Any ideas what the cause of the white on the leaves in the first pic is? Also, i've noticed more leaves turning brown as per the second photo. Any advice please?
Good morning Mani. This maybe powdery mildew. The leaves turning brown and curling is often a sign. This is a fungal disease that can be treated. First of all the leaves that have it will fall, so clear them away and destroy. Next there are treatments that you can use. Fungus fighter plus. I use it, but others do not. There are home made formulas that include baking soda, vegetable oil and dish soap. It is up to you what you use. To ensure no further attacks, make sure plants are not crowded, give them plenty of light and do not over fertilize. Hope that's of some help
Thank you, that's very helpful - is it contagious to other plants? Have you heard of the brand Provanto? They sell a fungus fighter plus product.
Copper pulverization works great for powdery mildew (botrytis). Every wine maker in France (and now England, thanks to climate change) uses it! Even authorized in organic farming in limited quantity. Note that you can't "cure" gray mold you can only destroy it on surfaces. Where it has grown the leaves are likely to die or look spotty anyway. best, _E
@Mani, yes it is unfortunately, that is why you should destroy all the leaves that drop. Also if you have any leaves that look as though they have it already, I would remove and destroy. Fungus fighter will not make these leaves return to vitality, it doesn't work like that. The spray is a preventer, not a cure for leaves etc already infected. I have heard of Provanto, but I use Bayer, as I have had the best results with this one. I have tried the home made organic methods, but for me it didn't work. Not saying it wouldn't for you.
Hi Do you think that this one is suffering from powdery mildew also? It's only on a couple of leaves but should the whole tree be sprayed including the trunk? Thanks!
@Mani definatly I'm afraid Mani. Spray the whole tree later in the evening and not in full sun light. If it were me I would remove those two leaves and destroy. It is only two and they are likely to curl and drop soon anyway. Powdery mildew can spread very quickly, so the sooner you start treatment the better.
Thanks - I've got the treatment now so I will spray them tonight. These two trees were about a metre apart in a shaded area, I guess too shaded! When pulling off the leaves do I take their stems too?
@Mani, yes, they should come off as you remove anyway, unless you are using secateurs. Ahh they were fairly close together, there is the evidence. Start the spraying tonight, do not worry if more leaves show signs and drop, it is easy to miss early signs of infected areas. Do update the thread on how it goes.
@Acerholic, for Bayer, do you use a solution as directed on the packaging or do you make it less strong?
@Mani, I use it as directed on the bottle. Btw watch the weather this evening as I believe rain is forecast over night. No point in applying if the rain washes it straight off.
Ugh! Does this white covering on the bark look like powdery mildew also? I wonder if i shouldnt just treat all of my trees?
@Mani, yes it looks like it to me. Spray the whole tree. I actually spray 'all' my young trees in the Spring as a preventative measure. My larger makes have to fend for themselves, but I do ensure an open structure in the February pruning to allow good light and air flow.
@Mani, that depends on the overall health of the tree, age etc. If it is a small two year graft and it is completely defoliated by the mildew then almost definatly. Larger trees can and do survive this. 'Do not worry' your trees will be fine and as long as you start the treatment now, they may even recover some leaves on second flush. They will appear a bit unsightly this season, but that will be all. I'm certain you will be posting lovely looking trees without powdery mildew in a few weeks time.
Well, first treatment has been completed. Now it's a waiting game! I used 2.5litres = 10ml of Bayer Fungus Fighter Concentrate (purely for my records!). @Acerholic after how many days do you usually apply a second treatment? The instructions are rather vague saying 7 to 14 days!
@Mani, well done for getting it done, I'm afraid it's a waiting and monitoring game. Sometimes a second treatment is not required, but it is easy to miss parts even though you think you have covered everywhere. You should see a marked improvement in 7 days IMO. Do remember though that leaves already infected will continue to curl, brown and drop. Do not worry about this. Do update the thread with photos of the improvements.
@Acerholic will do! Fyi anyone in the UK, Homebase are offering a 7L pressurised insecticide sprayer for £7.95, 40% off the normal price. Made this job A LOT more efficient!