Tuesday, March 11, 2014
By TOM ATWELL
(Continued from page 1)
Once the deadwood is gone, decide what the plant's pruning budget is: That is, how much can you cut out of the tree or shrub? Cane-growing plants like forsythia and lilacs have a pruning budget of up to 50 percent, meaning you can cut out branches containing half of the plant's foliage without making the plant sick. For trees and tree-like shrubs, the budget is 15 percent.
Start at the bottom of the plant and work up.
"While doing good pruning, you are on your hands and knees with your butt up in the air," Turnbull said.
Remove branches that are so low they are touching the ground. Remove branches that are hitting the house, blocking paths or covering windows. Remove limbs that are rubbing against each other or crossing. Remove the ones that are going in the wrong direction.
But you are not going to be able to do all of that in the first year, especially with trees and tree-like shrubs.
"If you take out everything that is wrong with a tree, you have over-pruned," she said. To get a tree that has been allowed to get too large back into shape could take five years or more.
With mounding shrubs such as rhododendrons, evergreen euonymus, holly and spirea, the best method is "grab and snip," reaching in toward the center of the plant and cutting large branches at a junction. Surrounding leaves will hide the cut. These plants have a pruning budget of about one-third.
For low-growing evergreens such as juniper, you have to lift the upper branches and cut out the bottom branches. The middle of these shrubs have dead and brown needles, and this is the only way you can cut them without the dead showing.
With cane-growing shrubs, you should cut the oldest and largest limbs right down to the ground, allowing the young suckers to rejuvenate the plant. These have the highest pruning budget, and are the best candidates for radical renovation.
You should step back and look at the shrub after every few cuts, figuring out what is the next-worst branch, and keeping in mind the pruning budget for the plant you are working in.
"And if you are paralyzed with indecision, it is time to move on," she said.
Or you could read her book. I can't think of a pruning question it doesn't answer, and she'll give you a few laughs as well.
Tom Atwell has been writing the Maine Gardener column since 2004. He is a freelance writer gardening in Cape Elizabeth and can be contacted at 767-2297 or at: