Gardening questions: Pruning

One question that came up at the meeting was whether and when to prune. We particularly wondered if we should be pruning roses now, and when the best time was for lilacs.

After a little research here's what we learned.



Pruning Lilacs
Lilacs should be pruned immediately after they bloom, because the buds (for next year's flowers) blooms on new wood.
We are marginal for lilacs in DC, and the heat makes them prone to mildew which is unsightly but not particularly harmful. In Maine, where they thrive, KL had a hedge that had gotten overcrowded and bloomed very little. A neighbor told her to root prune--ditch along the edge of the hedge with a cutting spade. She did and had a glorious display the next year. It was also a message to divide and donate.




Pruning Roses
Roses should be pruned at various times throughout the year according to the National arboretum:
"Lightly in autumn, removing canes long enough to be whipped by winter winds and those canes with signs of disease. Pruning to remove remaining dead, diseased, and damaged canes is done in early to mid-March just before growth starts. Species and climbing roses are pruned by removing entire canes all the way to the ground to encourage an open, vase-shaped habit. The rest of the roses get pruned to knee height at an outward facing bud. You can do some light pruning to shape the plants during the summer as needed."