Seattle gardening and landscape maintenance begins with proper watering. When trying to determine the frequency and duration of watering periods, always consider the soil conditions, the weather conditions and the plant itself. Healthy plant roots need oxygen as well as water. In clay soils, water can drain very slowly and deprive the plant of the oxygen its roots need. During the summer, the heat and lack of rain can dry out your plants. Windy conditions can also dry out plants, thereby requiring more water than expected. New plants require substantially more water than established plants.
It is best to think of watering in two ways. You can either sprinkle or flood (soak). Different plants like different watering techniques. The best time to water is early morning. This helps to prevent disease by allowing plants to dry completely before the cooler evening temperatures arrive.
Established lawns (2 years old or older) need 1 of water per week. This is normally accomplished in our region naturally from November 15th through March 15th. Lawn roots are relatively shallow but you want to promote deep rooting. Lawns also dry out quickly, so it is best for an established lawn to be sprinkled 3 times a week. Set your irrigation clocks to make sure your lawn is receiving 1 of water per week.
Established trees (2 years after installation) require water monitoring. When established trees need water they prefer a complete soaking. If the soil is not damp at a 6 depth, your tree needs watering. Water until the soil is wet to that 6 depth. During hot weather, soaking the root ball once every week is usually sufficient.
Established shrub beds need .5 of water per week. This is normally accomplished in our region naturally from November 15th through March 15th. Maintaining a 2 layer of mulch helps to keep the water from evaporating too quickly and thereby reduces water usage. Sprinkling is generally fine for most plants. Set your clocks to make sure your beds are receiving .5 of water per week.