Evergreen Azaleas are sick (and maybe my little rhodo)

Pittsburgh, PA(Zone 6a)

Hi, I have 3 "Purple Gem" azaleas in my front yard that are about 1 foot tall. I just planted them in late spring. They were looking great and grew lots of new leaves. However, in the last couple of weeks, they've started looking ill. The lower halves of all three plants are turning brown, and the leaves midway up are curling. They are in clay soil (though we put in plenty of good soil around them when we planted) and they are in part sun facing north. Most of the sun is morning sun.

We also planted a large-leaf rhodo at the same time, and it's leaves are curling. This rhodo is about three feet tall.

Finally, there's a HUGE rhodo (15 feet) to the west of them that gets the afternoon sun. Unlike the others, it's doing great.

Are they sick? Too much water? Too little light? Wrong nutrients? All the other plants in the bed are looking great (hostas, toad lillies, coral bells, and foamflower). Please help! I'm afraid we're going to loose them and I'm not sure why.

Barnesville, GA(Zone 7b)

Difficult to tell without seeing a pic. Azaleas need to be planted a little higher than most plants (their roots are very shallow). We are usually told to plant where the soil level is the same as what is in the pot........not so with azaleas, you may have them too deep. They also like acidic soil. Sounds like they are not getting too much sun if it is just morning sun.

Dublin, CA(Zone 9a)

A picture would definitely help, but another possibility would be a watering problem or fungal issue caused by too much water. If you amended a small area right around the plant but the soil right outside that area is heavy clay, you can get the "clay pot" effect where you water but then the water has a hard time draining out of the planting hole into the soil, so its roots end up sitting in water way too much of the time.

Pittsburgh, PA(Zone 6a)

Here's a picture of the dying rhodo. It's gotten worse in the last week.

Thumbnail by ciera
Pittsburgh, PA(Zone 6a)

Here's a picture of one of the Purple Gems. They seem to be dying from the bottom up, but as you can see, some of the top leaves have curled too.

Thumbnail by ciera
Pittsburgh, PA(Zone 6a)

One last picture showing the bed. This was taken in the afternoon. In the morning, they get a couple hours of direct light.

Thumbnail by ciera
Dublin, CA(Zone 9a)

It could be root rot or something along those lines, I'm not sure if it's just general root rot from too much water or if it's one of the soil-born fungi that can infect plants in that family (although often those will only infect the plant if it's too wet also). I don't know if it's just the picture or if this is real, but in the picture of one of the Purple Gems, it looks like the soil might be piled too high around the plant--could they have been planted too deep? That could definitely cause problems. If they're not planted too deep, it could be the "clay pot" effect which I think I mentioned earlier--this can happen when you have heavy clay soil and you amend just the hole that you're putting the plant in (vs doing more extensive amendments over a much larger area of the bed). I'd try sticking your finger down a couple inches into the soil and see how it feels, if you find it's really wet then it probably was a watering issue that cause a fungal problem.

It also looks like there's a lot of mud on the leaves--since the leaves don't seem spotted this may not have been what caused your problem, but if there are fungal spores around in the soil and you splash soil up onto the leaves like that when you water, you can get fungal problems that way too, so you'd be better off next time putting down some mulch under the shrubs and being careful not to splash back up on the leaves when you're watering. Watering in the evening will also help to make this problem worse.

Pittsburgh, PA(Zone 6a)

Thanks! There's some clay clods lying around the bed, but the stems are clear. We actually haven't had to water them at all yet, we've had WAY too much rain this year. (My basil nearly died from too much water.) However, our gutters don't work well so they're probably a lot of water splashing around on them. I'll try mulching.

I did notice one odd thing. I tried to determine whether the soil was wet. The clay is definitely wet. However, the soil around the plants themselves feel a little dry. Actually, there was such a mass of roots that I couldn't stick my finger down in the area around the plant. There's just a mass of fibrous little roots everywhere.

Dublin, CA(Zone 9a)

If you've had a lot of rain lately and you have gutters splashing water down there that could definitely have caused them to get too much water (you'd be amazed at the volume of water that rolls off a roof!) I'd definitely get the gutters fixed so that doesn't happen anymore. As far as your observations when you tried to test your soil for moisture...the clay is naturally going to stay wet longer than the potting mix that the plant came in or the amendments that you put in the hole, that's probably why you're noticing that. But if the clay is really wet and your plant's roots are growing into the clay or up next to the clay, then they can be too wet too (part of the "clay pot" effect).

Since the roots are feeling so tight I also wonder if your plants are becoming rootbound in their holes--that's another side effect of the "clay pot". You've got a nice cushy amended planting hole, and then you have nasty clay soil, so the plant's roots would much rather stay in the nice amended soil so they keep growing round and round the planting hole rather than growing out into the soil. My personal preference when planting trees and shrubs is to dig a hole in my native soil, shake off as much of the container soil as possible, and plop the plant directly into the native soil. Trees and shrubs have extensive enough root systems that they are going to need to go out into your soil eventually, and if you plant them right into it then they have no choice. And also being in the native soil means that the moisture level around the plant will be consistent too, not like what I think is happening in your situation where the container mix that the plant came in is dry but the clay around it is soaking wet. There are other schools of thought on planting, a lot of people say you ought to amend and I'm in favor of amending too if you can do it to a good depth across the whole bed or if you're planting annuals and perennials that have smaller root systems, but for trees and shrubs I am not a fan of just amending the planting hole, particularly in clay soil I think it causes more problems in the long run.

Woodway, TX(Zone 8a)

Is your soil highly acidic? If not, you need to remove the clay down to about 8 inches and replace it with a soilless mix of half Canadian sphagnum peat moss and half pine bark mulch. Build the bed up several inches above grade. Azaleas have a quite shallow root system, and need excellent drainage. They must have acidity either from the native soil or from the organic matter I mentioned. If the bed is built up, it can drain even if you have excessive rains. If you're not sure of the pH of your soil, it would be worth the money to have a soil test done. Putting in azaleas is costly and a lot of work, and you need to know how to meet their needs properly.

Pittsburgh, PA(Zone 6a)

I have not tested the soil yet, but I think it should be fairly acidic. There used to be pine trees growing in this spot, and a lot of the stump was ground into the soil.

So, assuming it is root rot, what can I do to fix it? Dig them up, shake out the roots, and replant? It's become fairly hot now, and I'm afraid of sending them into shock, but they're not doing well as is.

Dublin, CA(Zone 9a)

Usually if the soil pH is too high the first thing you'll notice is the leaves looking chlorotic (veins stay green, but the rest of the leaf turns yellow, particularly on new growth). I don't notice that on your plants so at the very least I don't think it's your primary problem. Honestly I'm not sure what the best thing is to do--in the garden it's usually best if you can leave them where they are and let things dry out, or if you do dig them up don't replant them in the garden, put them in pots and move them to a shady location and then put them in the garden at a more appropriate time of year. I'd probably contact your county extension office--they can help diagnose the problem (is it just general root rot, or is it a fungus that infects this family of plants in which case you can't plant rhodies/azaleas there again, etc) and they can also advise you better on if there's anything you can do about it.

(Zone 5b)

I had 3 of those purple gems, planted by previous owners on the west side, in baking hot sun all day, they all struggled & died before I could move them. There were white azaleas in there with them, they did better with the onslaught of sun and survived a move last month to a raised area on the north side. The root systems of these azaleas was also wildly tangled & massed, I think because there was so much plastic weed barrier in there, layers of the stuff! I had a heck of a time pulling everything out. I had to cut up one of the white azaleas, I couldn't get the mess of roots & weed barrier apart. Maybe with clay soil you should raise the beds.

Woodway, TX(Zone 8a)

Azaleas are not going to be healthy and attractive in clay soil, raised or not. That is not negotiable. They require acidity, humus, and excellent drainage. If you have neutral or alkaline soil, you are fighting a battle that for most people is not worth it. Dwarf crape myrtles give excellent color and tolerate alkalinity quite well. Sometimes we have to realize that we can't grow EVERYTHING. No one can.

Barnesville, GA(Zone 7b)

Clay soil needs ground pine bark to make it "plantable" for azaleas and they need to be planted slightly above soil level.

Pittsburgh, PA(Zone 6a)

ecrane, thanks for the help. I think I'm going to repot them so I can keep a close eye on them. I'll replant when the weather starts to look a little more normal. We had triple our average amount of rain in May and double in June. The poor things haven't dried out since I planted.

Lynnie, the tag on ours was very specific about morning-only sun for this variety. They are beautiful when they bloom if you have an eastern or northern exposure.

dp, based on what I've seen around here, azaleas and rhodos do great in clay. We have a 15 foot rhodo that's quite happy, and a 4 foot azalea that we transplanted directly into clay and has only gotten happier. Rhodos also grow in the wild around here, and the native soil is red clay, so I think they rather like it.

I think ecrane hit it though; my one happy transplant went directly into clay and was practically bare-root when we transplanted. The others still are in the nursery soil. I'll pot them and try again in fall.

(Zone 5b)

you're right, Ciera, I think the people who planted the shrubs were in too much of a hurry to get the house on the market to care where they put them....the beds in front were narrow, 3 foot beds, with 8 shrubs stuffed in each, 2 deep. None of them looked too good! I have been creating big beds & trying to plant them with appropriate stuff & get it to look nice, it's hard work for someone like me who has no clue what she's doing! lol I love this website.
good luck with your little gems! hopefully it's the rain that got them down.

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