day. It may also be helpful to move them to a partially shaded area in the afternoon.

Is mulching helpful?
Absolutely! Organic mulch like shredded bark or wood chips conserves moisture, smothers weeds, regulates soil temperature to keep plant roots cool in summer, and adds small amounts of nutrients to the soil through decomposition. It also prevents soil (and whatever fungi and bacteria are lingering in the ground) from splashing up on the leaves while watering, which reduces the spread of disease.

Water your plants, but hold back on fertilizing, why?
Very high soil temperatures (above 85°F) can cause plants to go semi-dormant, so they use very few nutrients while they’re in survival mode and aren’t prepared to make use of them. Withhold the fertilizers (or apply a weaker diluted solution) until the weather cools off a bit and your plants have a chance to recover.