Where in the world do you live? I will assume it is in the Southeastern USA since you are growing Encore Azaleas and they aren't available too many other places. These are evergreen azaleas that are bred to bloom in spring and again in fall.

All of the evergreen azaleas are native to Asia. They appear to be evergreen because they grow two sets of leaves each year. Evergreen azaleas have dimorphic leaves, known as spring and summer leaves. The spring leaves unfold at the beginning of the growing season and are dropped in autumn. Summer leaves emerge in early summer and are smaller, thicker, darker, and more leathery than spring leaves. They remain on the plant during the dormant period and drop in the spring, however, summer leaves may persist for several years in warm climates. Some "evergreen" azaleas are deciduous in colder climates. Sometimes this is called being semievergreen.

Yellowing and dropping of leaves is normal toward the end of the summer on some evergreen azaleas. These should have dense enough habit that this doesn't matter. Like all evergreen plants, 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.

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.

Wind and cold damage is indicated when the edges of the leaves become distorted and turn brown. This occurs frequently in plants that may be in a colder climate than recommended or in a location with severe exposure. Provide protection from winter winds and winter sun. Note, boron poisoning or fertilizer burn will create the same symptoms except uniformly over the plant rather than just on areas exposed to the sun and wind.

As with all plants, their are a number of factors. Here are a few:

Soil Drainage: azaleas need moist well drained soil.
Soil Acidity: azaleas require an acidic soil.
Walnut Roots: black walnut & butternut tree roots produce a substance that kills azaleas.

Here is a link that might be useful: How to grow azaleas.

Yes, I am in the southeast...the upper part of SC, 7b.

From what you've said, my azaleas are probably ok. There is one that I believe has bit the dust. Will wait until Spring to see what happens!

I lived in South Carolina for many years, and old growth azaleas are sometimes hit by fungus diseases. The two primary culprits are phytophthora and phomopsis. Both (either) can cause the symptoms that you describe. If you were to call your local extension office, they might even use the term 'azalea die-back', though they shouldn't without proper diagnostic testing. As you can clearly see by rhody's description, lots of things can cause those symptoms!

South Carolina has a plant clinic where, with your extension agent's assistance, you can send samples for testing. Only by laboratory screening can you dismiss a disease element, and I would certainly take advantage of the opportunity. Call or visit your local office for instructions about how to take the samples they need, how to package it, and for the forms that you need to fill out. They will mail it for you. There will be a small fee.

I live in UpState SC also and have noticed the same thing with my azaleas. They have been in the same location for over 10 years and appear to be as healthy as ever except for the brown leaves. Hubby reminded me that I worried over the same thing about three years ago AND that the following Spring was one of their best blooming seasons... I suppose it really would be good for me to start a journal to make notes of things like this.

Homegrownsc, how about also taking digital pictures in addition to making journal entries (for referencee purposes, three years in the future)? You could take one of the whole plant and two more close-ups showing the top and bottom of the leaves. When a stem is damaged, you could also take a picture of that too.

Keep the photos in a special folder under the main Windows folder 'My Documents' so you will "move" them when the current PC is replaced by a newer one.

An alternative to the digital pictures: you could also create a digital movie of yourself showing the problem and damage but that can be more complicated than it is worth. The advantage is there is more visual information and you can record yourself talking about the problem, the course of action that you took and why.

Luis

Excellent idea, Luis. The movies are a great idea when I'm really crunched for time but want a more detailed record...I'd be more likely to do that than to sit and write in enough detail to recall the specifics three or more years later.

Thanks!!

Hi, I am from Indiana and I have three Azalea bushes that are about 3 yrs. old. They bloomed wonderfully the fist summer we planted them. After the first winter, they turned brown and in the spring they were green again and didn't bloom very much. I didn't know to cover them when it frosted and I think that is why they did not bloom much. Now, they are very brown but I see a little green on the leaves. I have been covering them with a towel at night when it frosts. I thought they were dead but I'm not sure. I'll just wait and see if they bloom a lot this year. Does this happen to yours?

Hello, hoosiergirl28. Not here but our winter are so mild that most azaleas will be evergreen most years. In very cold environments like Zone 4, azaleas will loose their leaves and then leaf out when Spring temperatures return.

Leaf out and blooming occur at different times of the year and depends on the azalea variety that you have. If the plants regularly begin to leaf out or bloom at times when these get zapped by late frosts, the plants may not be hardy in your zone. Why? Well, because you end up with plants that do not bloom much or do not bloom at all. While the new tender leaves and the buds can be killed by the late frosts, the leaves will return but that just leaves you with a nice green plant year around. Under normal weather conditions, you should not be having to cover/protect them so much in order to make sure that the flower buds will not be affected.

Because azaleas originated from warmer locations, they have a hard time thriving in areas such as yours (Zone 4). Winter resistant hybrids have been developed that get can handle these problems. But to tell if your blooming problem is due to the weather, I was wondering if you could post the variety (name) of these azaleas? Perhaps from the plant label if you still have it?

If you really want to keep these shrubs, you may want to consider moving the plants to a more protected location where they get about 4rs of morning sun and stop fertilizing & pruning (if you do any pruning that is) in July. If it turns out that this particular variety does not do well in Zone 4, you could replace the plants by other varieties that are more resistant to winter damage.

In the meantime, maintain the soil well mulched (3-4" of acidic mulch) and moist, not wet or dry.

Here is a link that might be useful: Article from the University of Minnesota Landscape Arboretum

We planted encore azaleas last fall. They bloomed and again this spring. Now, one started getting silver leaves at the ends. He, then started dying. Almost gone, but still working with it. Now, one of my healthy ones has shown these same silver leaves at the tips. Now, I wonder, is this a disease they have?

In mid-September I planted seven Encore Azaleas at the same time as eight knock out rose bushes. The Azaleas are in three different beds in my front yard and none are in the same bed as my roses. Our home sits on a bed of sand, so drainage is not an issue. I used a good potting soil and peat moss when planting and spread pine needles around all the Azaleas. Today we noticed the leaves of the Azaleas are wilting. Their leaves have not turned color or fallen off, so we are not sure what is the problem. We have experienced two cold fronts in north Texas where the temp is in the 80s one day and plummets to the 50s the next. Lows have not hit freezing as of yet, but have come close. My roses are thriving, which is why I am concerned about my wilting Azaleas. This is my first time planting Azaleas so any insight would be much appreciated.

Your evergreen azaleas may exhibit a change in leaf color in Fall, but you don't want them to drop. Have you been supplying them with regular water?

Did you rough up or open the rootballs when installing these, often potted azaleas have a tightly compacted rootball in the nursery containers when you purchase them. Your azaleas (without a photo) sound as though they are too dry. Its entirely easy to water the area they are in without water actually penetrating the original rootball, and this could be particularly true in your fast draining sandy soil.

Thank you for the response. We regularly run our sprinkler system, but have scaled back a bit with fall coming. I did break up the root balls, but maybe not enough. Out of the seven Azaleas, three share the same bed and look far worse than the others. Those three are really showing signs of water shortage, as the leaves are brown and the branches are turning brown. I am pouring on the water in hopes of saving them.

septmac, another thought if you are not familiar with azaleas and planting them, their roots don't function well if they have been planted too deeply. Are they in the ground at the same level or even slightly higher than they were growing in their pots? Higher is important where drainage is on the slow side, but even in your sandier soil you wouldn't want them in the ground noticeably deeper than they had been in their pots. Your pine needle mulch does not count towards depth so don't consider that.