Louise S
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Rosemary wilting (Spider mites, I think)

Dear gardeners,

Hello! I recently bought a rosemary plant, about a week ago. Two days ago I noticed that the plant was wilting, and that there were tiny brown dots moving across the leaves. I checked for webs and saw a few, hardly noticeable though. My first guess was that they were spider mites, so I gave the plant a good shower. The larger mites disappeared, but the smaller ones remained, and the plant isn't looking any better! In fact, more leaves have turned brown. Any suggestions?

I've soaked garlic, onion and chilli in water and will use it when 24 hours are over.

Thanks in advance!!

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digitS'
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Spider mites certainly like rosemary, Louise.

Finding them, is difficult. They are tiny, tiny insects. Yes, they make webbing but that matches their size. Finding them before they have caused lots of damage takes careful looking, that is for sure.

It is almost like staring at a little spot and waiting to see some movement. It sounds like you have been patient and done that.

The first thing I'd do is take a hose and spray the tiny critters off - as best as I could. If some rosemary leaves fly off, that's fine. They were obviously not very well attached or doing the plant any good.

I would use an insecticidal soap spray on a plant that I much value. I will use dish soap on sunflowers and that sort of thing but dish soap is for cleaning dishes and you have to be concerned about what it might do to the plant. I use Palmolive Green - mostly, just because I've used it so many times before. There may be better choices.

Here is some information on using soap on garden plants [url=https://www.ext.colostate.edu/pubs/insect/05547.html]from Colorado State University (link).[/url] Notice their cautions about damage. I will spray in the late afternoon and like to return the next morning to rinse the plants.

CSU recommends 2 to 3 percent dilution with water and Table 1 gives you the amounts. I use 3 Tablespoons per gallon.

What I do is:

Wash the plants - strongly - with water. Wait for them to dry then spray with the soap mix. Later, rinse the plants.

I hope that this is of some help.

Steve

Louise S
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Thanks for the advice, Steve!

I tried out the homemade pesticide on the plant and can't find anymore mites, but it hasn't perked up at all, so perhaps a soap spray would do the trick.

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applestar
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Be careful not to stress an already ailing plant.

Is your rosemary in a container or in the ground?
It may be that you are not watering enough or watering too much.

Rosemary is drought tolerant because it sends out long deep roots in search of water. In a container, they can quickly become root bound and need frequent watering. Try hefting the pot, if it feels light, it needs more water.

On the other hand, rosemary can get root rot in heavy waterlogged soil or if you let the container sit in drip tray of water.

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rainbowgardener
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Yeah with rosemary it is a bit tricky. Spider mites thrive on heat and dryness. For many house plants all you need to do is keep them moist enough and you won't have spider mites. But rosemary also thrives on heat and dryness and definitely doesn't like to stay too wet.

But one thing I discovered about bringing rosemary indoors for the winter is that it likes to get its moisture more through the foliage than the roots. It likes its soil to stay pretty dry, but it likes the foliage to be misted a lot. Misting it a lot should help keep the spider mites down too (once you have washed them all off to start with).

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digitS'
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I should go back and edit my post . . .

Obviously, spider mites are not "insects." They are Arachnids.

I think they are too lazy to hunt for bugs. They just lay around, sucking plant juices, like so many tourists under umbrellas on the beach. Yes, they like hot dry days and seem to reproduce at an insane rate!

Steve

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applestar
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I WAS going to let you slide on that one... :lol: :wink:

Louise S
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Hello all! Thanks for your comments, they've been very helpful. :D

Seems I might be watering my rosemary a bit too often. It's still not looking too great... For now, I'll just place it where direct sunlight is available and hope for the best!

(nice analogy regarding the spider mites, by the way)

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rainbowgardener
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Yes, for keeping rosemary indoors, it should be watered rarely, but misted in between.



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