Almond, Flowering (Prunus)
Plant Health Problems
Diseases caused by Fungi:
Brown rot, Monilinia fructicola.
Flowers wither and branches die soon after blossom time. The fungus is often found fruiting on the dead flowers as grayish brown tufts of mold. The same organism causes brown rot on peaches, cherries, and other stone fruits. Disease is favored by humid wet weather during flowering and the spores are carried by wind, rain, and pollinating insects.
This disease can be managed by attention to planting site and by locating the planting away from other stone fruits or ornamental cherries and plums in order to minimize the spread of spores from tree to tree. It is also important to prune and remove infected twigs and branches. Control can also be achieved with the use of fungicide sprays applied when new growth emerges in the spring. Several applications may be necessary, especially when wet weather persists. Among the compounds registered for use in Connecticut are captan, chlorothalonil, iprodione, and sulfur. Consult the label for dosage rates and safety precautions.
Diseases caused by Physiological/Environmental Factors:
Winter injury, environmental.
Symptoms include sudden wilt, death of twigs and branches, and plant collapse in late spring and early summer. This plant is often considered to be marginally hardy in Connecticut so extremes in temperature during the winter contribute to damage to the buds and wood.
This type of injury can be avoided by attention to planting site and by maximizing plant vigor by following sound cultural practices. It is also helpful to prune and remove any symptomatic tissues as soon as they appear. For more information, see the fact sheet on Winter Injury on Woody Ornamentals.
For insect problems see Peach.