I got an assortment of young Japanese maples and some of them have died to what I think might be Pseudomonas and Phytophthora. Their trunks slowly turned black and leaves wilted pretty fast. Several times mushrooms were growing in the pots. The pictures of the ones with no leaves sadly did not make it, and the one with leaves is that last one to show signs of deformation, and I am trying to save it if it is possible. Are the curled deformed leaves from a fungus? Someone recommended a product called Phyton 27, but I have some questions and concerns about using it as my garden is in the same area when my dog hangs out and not sure if its safe to use fungicide due to runoff etc. This stuff seems pretty toxic. Does the one with leaves look like it has Pseudomonas and/or Phytophthora? I'd like to avoid using the fungicide if I can. I let them dry out quite a bit before watering again. I could put this maple in a place where my dog does not go to give it a treatment. What would be the best way to use Phyton27 for this maple? Soak/spray? Should I use it on all my maples? and whats the best temperature to do a treatment for these? Any tips or suggestions on how to save this maple is greatly appreciated, thank you.
Yea big part of my confusion. Its in the 90s here in california today so im confused about watering after getting all this fungus and now fungus gnats. Should I only water like once a week? This heat wave has made it hard to judge it all.
Wet and compacted so 'oxygen starvation'. Let it dry out and prick the surface. Overwateriing is a no no especially in the Spring. It causes Maples stress then the bugs attack a weakened tree. We have all succumbed to this in the early days of Maple growing. They can recover. Osoyoung has hit the nail on the head.!!!!
Gotcha! I just fluffed up the top soil and poked it around. Looking much better. Do you think a treatment of phyton27 is overkill?
^^ I would never, ever apply that kind of chemical treatment to a weak or recovering tree. Never. (etc.) Yeah, I think that's the crux of the biscuit.
OK. Phyton 27 is just copper sulfate. It is safe to use around dogs or humans, the only issue is, if you eventually use a ton of it, it could poison your water table. It's the same thing vintners spray on grape vines. No question, everything is too wet, you probably should have repotted earlier to provide sharper draining substrate. So, that's the most important thing, and that's what is hurting the young grafts. Copper is a bactericide and a fungicide. Bacteria is what causes the black spots. If you see blackening, copper is your friend. Make sure you spray with a very fine pulverization, and you can repeat application every 1-2 weeks. If phytophthora is a real concern, you can proceed with a drench of Aliette, but personally I can't imagine that would be called for.
Thanks for the info. The maples I have have been drying out pretty good now. Should I repot them with some grit to the mix or is it too late for that since they arnt dormant?
Hi Streamgrove, I would not disturb them now, they have been under some stress as it is. Leave it till the Autumn then repot in a good quality gritty potting mix. But only do this if you see the roots coming out of the bottom of the pot. When you do repot do not go for a large size. Go for the next size up only each time. It is a gradual process. Hope that's of help, glad they are now recovering.
Hey you know, I use this expression all the time. Better than carbon14, Alain. ;) Oddly there are those who don't know that the crux of the biscuit is, of course, the apostrophe! Streamgrove, if the maples have put out a good flush of growth prior to June, then that's an excellent time to repot; between the two flushes of growth that JMs have. As Acerholic suggests, given their state this might not be best, but you can evaluate when the time comes. Indeed, keep pot size small, and don't try to "help drainage" with pot shards or anything like that. (It doesn't help, it hurts). I reread your original post, I guess I replied pretty late last night, and didn't see you were concerned about your dog. Copper is perfectly safe to use around dogs and other pets, just don't spray them. It's mostly poisonous in large quantities, otherwise in the quantities we use in our gardens it is even authorized for organic gardening.
So I started using a moisture sensor about 4 inches down to gague the watering. Theres dry, moist, and wet. Been letting them hit dry then giving them a light spray to bounce to the moist stage. How long would they prefer to stay in the dry stage, like 3 days? Good to know about the copper, might save that for next year when they are stronger. The ones that are healthy did give a nice push of growth last month. Thanks all for the help appreciate it.
Hi Streamgrove, brilliant you now have a moisture sensor. What you are now doing is perfect. 2 - 3 days is about right but it does depend on the weather conditions. If it's hot as Los Angeles can get I'm sure, then go totally by the water meter and the look of the leaves. Really glad it's all working for you.
ok awesome! Yea apart from the nasty heat here the air can get really dry not to mention santa anna winds. I heard JMs dont like their leaves getting wet, but if I mist them prior to sunrise would that be good or bad?
Hi Streamgrove, don't wet the leaves in the morning, late in the evening is best for misting. You do not want water on leaves and then a hot sun. If possible a humid atmosphere created by water nearby is good in a hot area. If you only have a few maples in pots then place a bucket of water very close to them. This has worked for me in the past.