vstolb
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Joined: Wed Feb 01, 2012 4:24 pm

What's wrong with my rosemary?

It's been like that for a while... with weird white spots... smells great though and not dying. I cut off a small branch to take a close up pic. The whole plant is like this. There are a lot of grayish small bugs on the under side of the leaves but I couldn't snap a good picture of them... How do I fix this? This rosemary is my only plant right now so I want it to get well again :)
[img]https://oi48.tinypic.com/ay61jm.jpg[/img]

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applestar
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Location: Zone 6, NJ (3/M)4/E ~ 10/M(11/B)

Yep the white spots are from sucking insects piecing and sucking up the juices from the leaves -- presumably those "grey bugs"

Is this plant in a container? If so, take it to a sink , lay it down sideways and, with faucet spray attachment or use a handheld sprayer adjusted to spray spurts rather than mist (or use a garden hose attachment outdoors), and spray from under the leaves to dislodge as much of the bugs as possible.

This is best done when the plant is ready to be watered.

If the bugs are very difficult to dislodge, after wetting the foliage, you can spray with dilute soapy water. Soap not (dish) detergent. Wait 5 minutes then rinse off thoroughly with plain water.

You will need to repeat next time the plant needs water, and probably at least one or two times more to break the insects breeding cycle.

If you can, try taking a photo of the bugs. Let's see what they are.

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ElizabethB
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Location: Lafayette, LA

Definitely a piercing/sucking insect. If the rinsing and soap solution does not get rid of the buggers a light summer insecticidle oil will work. You just won't be able to harvest your rosemeary for a couple of weeks and will have to wash well before using. Try the water/soap trick first and see if that works. Insecticidal soap or summer oil would be a last ditch effort to save the plant if nothing else works.

LOL

imafan26
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Location: Hawaii, zone 12a 587 ft elev.

Most herbs are hard to treat since they are not listed on most pesticide labels. Thrips, and aphids are the most common sucking insects and thankfully they are the easiest to kill. However, treatment will have to be repeated often because those buggers multiply fast. Does your plant need repotting? Rosemary usually can fend off most attacks when it is not in distress, repotting might help it stay healthier. If the plant can handle it cut it back. Check if other plants nearby are also being attacked consider sanitizing the whole area. :roll:

toboboto
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Joined: Tue Dec 31, 2013 12:33 pm

would neem oil work for a toxin free solution?

imafan26
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Location: Hawaii, zone 12a 587 ft elev.

Neem oil will work. However, even organic products like horticultural oils and soaps have some toxicity. If it was truly non-toxic it would not work very well.

It can be irritating to eyes and skin in sensitive people but it has a low toxicity.

It can be moderately toxic to fish and while it does not harm adult bees it can be harmful to bee larvae if pollen that has been sprayed is taken back to the hive and fed to the larvae.



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