Cold Climate Gardening

Forsythia before pruning beganBack in April, I discussed my upcoming plans to prune my forsythia bush. It wasn’t flowering very much, and my commenters agreed with me that it needed a heavy pruning. Some even suggested cutting the whole thing down to the ground. But I felt a little too nervous to do that.

Remember the forsythia I pruned so that I could force some branches? It doesn’t look so floriferous out in the open, does it? (For comparison, check out the forsythias here.)

When I’m faced with a plant that’s not doing as well as expected, I try to analyze the situation before taking action. In the case of the forsythia, I observed that the flowers were only on the ends of the branches. If it were cold damage, I would expect the flowers below the snowline to bloom, and the ones exposed to the cold higher up on the shrub to be missing. That’s not the case, and besides, this variety of forsythia is supposed to be bud-hardy to 30 below zero Fahrenheit, and it didn’t get that cold this winter.

The standard advice for pruning spring-blooming shrubs is to prune them no later than two weeks after they’re done blooming. This is because most spring-flowering shrubs, at least, all those commonly grown, develop their flower buds on the previous year’s wood. So if you prune them in high summer, or autumn, you are cutting off the wood that has the next spring’s flowers.
However, it is far easier to see the structure of the shrub you are pruning in late winter, when the temperatures have moderated somewhat but the shrub hasn’t leafed out or started blooming yet. And, in the case of forsythia, you can bring the prunings indoors, stick them in a container of water, and, in about a week, have forsythia blooming in the house. These in the photo were cut about a week ago, on one of those nice days just before winter returned.

This is a photo of my Forsythia ‘Meadowlark’ blooming–sparsely, I grant you, but nevertheless blooming–in September. If I hadn’t been checking for signs of the colchicums recently planted in this area, I’m sure I never would have noticed the yellow blossoms, so it is entirely possible this shrub has done this other years without my being aware of it. On the other hand, dinner table consensus was that it had bloomed pretty poorly this spring, so maybe these were flower buds that didn’t “get it” this past spring. Worse, these could be next year’s flowers jumping the gun, in which case there may well …