The New Zealand Plant Conservation Network

We have a number of Carmichaelia australis plants in our garden that develop short stubby brown "leaves" (as pictured) as growing tips alongside other plants that don't have this at all. It certainly affects flowering performance as no flowers seem to be associated with such patches. Diagnosis? Cure?

_This_ is what they should all look like at this time of year! Shot showing detail of one of several now large specimens we have that are completely free of this brown stunted new growth and look magnificent. And they are a huge magnet for insects of all kinds.

Hi William. This kind of growth is generally caused by some kind of parasite in or on the plant. These 'witches broom' type growths are generally caused by either an invertebrate on the outside of the plant, such as an insect or mite, or by internal bacterial or viral parasites. Any of these can alter the hosts growth form. I'm no expert but in the case of your broom I would suspect a internal viral or bacterial parasite, as some of your plants are affected, while neighbouring ones completely unaffected. As for a cure I'm not sure? You may have to google it. You could try cutting the worst bits out to divert growth into the good bits, if the plants aren't too badly affected?

Thanks for the advice. Yes, may have to try cutting some affected parts out, though in some cases there might not be too much plant left!