Disease or Pest? on my Hibiscus

[Rory]

Can you help identify and treat the attached picture. The end of each branch exhibits clumping and stunted growth appearence, the leave naer the end are all tightly curled up.

[helixturnhelix]

Hi Rory,

Cold weather does werid things to hibiscus growth, was this taken during cold weather?  Another thing that pops into mind is aggrobacterium infection, in which bacterium cause the plant to produce lots of auxin and cytokinin, which forms these calluses.  The best thing to do is either wait till spring and cut that part of the plant off or move it inside where its warm and cut it off.  These sorts of callus formation are usually localized and cutting it off solves this problem.  You do not want to prune right now unless you are in a tropical region, Ive made the mistake of pruning when it was too cool and might have lost some plants that way.  Good luck!

[Rory]

I am in Southern Texas near Corpus Christi, we have had some cool weather low of 40, then 75 a few days later.

Perhaps it only the cold, but I do see some very small patches of white like mildew??  near where all this stunted growth is.

I trimmed all of the branch tips back about 8 inches on one large planth. I have several, perhaps 20 large plants with same symptoms.

Would a fungicide like daconil help?

[Charlie]

Rory, I think Chris nailed it with the bacterium diagnosis. Something similar can happen with nutrient imbalances, too, but if you have decent soil and/or use a complete fertilizer that is not very likely. I remember seeing something that looked a lot like this a few years ago after spraying some plants with worm casting tea, which is full of microorganisms. They are supposed to be beneficial but it seems the tea can be too potent for hibiscus when sprayed directly on the plant. Anyway, it was temporary and hopefully your situation will be so, too. Cutting off the tips was a good idea. Let us know what happens in the future!

Charlie