I saw this fungal infection for the first time at work a few days ago and thought it was worth talking about it, as I learnt something new and it could be of value to you at some point in the future.
Camellia leaf gall is caused by the fungus Exobasidium camelliae. When conditions are wet and humid, it is more likely that it will appear. The symptoms appear in spring here in Sydney, appearing as follows:
- Creamy-coloured galls (swellings) in spring, instead of leaves. Only a few galls appear, the rest of the foliage appears normal, with some new growth also appearing normal.
- Galls are up to 15cm in length although there is no one shape to them-they can be round or oblong, forked or hand-shaped.
- They appear green at first, but turn cream-coloured as large numbers of spores are produced over the underside of the leaf.
- In the process of galls maturing, the lower leaf layers peel off to reveal a wite colour on the underside of the leaves-this white colouration iss the actual spores of the fungus.
- Leaves appear thicker and fleshier than normal spring growth-they can be several times larger than the usual new growth.
- Spores may blow into your garden from elsewhere, so always keep an eye out for anything amiss.
The fungus that causes the problem is host specific, meaning it only infects, in this case, one genus of plants-Camellias. From the information that I have read, it seems that Camellia sasanqua is the species most prone to infection. Other camellias can suffer form this too.
This fungus produces spores that spread by wind or splashing water. The best way to treat this is to remove the leaves when they are found-preferably before the pores are exposed (to reduce the spred for the next gorwing season). All leaves need to be bagged up and disposed of in general waste and not into a compost bin or your green waste bin as the pores could still spread (they will lie dormant until the following spring, if they land in the right place). I could not find any fungicide to treat this problem.
One you have removed all the infected plant parts, be sure to clean your tools, gloves and hands to help prevent spreading the fungus further. Good garden hygiene always helps.
- https://www.rhs.org.uk/disease/camellia-gall, accessed 14/10/2022
- http://hgic.clemson.edu/camellia-leaf-gall, accessed 14/10/22
- All photo sare my own