Smoke Trees (Cotinus spp.) get their name from the wispy growths on the peduncles of the flowers once they have finished blooming. Smoke Trees bloom in the spring, and their true flowers are actually quite unimpressive. It is when these small, green to white star-shaped flowers go to seed that Smoke Trees truly shine. It can be quite disappointing, then, when a Smoke Bush isn’t getting its smokey look.
Common Reasons Why Smoke Tree Isn’t Blooming
The most common reason that will prevent Smoke Trees blooming is pruning. Smoke Trees set their blooms for the next year during the summer and fall, so some old wood should be left on the tree if you would like to see blooms that season. If Smoke Trees are damaged or need to be cut back to the ground for sizing purposes, the best time to do this is in late winter. Severe pruning will remove the bloom sites, however, and the tree will not bloom that year. Another common cause for a lack of blooms in improper lighting. Smoke Trees need full sun in order to thrive, and low light conditions may lead to fewer blooms.
Pruning Smoke Tree To Help It Bloom
Sometimes, extreme cold conditions can damage the bud sites in the winter, preventing the plant from blooming that spring. When it is apparent that your Smoke Tree is not going to bloom, you can try cutting back the damaged branch ends to encourage new growth. Keep in mind that multiple branches may sprout from a pruned branch. Cut damaged branches back lower on the tree to prevent it from becoming top heavy. For severely damaged Smoke Trees, cut the trunks and branches to about 6 to 8 inches from the ground in late winter. This type of rejuvenation pruning will allow the plant to grow anew, but do not expect blooms until the following year.
Fertilizing Smoke Tree To Help It Bloom
Smoke Trees generally do not need much fertilizer, and a lack of nutrients is rarely the cause of a lack of blooms. Fertilizing your Smoke Trees in early spring with an all-purpose slow-release fertilizer can give your Smoke Tree a boost of nutrients but will not likely cause it to bloom. Instead, look for other causes like improperly timed pruning, frost damage, poor soil quality, or improper growing conditions to improve blooming.
Get Smoke Tree To Produce More Blooms
The best way to set your Smoke Tree up for success is to provide it with the right growing conditions. Plant your Smoke Tree in an area where it gets at least 6 hours of direct sunlight. In addition, soil quality is important for Smoke Trees. While these plants develop drought resistance over time, they require regular watering after planting and well-draining soil; soggy or clay-y soil can damage the roots and lead to disease. If pruning is necessary, only remove up to one-third of the branches in early spring to keep flower buds on the remaining branches.
Why Smoke Tree Isn’t Blooming
- Improper pruning
- Not enough light
- Poorly draining soil
- Frost/physical damage
Author Lynn Gusman - Published 7-27-2023