Hand-Picking the Bugs Out

by Kevin
(UK)

I'm attempting to grow specimen roses and I'm not doing too badly as it happens - thanks to your good advice here. However, during my regular checks I have noticed some very tiny white bugs. You could fit maybe 3 end-to-end to 1mm. You can't see their legs although you can see them move.

Now, where I saw a little grouping of more than 6 of them, I simply took the whole leaf off. I guessed they might have been breeding on the underside of the leaf with eggs I cannot see, so off the leaf came.

Where there were only one or two bugs I squashed them between my fingers without stress to the leaf. But there were some bugs that I couldn't get to so easily; between the main leaf vein (what's that called?) and the leaf itself. I don't want to use the detergent and fat bug killer, as that really seems to make the plants suffer; it takes them some time to recover.

So do you have any ideas how I can thoroughly hand-pick/clean each leaf safely. I thought about a wide artists brush sprayed with something or a pressurized water sprayer, but I don't know how the stomata will cope with such an assault.

My filters are good - I think the bugs have come in through the compost, which was cheap but came in first in an independent trial. Any thoughts, please, J?

Answer: Kevin- good to hear from you again. The key to battling garden pest successfully is proper identification. I learned this the hard way. After four weeks of treating some garden plants with neem oil, thinking I was up against a mite infestation, I finally purchased a 30X magnifying scope (relatively cheap) and was able to identify the pests as thrips. Turns out neem works on many pests, but not on thrips. My plants had already experienced quite a bit of damage by that point, from all the sap-sucking thrips as well as from the neem treatments (which tend to clog some of the stomata).

I tried to research your pest, using the "1mm" estimate and description as being "white". Unfortunately, I wasn't able to pin down any possible identification without actually seeing the bugs myself. My gut feeling is that you probably have thrips, but you MUST identify them positively before you proceed. The bad news is that thrips can be just as difficult to get rid of as mites (nearly impossible without shutting down the whole grow room and starting fresh).

Hopefully, this is not the case. Picking off individual leaves may remove larger groups of the bugs, but chances are they are already over much of the plant. Plus, you really don't want to be pulling too many leaves from your plant---if you can't get rid of the bugs, the leaf pulling will never stop!

Once you have a proper ID, it will be much easier finding out what will be most effective against your particular pest. Diatomaceous earth, SM-90, and "Bang!" are are all non-toxic, non-systemic, organic pest control options. They are all very easy on plants, and could be used to keep the problem in check until you can figure out a more permanent solution (after you ID).

Another very promising product using silver nano-particles and essential plant oils has just come to may attention recently. You can read all about in this post here if you are interested. Apparently the silver nano-particles make the essential oils much more effective. If is works as well as the indications I am getting suggest, it could be an effective new weapon against spider mites, powdery mildew, and a laundry list of other pests.

Just one final suggestion before I leave you. At least for mites, the grow room temperature is critical to controlling them. At 70 degrees, they do not reproduce fast enough and are manageable. But at 80 degrees, they multiply fast, establish fast, and are nearly impossible to keep in check. It's possible your current pest would respond in a similar fashion, and keeping your grow room temp in check (if it isn't already) may give you the upper hand in this battle.

Hope all works out well Kev, and Happy Growing!