Possible Fungus (?) Threatening Whole Patio- Help!

[KJSegall]

Hello- this is my first post here. I'm hoping someone can help.

I have a patio garden that has grown very well, even with the Florida summer. However very recently I noticed the leaves on some of my plants growing brown edges very rapidly- overnight, actually. My garden is a mix of herbs and 'decorative' plants.

It started after a rain with some of my oregano, geranium, mint, and marjoram (the mint and marjoram are in the same holder; there is some thyme in the same holder as the oregano, but with the tiny leaves it was hard to tell if they were affected as well). Again it was after an evening shower, the next morning I was startled by how quickly the tips of the leaves had turned brown.

I had recently used Eliminator brand fire ant killer (I know, dumb with the herbs, I just won't cook with them for a while) to clear out a hefty ant infestation, and at first I thought maybe I had used too much in these particular pots and would just have to 'wait out' the damage. However today there was another late afternoon shower, and I found that several other plants had almost instantaneously developed brown edges- including some coleus cuttings that are sitting in water and were never exposed to the ant poison.

I'm worried that there must be some sort of fungus spreading through my 'garden'- its still somewhat sporatic, with what I would guess to be half of the plants affected. But as much as I search through Google, ask those wiser, etc., I cannot find ANYTHING that corresponds with these 'symptoms'.

The plants thus far affected are geranium, coleus, hypoestes (one, but not seemingly another, yet...), vinca, parsley, mint (2 seperate mint plants in 2 seperate containers), oregano, marjoram, sage, and dill. I live in the Tampa FL region. The plants show no additional signs of this being overwatering, and I can basically guarantee they are not underwatered. (Also, note that this damage seems to appear almost instantaneously, which in my experience poor watering damage is more gradual). Both 'spurts' of this appeared after a moderate rain- perhaps something getting spread around by the splashing?

Can anyone at all help me figure out what in the world is happening, and what I can do about it? I hate to lose my entire 'garden'...

 

[Chuck]

It sure looks like too much water too often

 

[Mrsclem]

Doesn't look like a fungus to me ( just my opinion). Is it possible it could be damage from the ant treatment? Some pesticides can burn plants. You also may want to check with the company that makes it to see it there is any toxins that could remain in your herbs long term. I used a vole treatment in my flower bed that had herbs that had a strong poison in it and now the herbs are no longer safe to use.

 

[Chuck]

Bifenthrin is the active ingredient in this poison. The following link explains what this product does and does not do. IT IS NON TOXIC TO PLANTS so your plant problems aren't caused by this product. This product is not absorbed in foliage nor is it translocated in the plant. If you want a 100% safe way to quickly eliminate fire ants use a product that has spinosad as its active ingredient and use it as a soil drench.
http://npic.orst.edu/factsheets/archive/biftech.html

 

[KJSegall]

The thing is, the geranium today has some very dry and crinkly leaves- with the rain yesterday, its not under- watered, but the symptoms just don't seem like over-watering (in my humble experience, and I did lose some plants to that when we had a tropical storm come through earlier this year).

 

[Chuck]

The thing is, the geranium today has some very dry and crinkly leaves- with the rain yesterday, its not under-View attachment 40036 View attachment 40037 watered, but the symptoms just don't seem like over-watering (in my humble experience, and I did lose some plants to that when we had a tropical storm come through earlier this year).

Could it possibly be root bound and not able to uptake water when delivered?

 

[KJSegall]

I just checked- seems like very healthy roots, certainly not root bound, there was some room to grow.

 

[Sheal]

How wet is the soil KJ? It's possible that they've had too much rain and not able to dry out in-between. Have the pots got good drainage?

 

[KJSegall]

They seem to drain well- the thing is, the leaves are crisp, not soft and wilted, so it doesn't strike me as overwatering, unless it is possible it still is without that tell-tale sign?

 

[Sheal]

The leaves will be brown and crisp if over watered but soft and wilting if under watered. There is also the possibility of leaf scorch, when the heat of the sun burns the leaves while they are still wet, but this doesn't usually happen with rain water.

 

[KJSegall]

The thing about leaf scorch is that some of these plants are well shaded. This is what's so frustrating- just when it seems like there's an answer, one of the affected plants disproves the theory.