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Entomosporium leaf spot of photinia and Indian hawthorn


ENTOMOSPORIUM LEAF SPOT OF PHOTINIA AND INDIAN HAWTHORN
 


"There is no effective control for this very damaging disease.” That’s what is often said when the purple spots and yellow leaves show up on photinia and hawthorns. But – it’s not true.

 
First of all, understand that neither photinia nor Indian hawthorn can stand “wet feet” or tolerate poor drainage. Red tip photinia (Photinia fraseri) are particularly susceptible to root fungal diseases in poorly drained soil. Damage from root diseases can weaken plants making them more susceptible to problems such as leaf spot fungus. Fallen leaves can be removed, as they are a potential source of future infections, but are not the most significant source. Moving them could cause dispersal of more spores. I never do that. You may try covering fallen diseased leaves with cedar mulch to accelerate their decomposition and suppress the fungus.

 
For treatment, use a potassium bicarbonate spray on the foliage (1 rounded tablespoon per gallon water), 1% hydrogen peroxide or corn meal juice. It may be good to remove severely diseased plants that have also been damaged by cold injury and replace them with other plants not susceptible to the disease.  For plants that remain, aerate the root zone and while the holes are open, apply the soil amendments we use for bed preparation - compost, rock minerals like lava sand, greensand, zeolite and sugars like dry molasses and cornmeal. That’s basically the Sick Tree Treatment 

 
Although I wouldn’t plant any more red tip photinia, my photinia program, which evolved into the Sick Tree Treatment, can save the plants and bring them back into health.  If the root system of the plant is too damaged, then the plant may need to be removed. The reason for the acceleration of photinia problems is over-planting and the continued use of harsh synthetic fertilizers and toxic pesticides.  Not only do those products not solve the problem, they make it worse. The real problem is not the spots on the leaves, the subsequent chlorosis and then foliage die back.  These are merely symptoms of the real problem. Unhealthy roots are the problem.



 
Red tip photinia breeding led to this fatal flaw - weak roots that are highly susceptible to root fungal diseases. When the roots get in trouble, the symptoms start to appear on the foliage. Only the organic products that stimulate beneficial biological activity will help.  Many people have saved their plants with the Sick Tree Treatment and the basic organic program keeps them happy long term. For more details see - Sick Tree Treatment on https://www.dirtdoctor.com.








 

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