Sonoma County Garden Doctors tackle water sprouts, root flares, pests and more
Mario asks: What is the difference between suckers and water sprouts on trees? I was told it is important to remove them on my mature plum tree.
Water sprouts are the vertical and vigorous upright branches that will grow quickly throughout the canopy of the tree. When there is an abundance of water sprouts they will overcome the other limbs and branches thus prevent light from penetrating the overly thick canopy and generally will weaken the tree.
Suckers are those numerous new twigs/branches that appear at the base of the tree or shrub. Ones around the base of the main trunk are referred to as crown suckers. Those upright ones growing farther out from the trunk and the underground root system are also suckers. All will weaken the tree by using up available nutrients. Some trees and shrubs are more susceptible to forming suckers. Ornamental purple plums and crabapples fall into this category and should be cut back to their base as soon as they appear. Water sprouts throughout the canopy will continue to form so repeated removal is important to keep them in check.
Roses will form suckers off of vigorous rootstocks. Suddenly to the untrained eye a new tall spindly cane will seemingly put on several feet of growth and develop blooms of an entirely different color. Eventually the suckers will take over and kill the original grafted rose. The vigorous rootstock is called “Dr. Huey” with blooms of a red burgundy color. Roses propagated from cuttings will not form suckers. Rose suckers should be removed from beneath the soil line by pulling or cutting them back. They may continue to form new suckers so be diligent in your pruning tasks.
Olivia asks: How does one identify the root flare when planting “containerized” and bare root shrubs?
The root flare is identified as the bulge at the base of the tree or shrub that is above the spreading root system. By pulling the soil away from base of the main trunk or stem of the container plants the bulge is visible. Do not plant a tree or shrub lower than the root flare. If one plants a tree or shrub below the root flare rot can potentially set in.
Mike asks: How do I bring an overgrown shrub back to a more desirable shape and size? Over the years, my Abelia “Edward Goucher” is no longer as attractive as it once was. My late parents gave it to me as a Christmas gift for our new landscape.
The least drastic way to rejuvenate your Abelia is to remove 1/3 of the old stems/branches each year. Also, remove all dead branches to open up the shrub to more light and air.
This does not mean shearing as in hedging with loppers, but taking into consideration its original natural structure that is loosely open and cascading. The process may also require some minor pinching or tipping of branches during the growing season. Be patient, Abelia can be rejuvenated easily.
Louie asks: Will deer eat ferns? We have moved to a new home that has plenty of shade and also a plethora of visiting deer. I thought an addition of ferns would be a great textural balance.