I am wondering when to trim a Daphne shrub. Up to 2-3 years ago, I have always had flowers in the Spring, before the leaves. The shrub is getting quite big and needs a trim. When should I do it, and why has there been no flowers for the last 3 years?
Daphnes are beautiful but can be temperamental shrubs.
They dislike being pruned and may suffer die back after a hard pruning. Therefore, prune only when absolutely necessary, and go gently. While you can remove dead, diseased, damaged, dangerous or crossing branches and even some of the oldest growth at ground level, trim the growing stems lightly. It is true that the best time to prune Daphne is in Spring, right after flowering, taking care not to prune off the flowering buds as this shrub flowers on old wood. You can prune up to mid-July, leaving enough time for the new growth to harden off before winter arrives but you may lose a lot of the flower buds. Do not prune out any more than 1/4 of the shrub this year. You can do the same for the next few consecutive years until you have it back to the size you want in your garden.
Since Daphnes are susceptible to fungal diseases, take care to sanitize your tools before pruning, to minimize the chance of an infection.
As mentioned before, Daphne flowers on old wood, and as such is vulnerable to winter injury and early Spring frosts that can kill off the flowering buds. We have had two very harsh winters and that may explain why your Daphne bush has not flowered.
In the Spring, after flowering, try fertilizing with a balanced fertilizer to encourage bud formation.