Yellowing and dropping of leaves is normal toward the end of the second summer on the small-leaved lepidote rhododendrons. These should have dense enough habit that this doesn't matter. The larger-leaved elepidote rhododendrons keep their leaves for 3 or 4 seasons. Like all evergreen plants, rhododendrons and azaleas periodically lose some of their foliage, and the leaves may turn yellow, red, or purple before they fall. Often the only leaves that remain are those that surround the flower buds at the tips of the branches. This characteristic is linked to the genetics of the parents used to breed garden azaleas. The degree of leaf coloration or loss is a function of parentage and not the severity of the winter. In unusually cold winters, certain azaleas may lose more leaves than they would in mild winters. Most diseases that harm rhododendrons cause the leaves to yellow, droop, curl, and eventually turn brown, but, oddly enough, they usually don't drop the leaves. Some things that can kill individual branches are: DROUGHT: Drought can cause entire branches or entire plants to die. We have had several years of drought here and we observe that if rhododendrons and azaleas are not watered during a drought some plants will die, but others will just have one section of the plant die. It seems to be the plants way to conserve what little moisture it has. Prolonged drought weakens plants and often results in the appearance of fungal cankers on the branches of older azaleas. Look for branches that wilt in hot, dry weather in late summer and be sure to water azaleas if drought drags on more than a few weeks. Prune out the affected branches to stop the spread of fungal canker diseases. BORERS: If a Rhododendron Stem Borer, Oberea myops, or Rhododendron Borer, Synanthedon rhododendri, is in a branch, the entire portions of a plant beyond (away from the roots) will wilt and die. Borers only affect the portion of the plant away from the roots from the borer. If the borer is in the main trunk, then the entire plant will wilt and die. The plant can be save by cutting off the area with the borer and letting the plant regenerate from the roots. There are no conventional insecticides that will kill stem borer larvae once they are inside the branches. The best control option for homeowners with only a few plants is to prune out and destroy wilting branches in early spring or late summer. FUNGUS: Buds and twigs becoming covered with silver-gray scales is caused by one of the water molds: Altenaria Blight or Botrytis Blight or Twig Blight and is easy to control with fungicide sprays and proper sanitation by removing and disposing of all dead material. Phytophthora cactorum causes the central vein of a leaf to turn brown and the discoloration extends to the petiole on tender new growth. The infections spreads outward from the midrib tissue and the leaf wilts. Infections are more severe on azaleas. Some varieties of rhododendrons are vulnerable (Chionoides, Catawbiense Album, Nova Zembla) and some are resistant (Roseum Elegans, Scintillation, PJM). Control of the disease is difficult. Since the infection goes from the roots to the tips, when you see the symptoms it is too late. To prevent it, use a raised bed with lots of sphagnum peat moss. Prevention with fungicides and careful control of exposure to high humidity may be practical. [Return to Problem Menu] Botryosphaeria dothidea causes leaves to turn dull green and then brown and roll and droop. Cankers form on branches which may girdle the branch. This is the most common disease of rhododendron in the landscape. A typical symptom of this fungal disease is scattered dying branches on an otherwise healthy plant. Leaves on infected stems turn brown, then droop and roll inward. These leaves often lay flat against the stem and will remain attached. The pathogen can infect all ages of stem tissue through wounds, pruning cuts, and leaf scars. Heat, drought stress, and winter injury can increase disease incidence. Cankers on branches can gradually grow through the wood until the stem becomes girdled. Diseased wood is reddish brown in appearance. Discolored wood viewed in longitudinal cross section often forms a wedge that points toward the center of the stem, and the pith may be darker brown than the surrounding wood. Sanitation and applying a fungicide such as metalaxyl (Subdue) after pruning my provide some control. Plants should be grown in partial shade, with mulch and kept well watered during dry periods. All dying branches should be promptly pruned out in dry weather and all discolored wood should be removed. Plants should also be protected from rough treatment during maintenance activities to prevent unnecessary wounds. [Return to Problem Menu] Phomopsis rhododendri symptoms vary from leaf spots to chlorosis and then browning of leaves which then wilt. Browning streaks extend down the stem to a wound. Fungicides such as metalaxyl (Subdue) should control an outbreak. Sanitation and applying a fungicide after pruning may provide control. [Return to Problem Menu] Rhizoctonia solani: causes small necrotic spots on leaves, which later become dark brown or black. Defoliation follows severe leaf spotting. The fungus is omnipresent in the soil and appears to be most virulent at high humidity levels. Microscopic examination of roots and crown are the surest diagnosis. Cultural practices to control this disease include improvement of drainage and avoidance of excess irrigation.

It needs more moisture. Camellias like contant moisture, not dry nor wet. Many of the roots are in the top few inches so you want to feel moisture at depth of 4" or so, not at 10". Insert a finger to a depth of 4" and see how it feels. If it feels wet, take no action. If it feels moist, do the same. If it feels dry or almost dry then water. Put about 3-4" of mulch and keep the pot away from windy areas. Test with the finger method daily for about two weeks. Every time that you water, make a note on a wall calendar. After two weeks, observe how often you are watering (every 2/3/4/etc days). Then make a habit to water on that same frequency. If the temps change more than 10 degrees and stay there, use the finger method again. Lack of moisture will cause the plant to drop the flower buds.

It's been so wet and cool in NJ so far this season. I still haven't planted out most of my Salvia Lady in Red and Coral Nymph. Ones in ground are just sitting there. They take off so fast once it warms up I'm not worried. The ones I potted up to 5" plastic pots are much larger and stronger than those in 3" Cow Pots which are water hogs and roots don't penetrate as promised. I didn't know TMV was a problem with Salvia! I just read something about it when trying to figure out how to grow Tomatoes for the first time. They warned about smokers touching certain vegetable plants and TMV. Being a smoker (bad, I know) I'll be using my tub of bleach/water solution I keep on the patio before I touch Salvia in addition to washing my hands/tools for cleaning off dirt, possible bacteria/viruses and while working on roses. The first couple weeks of rain were okay on plants but they're not getting a chance to dry out by now with more rain. I figure I'm lucky when it rains after I plant things out because I don't have to lug around watering cans for a few days. There seems to be a lot of aphids this year. They've even been landing on my arms which never happened before. I can give roses hard water spray in morning but not new little plants. Weather's been so fritzy there haven't even been bees or Cabbage Whites on Salvia Victoria, Caradonna or May Night this year while they mobbed them last year. Guess patience with Mother Nature, which we can't control, is in order.

I'm in SNJ and I've had horrible blossom drop due to the humid weather... I have fruit, and am harvesting cherries and grapes & currants, and hope to pick some early toms by monday.... but it is sparse due to all my lost blossoms. Maybe overwatering? I water only once a week, deeply w/ a soaker hose. Check your soil, it just might be too wet... from what I understand, if the soil is too wet for too long, the plants can get stunted, the roots rot, or at the very least become water logged and not be able to take up nutrition. I also am learning that i 'loved' my plants too hard last year and fertilized too much... I think that can cause some of the symptoms you're referring to as well. did you amend your soil w/ dried blood? I think thats pure N, and that would make for a bushy plant but little fruit. Pictures would help I'm sure. I'm not much help though, I'm only in my second year of growing and I'm having tons of problems myself. good luck.