Watering Deeply is achieved by applying the equivalent of a one-inch rain event over the entire root zone of the planted area. This will soak the soil far deeper than one-inch deep as the water travels down through the soil, providing moisture to the roots further down. Depending on landscape conditions and soil type, providing one inch of irrigation can be anticipated to wet the soil to approximately 1’ deep or more.
After watering deeply
After deeply watering, it is equally important that the soil is allowed to dry for a significant period of time before watering again. This is especially important in warm weather when watering too frequently in the upper inches of the soil can cause plant disease issues.
Many California native plants did not evolve in areas that naturally receive rainfall in the warm part of the year, so they are sensitive to soil diseases that thrive in hot and wet soil. By only watering infrequently, according to our recommended irrigation schedules, plants have the potential to thrive, receiving enough water to keep them looking as good as possible through the hot part of the year without wetting the warm upper inches of the soil too often and causing issues for plant health. By watering deeply and infrequently you will be maintaining proportionately more of the moisture deeper in the soil where temperatures stay much cooler and the roots can healthily access water.
Start with our recommendations, then adjust as necessary
All our recommendations should always be used as a baseline, adjusting to your site as necessary. Based on your conditions, usually related to soil type, some sites may benefit from up to 1.5” of water applied during deep watering. These gardens are often ones with clay soil and may also benefit from less frequent watering.
To learn how to achieve deep watering in your landscape weather you have sprinklers, drip irrigation, or hand water, visit our How to water waterwise or California native plants page.