Knowing how much and when to water your plants can be tricky, and unfortunately the anwer isn’t totally black and white. Thoughts of weather, plant preference and soil type need to be on the brain.
The rule of thumb is an inch of water per week, but everyone who has ever been a kid knows rules were made to be broken, or at least bent—sorry, mom. In especially hot weather, plants need to guzzle an extra half-inch of water for every 10 degrees the average temperature is above 60 degrees.
Remember when you were sitting in math class and thinking, “When am I ever going to need this in life? Never, that’s when.” Surprise. To find the average, all you need to do is add the daytime high and nighttime low, and divide the sum of those numbers by two. For example, if the daytime high is 87 degrees and the nighttime low is 73 degrees, the average is 80. At this temperature, your garden would need an extra inch of water for the day.
The soil moisture test is another way to determine if your plants need another round or if they should be cut off. To check if your plants’ roots have enough available water to drink and aren’t thirsty, dig down approximately six inches and check to see how moist the soil is. If the soil is damp, congrats, your plants’ roots aren’t parched. If the soil is dry, grab that watering can or hose and let your flowers belly up to the bar.
When watering, focus on the roots and not the leaves. It is the roots that do all the drinking, after all. You wouldn’t pour a glass of water on your arms if you were thirsty, would you? Any water spent on the foliage is a waste, and can promote the spread of disease.
Watering cans are a great way to deliver water where it’s most important—the roots.
Is there such a thing as too much water? Just like a lack of water will leave your plants high and dry, too much water will have them drowning and gasping for air. If you’re finding small lakes in your garden after even a moderate rainfall, your soil may not be draining properly. To correct this, try mixing in more organic matter or digging a grave channel to reroute the water.
Not surprisingly, there are optimal times in the day to water your plants. The early mornings are the absolute best time to give them a drink because it supplies them with the hydration they need to face the summer heat head on. But we live in a busy world where a morning sip isn’t always possible. In those cases, the very late afternoon is your next best time. Just be sure to allow enough time for the leaves to dry before nightfall to avoid development of fungal diseases.