The following was written by Gary Matsuoka for Laguna Hills Nursery's March Newsleter. Sign up to receive great tips like this one HERE! Even though it is almost spring the last 2 weeks were more winter-like than the previous 2 months. It's nice to have snow on the mountains and the hills around us are much greener than last year. What is missing is the sound of rushing water in our local streams. Apparently the water table is so low that very little water makes it downstream. 4 more inches of rain will make me feel a lot better about growing and selling plants this coming year.
If we don't get sufficient rain and severe watering restrictions are put in place there are several strategies you can employ. One is to "stump" plants that can recover from severe pruning.
The fewer leaves a plant has, the less water it will use (the less water it can survive with). Some avocado orchards have "stumped" their trees, cutting them down to 4' stumps. Once cut (winter is the best season to prune avocado trees) it takes 2-3 years to grow back to full size and will require less water during that time. (You also loose 1 or 2 years of fruit production.)
You can cut apple and jujube trees to stumps as well as most shrubs. Just make certain that the plants don't grow back to their original size, or be allowed to grow back to their original size, as new foliage can use more water than mature leaves.
Do not "stump" large shade trees. This will cause future structural problems that results in large trees with branches in danger of breaking off and causing damage or injury.
Certain plants do not regrow or suffer life shortening damage after severe pruning. Pine trees, Tea trees, birch trees, maple trees, stone fruit trees, and rhododendrons are among plants that should not be pruned severely. Their growth can be thinned, "laced out" to reduce their foliage.
I have just stumped a large avocado tree in my back yard. If water restrictions are severe I'll stump my apple trees and greatly reduce the size of most of my shrubs.