Help with gardenia!

I am not sure what forum to post this on but since the gardenia is a shrub I will try this one. I am having a very strange problem. I bought 6 miniature gardenias (I think it was about June) from a home depot. They were not growing at all for a while and then all of a sudden two of them began to look droopy and pale, then yellow, then dead. the other 4 were fine. then two more started looking bad and the other two are growing and fixing to bloom. There is a kind of pattern to the ones that go bad. It is like I had a row of them... X X X X X X Then the Ist and 4th died so I had _ X X _ X X and now it is the 2nd and 4th. So each time there is at least one healthy plant between the two sick ones. Everything else in my yard is fine with the exception of a border of dusty miller at the edge of my patio. They are dying one at a time, and not like from one end to the other but staggered. Out of 12 I am on the 3rd one starting to die. Where the dusty miller is I had dusty miller before that had been there for several years, but had gotten rather overgrown and not pretty and neat. When I took them out I planted four or five huecheras there and they started to die one at a time, so I moved them to another bed but they died anyway. (one at a time) In the case of the huecherras the nursery said I probably watered them too much becasue they rot easily. The gardenias and the dusty miller are not in the same area of my yard. I do not see any type of pest or mildew or anything on them. I water and feed them the same as I do everything else.

I have two questions. Does anyone know what might be the cause of this? And does anyone know what I might do about it?

I also planted a couple groundcover-form gardenias earlier in the year, and they went through a period of yellowing foliage and looking pretty miserable. Something I read suggested the yellow foliage is a sign of iron deficiency; so I watered with acidifier/iron supplement for a while, and they perked up beautifully. Might be worth trying for yours; they like acid soil, so I can't imagine it could hurt.

If the gardenia has root rot can it be saved? Will H2O2 help? Is root rot contagious?

This message was edited Sep 12, 2006 6:57 AM

A picture would really help--yellowing leaves could be chlorosis which means it needs iron, or it could be a sign of root rot, or it could be something else entirely, and a picture could help us figure out which one. If the leaves that are yellowing are the new leaves, and they are yellow but the veins still look greenish, then it's chlorosis, otherwise if it's the older leaves or they're totally yellow then it's something else. If it's chlorosis, iron is the way to go, but if your soil is alkaline you'll need to acidify it some too or else the plant can't absorb the iron.

As far as your question about root rot, whether they can be saved or not depends on how far gone they are. Some people have had good experience with peroxide, but if the rot is too bad then even that probably won't help. And root rot's not really contagious, except in the sense that it's usually caused by overwatering, and if you're overwatering one of them you're probably overwatering all of them so if you don't stop they'd eventually all get it. How often are you watering? Gardenias do like things on the wetter side, so it's harder to overwater them than it is with some other plants, but definitely not impossible! Before you go to water next time, I would stick your finger down in the soil a few inches, and if it still feels wet then don't water.

The other possibility is too much heat/sun--I know that most gardenias come with a tag saying they like full sun, but in a climate like yours that's just not true. There have been some other gardenia discussions, maybe on the Fragrant Gardening forum? where people have talked about this, and the majority of people in climates like yours and mine need to grow them where they get PM shade. So if you're growing yours in mostly sun that could be it.

Mine are getting PM shade. I had a regular gardenia in that same area that did very well. We cut it down this summer because we are doing all of our foundation plantings over.

The yellowing and now browning leaves are the old ones. And the whole plant is not bright green like the others. If it is root rot from overwatering, why is it going from plant to plant? I had been wateriing just about every day because we had 100* plus weather and no rain in forever. It has cooled off some and it rained once so I have cut down and water about every other day.

I don't think we've established for sure that it's root rot, just that it is one possibility. But if that is it, it could seem to spread from plant to plant because of slightly different drainage patterns, slightly different amts of water made some rot faster than others. However, yellowing leaves can mean many things, you've eliminated chlorosis because of which leaves it is that are turning yellow, but I'm not entirely convinced that the sun/heat isn't a problem, and there are potentially other things that could make the leaves yellow as well. After re-reading your original post, I think the real problem is that you planted them in summertime and they didn't have time to establish themselves properly before hot weather set in. What happens in this case is that the roots of the newly planted shrubs aren't able to take up as much water as they would if the plant were well established, and this does two bad things for you. The first bad thing is that the plant is in effect under-watered because even if you water it, the roots can't take up as much as the plant needs (especially if the weather's super hot), and then the second bad thing is that the plant then looks like it needs water, so you water it more, but since the roots can't take it up, if you have poor drainage it'll just sit there and can cause root rot. So it can die of over and under-watering all at the same time! And it could happen at different times for different plants because some of them may have had more/better root systems to begin with, which would help them hold out longer than others. I would check for the overwatering piece by sticking your finger down a few inches into the soil just before the next time you would plan on watering, and if the soil feels moist then don't water just yet. The under-watering because of the roots not being established should not be as much of a problem as you get into the cooler temps of fall, so hopefully any of the plants that aren't completely dead yet should be able to resurrect themselves, then next year they should be fine since they will have had time to establish themselves.

I have put the really poor looking gardenia into intensive care today. I have more than just yellow leaves. The other plants are glossy green, this one is faded and dull and whole stems are brown. I decided that it was probably not going to make it anyway, so I dug it up so I could look at the roots, which by the way seemed fine. And there are a lot of them. White healthy looking roots, not a black one in the bunch. No sign of any other kind of damage. So I put it in a pot and cut off the dead branches, sprayed with and antifungal inseticide that I use on roses, watered it with a transplanting solution that reduces shock, and put it in a shady location. I have examined the leaves on the brown, yellow and green parts and can see no pests, no spots or blotches of any kind. It is a mystery to me. If anyone can think of anything else I can do for it, let me know...
Thanks,
Carol

If the roots look fine and you don't see signs of any pests, I'll stick with my theory of its roots not being able to take up enough water to keep it from shrivelling in the heat because it wasn't well established yet, or possibly even the once a day watering during the heat wave wasn't quite enough, especially if your soil is more sandy rather than clay. Hopefully now that you've removed it from the stressful situation it'll perk up.