When can I prune?
Our top question this time of year is when can I prune? If you have shrubby perennials that have browned or are dead on top, you can cut them to the ground now.These will be the woodier plants like Hamelia patens, Esperanza, Flame Acanthus and others. You can prune asters to their rosettes now.
For others that have foliage that’s brown or even some green: Those above-ground plant parts, which may look completely lifeless, have sugars and other plant nutrients in them that may take a while to make their way down into the roots. They also serve as a small amount of protection to the soil around the roots of the plant, and those are two reasons why it’s really best to leaves those unsightly “sticks” alone until we are into late winter. Another reason is that pruning stimulates growth. And when a plant is trying to “go to sleep” for the winter, you need to go ahead and let it do that.
But then, when the plant is truly dormant, many plants do need to be pruned, to clear out all the dead growth and make way for the growth.
To renew evergreen Salvia greggiis, this is the time to cut them back several inches to encourage compact, fuller growth. If left unpruned, they’ll continue to grow, but will get leggy and just look unkempt. You should remove back to the source (the main trunk or the ground)any woody stems that are obviously dead.
How to prune trees may be a little more obvious. Whether they’re leafless or evergreen, they are dormant, so now is a good time to prune them. Trees susceptible to oak wilt should be pruned by mid-February at the latest.
But one group of plants we should hold off on are evergreen shrubs, at least until we’re closer to the last freeze date. Pruning now will encourage tender new growth that can be damaged by a late winter freeze, or even a frost.
Also, wait until mid-February to prune your roses.
You can go ahead and cut back ornamental grasses now, or you could leave them another month, since they provide habitat for overwintering butterflies and other garden creatures.
Since pruning for most of us takes more than one weekend, work your way through the obviously dormant, woodier plants to the more herbaceous perennials that could be damaged by a hard freeze if new growth emerges.