Help saver my Rhody!

[April Manier]

Our Rhody (Rhododendron) recently has begun crisping the edges of the leaves and a white fungus has appeared around the flower buds. It has spread to another nearby bed fellow. Anyone know what fungicide to use. We needn't be organic in that part of the yard as we are far enough from the field.

 

[Smart Red]

Now you're scaring me. For a plant that WON'T grow around here, our Rhodies have long been the most carefree shrubs on the property. Here are a couple of possible areas of concern.

Fungi : Powdery Mildew

Powdery Mildew is usually found on plants that do not have enough air circulation or adequate light. Problems are worse where nights are cool and days are warm and humid. The powdery white or gray fungus is usually found on the upper surface of leaves or fruit. Leaves will often turn yellow or brown, curl up, and drop off. New foliage emerges crinkled and distorted. Fruit will be dwarfed and often drops early.

Prevention and Control: Plant resistant varieties and space plants properly so they receive adequate light and air circulation. Always water from below, keeping water off the foliage. This is paramount for roses. Go easy on the nitrogen fertilizer. Apply fungicides according to label directions before problem becomes severe and follow directions exactly, not missing any required treatments. Sanitation is a must - clean up and remove all leaves, flowers, or debris in the fall and destroy.

Pest : Mealybugs

Small, wingless, dull-white, soft-bodied insects that produce a waxy powdery covering. They have piercing/sucking mouth parts that suck the sap out of plant tissue. Mealybugs often look like small pieces of cotton and they tend to congregate where leaves and stems branch. They attack a wide range of plants. The young tend to move around until they find a suitable feeding spot, then they hang out in colonies and feed. Mealybugs can weaken a plant leading to yellow foliage and leaf drop. They also produce a sweet substance called honeydew (coveted by ants) which can lead to an unattractive black surface fungal growth called sooty mold.
Prevention and Control: Isolate infested plants from those that are not. Consult your local garden center professional or the Cooperative Extension office in your county for a legal insecticide/chemical recommendation. Encourage natural enemies such as lady beetles in the garden to help reduce population levels of mealybugs.
(from YardGardener,com)

 

[April Manier]

it's not powdery mildew. This is Oregon, I can spot that a mile away. Need to break out old Textbook from horticulture. I've never had to do ANYTHING with my rhodies! This is weird!!!!!

 

[April Manier]

So I have done a bit of reading and many sites recommend Funginex. I have seen this. Copper and sulphur would be the organic treatments available./ I'll keep y'all posted.

 

[897tgigvib]

Rhododendrons do like that acidic soil...

Sulfur...acidic

Copper is very effective antifungal