How long will fireblight remain in the soil?
Question:
I have a crab apple that was diagnosed with Fireblight. The first symptoms appeared several years ago. I’m planning to have it removed. How long will the fireblight remain in the soil? When can I plant something else in the general area and what should that be? I’d like a pretty flowering, small tree.
Answer:
Thank you for reaching out to the UMaine Cooperative Extension with your question.
Ugh, I’m so sorry to hear about the fire blight on your crab–it can be a maddening disease. Technically, because the pathogen is bacterial, it doesn’t really persist in the soil. However, there is almost always some leftover plant material from the removed tree that could harbor living bacteria for a season or two, and if there is another plant (either cultivated or wild) in the area with fire blight, that could be source of recurring infection, too. That said, planting something resistant to a known pathogen is one of our favorite recommendations for dealing with plant disease (non-toxic and sustainable!), so I think it’s a good idea.
So, you have two broad options. One, if you would really like to plant another apple or crabapple there, choose a resistant cultivar for them (lists in those links). Just keep in mind that if you did get a reinfection (which should be rarer and/or milder with a resistance), you might need to pursue the scouting, pruning, and copper mitigations strategies detailed on this great resource page from the Cornell Extension. Alternatively, and more reliably, you could plant a non-rose family ornamental shrub or tree, as fire blight only affect members of that group (so dogwood, viburnum, winterberry, redbud, etc., would all be fine choices).
Happy gardening.