We suffered a long cold winter out here in Long Island NY. My rhododendrons leaves are brown and falling off. Should i assume they are dead or should i fertilize and hope for rebirth??

Answer #2 · Maple Tree's Answer · ali-Great close up picture. The burning of the leaves is a definite indication of winter damage. Fortunately it does look as though a lot of new growth is appearing. I would wait a couple of weeks to see how much of the plant has survived. I'm thinking most of the plant will recover. In a couple of weeks I would cut out any of the old or damaged stems that have not sprouted new growth and remove any damaged leaves still on the plant. The plant looks as though it could use a heavier pruning to give it a more dense fuller appearance and clean out old stems that may be interferring with others. I think I would wait until next year after this years recovery to do any heavy pruning. There appears to be some spotting of leaves but not sure if this may be a fungal disease or not. Keep your eye on the leaves looking for black or brown spots and yellowing of the leaves appearing. This could be a fungal disease normally caused by to much moisture. Many have received a lot of rain this year so make sure the soil is moist but never wet or saturated. If spotting of the leaves appears a fungicide treatment may be needed. Fungal disease normally discolors the foliage but usually will not hurt or kill a mature plant. Let me know in a couple of weeks how the plant is doing.

John)

Answer #1 · Maple Tree's Answer · Hi ali-I wouldn't assume your rhododendrons are dead yet. Unusually cold temperatures especially with some drying winds can do damage but not necessarily kill the plants. You can scatch small spots off the outer layer or bark of the stems to see if the underlying tissue is still green. If it is brown that portion of the plant is dead. I would only remove any browning leaves and dead stems. Moving down the stems cut out any dead growth until you reach areas of the stems that are still green. Always try and prune back to green wood cutting off the stem just above a dormant bud. If stems are still green and still living only the damaged leaves can be removed. The living stems will still sprout new leaves. Many times only the upper portion of the plants sustain most of the damage and the lower part of the plant will sprout new growth. The rhododendrons have shallow root systems therefore unusually cold temperatures can kill the entire plant if not mulched well or have a layer of snow as an insulator. Rhododendrons can also be cut back to within 6 to 8 inches of the ground if need be as in rejuvenation pruning. If you find only living tissue low to the ground I would most likely replace the plants. Many plants will recover from this drastic pruning but not all will survive. Drastic pruning such as this should be done in the winter when the plant is dormant. It may also be a couple of years before the plant will recover enough to produce flowers again if it needs this drastic pruning. At this time check to see how much of the plant is living and hold up on any fertilization at this time. Ferilization, forcing new growth, may possibly add to the plants stress. After new growth appears fertilization can be done.

Let me know what you find when checking the branching for living green tissue. You can also upload a picture of the plants if you would like. Above this answer and to the right of your name below your question you will see where you can upload any picture you have saved on your computer.

http://www.gardenality.com/Articles/976/How-To-Info/Pruning/How-To-Prune-A-Large-Leaved-Rhododendron/default.html

John)