Sick Cotoneaster

I was hoping I could get some experienced eyes on my little Cotoneaster. It has just suddenly gone quite sick looking. It has been very vigorous for some time now and within the last several days has just started declining. I recently moved my trees out of the screened porch they were on and we have gotten a lot of rain lately so I was thinking maybe it's too wet. I also found a couple of spider mites crawling on it. So I misted it with some soapy water and as of today I cannot see any mites on the tree. It just continues to decline. Any suggestions?

It's hard to tell from the photos, but it appears somewhat similar to what I experienced with a small cotoneaster. It would put out new growth, but the leaves would turn yellow/brown and fall off prematurely. This went on for about 6 months...then it suddenly went downhill very rapidly - leaves on the lowest branches turned brown/black and died. I unpotted and found the root system had rotted out and the plant did not recover.

I'm not sure, but think if I had investigated the root system sooner I may have been able to save it. So - if this was my tree, I'd probably unpot it and have a look at the roots as a first step.

When was it last repotted and what type of soil is it in?

Will be interested to see what others think.

It was root rot. It was in a mixture of Turface, chicken grit and pine bark mulch. The soil was very wet. I used a flexible screen material to cover the drainage holes and it was all bunched up. So I think the drainage holes were partially plugged preventing the water from draining well. I have hope that there is still enough root to sustain the tree. We will see. Lessons have been learned. There is no teacher like experience.

After Azalea, Cotoneaster is my most numerous kill. I have learned that its important to give (at least in upstate NY) a generous ammount of foliage to heal damage to the roots when repotting them and yet still leave a good rootball with fines feeder roots. You can always cut back once vigor is established. If the roots aren't maintained by vigorous top growth the excess water just leads to rot under the soil line. They also need to dry out between waterings and are extremely drought tolerant.

Though a tough and resilient species I find as you have that their achilles heal is their roots. Hit some garden centers and grab a few cheapies to play with (you might even find a nicer one than what you had) and practice on those.
-Jay

Probably good advice Jay. And I thought golf was a tough hobby to pick up.('')