Knowledgebase
Crabapple tree in trouble #878754
Asked July 25, 2024, 2:20 PM EDT
Orleans County Vermont
Expert Response
Barbara
Thanks for your question. The photos are helpful but it would be ideal if you can send one or two that of individual leaves that have the spotting you mentioned to get a better idea of what may be happening.
Thanks,
Andrea
Barbara Postman
Barbara
I thought I'd go ahead and give you a couple of potential answers to what is going on with your crabapples to maybe get you an answer before the weekend.
Wet weather could be contributing plants can drop leaves from overwatering so your thought on 'wet feet' is a reasonable one. In looking at the location of your tree it doesn't seem like that area would be too wet. Clay does drain less well than other soils, but crabapples can thrive here in the Champlain Valley where I live and the clay is deep!
The wet weather, however, can contribute to diseases especially those caused by fungi. A common one is 'Apple Scab' that can cause leaf blotching and subsequent dropping of infected leaves. Here is how the condition is described:
- Leaf spots are round, olive-green, and up to 1/2" across
- Spots are velvet-like with fringed borders
- As they age, spots turn dark brown and get bigger/grow together
- Spots often form along the leaf veins
- Leaves with many spots turn yellow and drop by mid-summer
The condition can also impact the fruit - they show similar spots and if infected early can become deformed and cracked.
Spores can be carried by the wind (and likely built up with our very wet summer last year) but you should rake up the leaves and fruit and remove from the area (burn or compost) to decrease the risk of infection next year. On a mature tree the condition usually doesn't kill the tree and doing nothing is often recommended, but on your young tree there is reason for concern. You might want to consider fertilizing the tree and if the weather gets dry, you want to be sure to provide adequate water (trees need extra watering for at least 2 years after planting).
In the future you can look into scab-resistant cultivars of crabapples.
I'm attaching a photo here for you to compare to your leaves. If it doesn't look like this is the problem with your crabapple, please do send a photo or two and I'll look into what else might be causing this problem.
By the way, it looks like this will be a lovely garden as all the plantings mature!
Barbara,
I've asked the program folks if you can drop the leaves off and waiting for a reply. I also sent a photo of apple scab that you compare your leaves to.
Best,
Andrea
We had the UVM Plant Pathologist take a look at your submission, and following is the info. she provided:
To me, the plant looks overall chlorotic which I suspect is an issue in the root system. It may be just trying to get established but there may also be root rot in there making things worse from all the wet weather.
Apple do not like wet feet. There is not much you can do this late in the season. If it was earlier I would recommend fertilizer, but it is getting too close to fall to give it much Nitrogen now. I think you have to just cross your fingers at this point and see how it comes out next spring. I would give it some 10-10-10 or ProGro 5-4-3 in May and hopefully it will recover.
I hope this information is helpful and wish you luck that the tree looks better next season.
Hi Barbara,
Sorry to hear that your crabapple tree continues to worsen.
It is best to deal with drainage issues before planting. I'm including some references for you on that if you have other wet areas you want to plant in the future. Additionally there are trees, shrubs, and grasses that don't mind 'wet feet' that you could consider - these are also noted in the attachment.
However you can try in increase drainage around the tree now and hope that its root system is not already succumbing to rot. While piping and soil amendments can improve drainage, they work best before you plant. However, as you mentioned, you can try to direct the water away from the area. One interesting option is to create a rain garden. Here is a link to a very comprehensive 'how to' from UMass Amherst. It also outlines the other good thing about rain gardens: they improve overall water quality by allowing stormwater time to be filtered of pollutants. And they can be very attractive!
https://ag.umass.edu/landscape/fact-sheets/rain-gardens-way-to-improve-water-quality
I hope that you can save your current plantings and good luck with the rest of your landscaping endeavors!
Hi Barbara,
Sorry to hear that your crabapple tree continues to worsen.
It is best to deal with drainage issues before planting. I'm including some references for you on that if you have other wet areas you want to plant in the future. Additionally there are trees, shrubs, and grasses that don't mind 'wet feet' that you could consider - these are also noted in the attachment.
However you can try in increase drainage around the tree now and hope that its root system is not already succumbing to rot. While piping and soil amendments can improve drainage, they work best before you plant. However, as you mentioned, you can try to direct the water away from the area. One interesting option is to create a rain garden. Here is a link to a very comprehensive 'how to' from UMass Amherst. It also outlines the other good thing about rain gardens: they improve overall water quality by allowing stormwater time to be filtered of pollutants. And they can be very attractive!
https://ag.umass.edu/landscape/fact-sheets/rain-gardens-way-to-improve-water-quality
I hope that you can save your current plantings and good luck with the rest of your landscaping endeavors!
