This problem is affecting the leaves of my deciduous and broadleaf evergreen plants. It begins by browning at the leaf tip and progresses thru the entire leaf over a few weeks time. I have lost entire trees due to this but usually the problem defoliates the tree then it regrows new healthy leaves and continues to grow like nothing ever happened. I’ve read that anthracnose can cause defoliation and then regrow new leaves but it doesn’t seem to follow the progression of anthracnose and I’ve not found any photos matching my symptoms. Not positive that it’s a fungal disease. Would a high pH produce these symptoms and would a pH problem affect some species but not others? Overwatering? I have some plants that show no symptoms at all. Is anyone familiar with these symptoms? Any success in dealing with it?
i am having a similar thing on a few of my maples, I think its either weather related, or water related, I have been on top of my fungicides this year.
It looks like sun burn, but there’s likely other factors contributing to this. The leaves pictured are dying from the tips and margins inward…Camilia and magnolia leaves can be much larger, but leaf size will be small, yellow and damaged in direct sun. I struggled with similar issues for years. Last 2 years a lot of issues have been resolved with:
Balance of water and oxygen (thanks Ryan) - this sounds simple, but actually harder than it seems, especially with the variation of container size, shape and difference of requirements across species.
Shade cloth 30-50%, obviously depends on your setting/location.
keeping pots from over heating.
My garden used to have a problem with pest and some other associated issues, but almost all of that was mitigated with the 3 things listed above.
All of these species do well in my hot, back yard with morning sun and shaded light after 11am. It may take a few years to see these vigorous again, less if the roots are healthy with room to grow.
Thanks for your input. The problem I was having occurred last season, ‘22. It was serious and deadly and a frustrating mystery. This season I have not had any instance of that problem recurring. Like most complicated horticultural problems I can’t lay my finger on any one thing I did different this season. I changed up several things: I switched from 30% to 40% shade cloth, I repotted many of the problem plants and used a more open airy mix, and I started using fertilizer pellets and tea bags and removed the fertilizer when the high summer heat hit in Jul-Aug. Another variable outside of my control is the unusually wetter winter and relatively milder Spring-Summer here in the foothills of central California. I strongly suspect that the problem was due to over-fertilizing. I was fertilizing by mixing powdered organic fertilizer into the top of the soil mix monthly during the growing season. I stopped doing that and now only selectively use pellets or tea bags and stop all fertilizing during high heat.
Might not be a single factor… sunburn and chlorosis ( this can come from too high PH)
Chlorosis. Test your water. If your pH is 7.0 or close, then look to the Total Alkalinity. Nutrients cannot be processed without some Total Alkalinity. The EPA Standard for Total Alkalinity is 70 - 150 mg/L.
Low pH results in stunted growth, brown spots on leaves (calcium deficiency), green leaves with red or purple edges, burnt tips (nutrient overload), looking withered and twisted leaves. Low Total Alkalinity results are the same as low pH plus blossom end rot in fruit and leaf chlorosis (the leaf veins remain green, but the rest of the leaf turns yellow).
A quick fix for chlorosis is a foliar spray of micronutrients containing iron. Foliar sprays are only good for existing leaves, so it might take more than one application. Not all fertilizers can be used as a foliar spray. Stone Lantern has a foliar spray, but it is a little pricey.
This does not fix the underlying condition that needs to be corrected, but it will stop the plant from dying hopefully.
Thanks for the information. It’s something I hadn’t considered before. I’ll look into the spray from Stone Lantern.