Timming Lilac and Azalea
When is the best time to trim lilac and azalea bushes? Can you trim them low, as they are over 7 feet tall? I have two hydrangea bushes that are quite large but have never bloomed. How can I get them to bloom?
Certified GKH Gardening Expert
I would not prune either of the plants back by more than 1/3 in any one year. Cutting back any further than that could harm the plants. These articles should help: https://www.gardeningknowhow.com/ornamental/shrubs/lilac/pruning-lilac-bushes-when-to-trim-lilac-bushes.htm, https://www.gardeningknowhow.com/ornamental/shrubs/azalea/pruning-azaleas.htm As for the hydrangea, you may be lacking phosphorus. If there is a lack of phosphorus in the soil, plants will have little to no blooms. You can either use a phosphorus rich fertilizer or add some bone meal to the soil. These articles may help as well: https://www.gardeningknowhow.com/ornamental/shrubs/hydrangea/hydrangea-not-blooming.htm, https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/phosphorus-plant-growth.htm