Q: I have lots of Bougainvillea growing and really love them, however the most common one (purple single flower) has something wrong with it.
The leaves have a bumpy appearance and seams to be shrivelling up. The top most branches are now nude of leaves. I am worried that it will spread to all the other bougainvilleas.
Can you give me some idea what it is and how to treat the problem. Joan – Lightning Ridge
A: Your comment that the leaves on your problem bougainvillea have a ‘bumpy appearance’ has me puzzled.
‘Bumps on leaves’ in some plants are caused by an insect called ‘psylids’, but I have never heard of psylids affecting bougainvilleas.
Check your problem bougainvillea for scale. These are not all that common on bougainvilleas, though it does happen. Let’s eliminate them first. If present, they will appear as irregular bumps along the stems that are bare, and a few may also be present on the leaves. A spray using White Oil or Dimethoate will fix these insects. These two sprays will sort out psylids as well, but make certain that your spray reaches the underside of all leaves, as well as the upper surface. Make a careful check for the presence of other insects. Bougainvilleas are generally free of insect pests, BUT … it does happen.
Have you, perchance, over watered this particular plant? Bougainvilleas like the soil to be on the ‘drier’ side, and dislike too much water. That ‘could’ be a problem to consider if leaves are dropping.
On the other hand … insufficient watering too causes leaves to drop, AND could be the reason for leaves shriveling up. It could be that the soil in the environs of this particular plant is a bit different to that where your other bougainvilleas are growing in your garden. Localised variations in soil structure within a garden are very common.
Another aspect to consider is ‘irregular’ watering. Many plants suffer from this problem, as do my own bougainvilleas at home unfortunately, and this causes plants to drop their leaves and for some to shrivel up.
Have you fertilised your bougainvilleas recently? If yes … maybe this particular plant was given a bit too much? That could explain the leaf drop and some of them shriveling up.
WHAT DO WE DO NOW? Once the weather warms up, say mid-September, I suggest that you prune away all the dead bits on the plant, give it some general purpose fertiliser, scratch the fertiliser into the soil, give it a really good soaking, and then leave it for three weeks with no water at all.
After that, one more watering and then treat them the same way that you treat all the other bougainvilleas in your garden – whatever it is that you do.
When pruning, make certain that you go down low enough so that you are cutting into green wood … about two or three inches below where the dead tissue begins.
There could be some form of nutrient deficiency with this particular plant, so follow up your first application of fertiliser with another dose two months later. If this does not work, please write in again, but this time with a picture or two of your problem plant.
