On this site using a there is a helpful hint instructing you to use a shop-vac to suck up whiteflies. It is followed by note of caution about the possibility of sucking up plants and plant parts. I liked the shop-vac idea, it worked well, but I put my own twist on it so I could better protect my plants if there was an unexpected encounter with the business end of the shop-vac’s hose. With a little preparation, you can actually vacuum your plants, allowing for removal of such pests as whiteflies, spider mites, and others, without causing extensive damage. Here’s what you do…
Take an old shop-vac hose and punch numerous small (1/8" to 1/4") holes in it approximately 6 inches from the working end. The number is not exact and needs to be tinkered with. This serves to reduce intake velocity and also lower the vacuum level when intake air is impeded like by leaves. The result is that you can vacuum your leaves without extensive damage. The “fluttering” of the leaves in the intake of the hose serves to dislodge mites and eggs alike (and remove webbing). Different plant species have different tolerances to this, so personal experimentation is needed. However, losing some leaf tips to the vacuum is far less damaging than a full infestation of mites.
Depending on the specific leaf and stem structure of the plant, I have even used the larger diameter hose to literally stick over an entire stem to suck the little demons away. While this is not a solution to the infestation, it can serve to lower pest levels and even to buy some time while you wait for biocontrols to arrive. Obviously, you would not want to do this after biocontrols have been deployed, but I make a habit of doing this just prior to release of biocontrols.
One important thing to remember is that whatever pests you suck up are probably still alive in the storage tank. Once you turn off the vacuum, they are free to find their way out again and even to breed inside. After vacuuming the plants, make sure to empty the shop-vac far far away from your garden/greenhouse. I then spray down the inside of the plastic tank with peroxide or bleach mix to kill off anything left inside.
About the author: Randy Steele is an organic vegetable gardener and full-time nursing student who resides in the “sticks” of Maine.
Mike Cherim responds:
Posted: October 14th, 2007 at 11:42 am →
Thanks for contributing, Randy. This is an excellent idea indeed.