Answer: Pyracantha is generally problem free, but there are two diseases that might affect it:
Fire blight causes wilting and blackening of shoots and
the dead leaves hang on the twigs. There is no chemical
control. Prune out infected twigs well below the infected
Scab causes dark areas on the leaves that turn yellow,
then brown, then drop off. No chemical controls are
listed. Rake up and destroy infected leaves.
Aside from these two problems, there may be something within the soil that is affecting your plants. Dig down to see what's there, and make sure that the soil drains quickly (pyracantha detests wet feet!). If you want to grow pyracantha, take the safe road and choose another garden site, to avoid infecting a new plant if there's a soilborne pathogen lurking in the bed!
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