Prune now to shape out-of-control shrubs
Before continuing out discussion about pruning, I think I should stress what NOT to be pruning at this time.
If you trim anything that flowers in spring before the plant puts on new growth, you are cutting off flowers. These plants include forsythia, lilacs, snowballs (viburnums), azaleas, rhododendrons, red buds and deciduous magnolias.
These plants should be pruned while they are in flower or immediately thereafter.
Ideally you should try to trim before they start pushing any new growth. Cutting a spring bouquet is some of the best trimming you can do!
I prefer to prune flowering fruit trees this way, though sometimes it’s easier when they are out of leaf. If you do prune them now, you’ll still get a few flowers anyway.
Now you’ll say, “Dick, what are you talking about? You just spent the last two columns talking about pruning fruit trees and they bloom in spring on old wood!”
Well, yeah, but the point of cutting back fruit trees is to reduce the amount of flowers so that the trees don’t produce so much fruit that it is crowded and misshapen, hanging on the ends of branches that can’t support it, or deprived of sunlight so it doesn’t ripen properly.
This is why spindly branches should be trimmed back. They not only will support fruit better, but will put on thicker growth that will produce more fruit next year.
A good test is to put your hand on a branch. If it doesn’t feel like it will support several peaches or apples, cut it back to where it is more sturdy.
This is a great time to shape shrubs that bloom on new wood like roses, butterfly bushes, Aztec plume, bird of paradise and rose of Sharon.
Some of these plants (even roses to a lesser degree) can get huge and woody and then wind up falling apart. Butterfly bushes are especially prone to this.
If you have a shrub that has gotten completely out of control, cut it all the way back to about 18 inches. Remove canes that are close together and remove old, barky canes in favor of new, vigorous ones, and try to leave canes that are evenly spaced.
You’ll be amazed at how nice and thick the plant comes back, and since it blooms on new wood, you’ll get plenty of flowers.
Actually, I do this to my Aztec plumes and butterfly bushes every year even though most literature says not to, and they still get too big.
If you have snowballs or lilacs that have gotten so big and woody and unruly that you’re tempted to remove them, you can prune them the same way I just described.
But even if you do it when they are flowering, you still won’t get any flowers next year.
All shrubs benefit from thinning and shaping now or after bloom. Remove crossovers, and thin them so they look organized and tidy.
All plants benefit from good air circulation. Really, it is better to take off too much than to leave a plant thick and broomy.
In the case of rhododendrons and tree peonies, it is important to always cut just out from a bud or the whole branch may die back. So use extra care with these.
I’ve been told my last column (Jan. 24) was hard to understand. If you have any questions about it, do write and I’ll try to clarify — sorry!
NEXT TIME: roses.