I live in the Central Valley of Ca. On a mature tree, roots extend far in all directions, but it’s sufficient to concentrate on watering the area beneath the branches. Avoid light watering as this promotes shallow root systems that are susceptible to summer heat and drought stress. If you have a drip irrigation system where you are guaranteed that the garden really will get a daily watering, that's fine. How to Water a Redwood Tree. Water trees deeply in the morning. You could try to get around this by giving your plants a little bit of water daily, rather than a good weekly soaking. The roots that absorb the water aren’t deep. greg1140 , … Make a homemade tree watering system with items you already have, like a bucket or garbage bag. For large established trees, water every 3 to 4 weeks in summer — more frequently during record high temperatures. I have 8 Redwood trees that are 40 feet tall and I was curious as to how to water them in the summer? Water established trees and shrubs with overhead sprinklers. Continue watering the tree as above but move the hose further out to encourage root growth. Older trees can survive on a deep watering once a month during a drought, although twice a month would be better. Apply a deep watering over the entire root zone area until the top 6 to 9 inches of soil are moist. Here’s how. They spread out sideways and most are just a foot or so beneath the surface of the soil. That’s where the hose should be placed. Watering Instructions for a Tree Planted Within the Last 2 Years. Your redwood will tell you whether or not you’re watering enough. As the tree grows, roots will spread at least as far as the edge of the tree canopy. Young trees are much more delicate, however, and should be watered at least once per week. Once the drought is over, gradually reduce how often you water your tree until you are watering every other week. Deep watering: If trees are only provided with shallow water every so often, they're probably only getting a fraction of what they need. where it is very hot and my soil has a lot of clay. Deep watering is an effective way to replenish your redwood and conserve resources. Dig down about 24 inches to make sure water reaches that depth.