|Bougainvillea summer time|
Q. While most of our bougainvillea are in large pots which we bring indoors for the winter, this year we planted one in an above ground planter built around the Jacuzzi. What should I do to help it survive the winter without having to dig it up and transplant it again in the spring?
A. Your bougainvillea will have a better chance of surviving the winter planted in the ground than it will planted in a container. However, expect it to be damaged this winter unless you are willing to apply heat to the area where it is planted and cover the plant all the way to the ground.
|Bougainvillea that has frozen back during winter|
If left unprotected, your bougainvillea will freeze to the ground as soon as temperatures drop below freezing. If temperatures dip quickly below freezing and rise above freezing in a short period of time, damage will be light. If temperatures dip below freezing and stay there for a while, the entire top of the plant above ground is likely to freeze and die.
The death of the top of the plant is not necessarily a big problem. The dead parts can be pruned back close to the ground and encouraged to regrow in the spring. My major concern is protecting the base of the bougainvillea, near the soil, so it can regrow.
Some inexpensive insurance is to pile several inches of mulch around the base of the plant just before it freezes. This wood mulch acts as an insulator which protects wood at the base of the plant from dying. Of course if temperatures get unusually cold for long periods, it is possible to lose the entire plant. But in most winters this will not happen if mulch is used.
In mid-March prune out any damaged plant parts back to healthy wood. Fertilize the plant with a high nitrogen fertilizer and water deeply. After it has re-grown significantly, apply a phosphorus fertilizer either to the soil or spray and liquid on to the foliage.