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When and How to Water
One of the most frequently asked questions we get is “How often should I water this tree/shrub/flower/container?” And the answer is: It depends. Each plant has specific water needs which are affected by its placement in your yard, the type of soil in which it is planted, and by the current weather conditions.
As a general rule, plants in the ground should receive occasional deep watering, and plants in containers will need frequent (usually daily) watering. The size of the plant determines how much water it needs. Trees generally need 10-20 gallons of water a week, per inch of trunk diameter; smaller shrubs may need only 5 gallons a week. If the weather is hot, dry, and windy the plants will need more frequent watering. Established plants need less supplemental watering than newly planted ones.
The average garden bed needs 1 -2 inches of rain (water) a week. That equates to about 60-120 gallons for a 10′ by 10′ bed.
Just because the top inch or so of soil looks or feels dry does not mean it is time to water. Likewise, just because the top inch is damp does not mean the soil down at the root level is moist. Dig down in the soil about 6-8 inches and check the moisture content. If you can make a moist ball with the soil, it does not need water. If the soil is dry, then it’s time to water.
It is just as harmful to over-water as it is to under-water a plant, so it’s always a good idea to check the soil first.
During the heat of the day you may notice some plants (like squash) wilting even though they have recently been watered. They do this as a way to conserve moisture. This does not mean that it needs more water. If the plant is still wilted in the evening or the next morning that is an indicator that it needs to be watered.
Once you get to know your plants and your soil, you can develop a watering plan that ensures everything gets just the right amount of water to thrive. Until then, occasionally checking soil moisture levels, using either a moisture meter or by digging down 6-8 inches, is the way to go.