Today, I pruned the lilac bush. With spring-flowering shrubs, it is best to prune them when they have finished flowering. They will begin to prepare next year’s flowers soon after this year’s are done. You don’t want to remove any flower buds into which they’ve put energy.
This is what the lilac looked like on May 11th when it was blooming.
When I prune the lilac, I do two things. I remove any stems that extend too far into adjacent plants. I also remove some of the oldest stems to open up the plant so that light can penetrate the center and help new stems grow. I don’t try to “shape” the lilac — its natural, fountain shape is what a lilac should look like. I remove the stems down as close to the ground as I can rather than cutting off part of a stem or branch. This is the result.
There is quite a bit less shrub than there was earlier. I didn’t prune it last year, so I had a lot to do this time. Here is the pile of branches, about 95% from the lilac, waiting to be picked up by the township and turned into mulch.
I used two tools to prune the lilac. For branches up to about 3/4 inch (18 mm) diameter, I used the large lopping pruners. Both the lopping pruners and the small pruners in this photo are of the “bypass” type, i.e. the blade works with a scissoring action. This type of pruner slices the wood and is less likely to crush or otherwise damage the part of the branch or stem that will remain on the plant.
For larger stems, I used a Japanese hand saw. This saw is fairly small and has no back, so it can fit into the tight spaces between lilac stems. It cuts on the pull stroke, which makes it easier to use in my opinion. The teeth are hardened which helps it cut fast. It works well on branches up to three or four inches (7 to 10 cm) diameter.