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Has anyone in Chicago proper has difficulties with whiteflies? I didnt' have any the first year I set up the containers, but the past 3-4 years they have been brutal. I typically only have a few tomatoes, a couple of peppers, some herbs and some flowers. The tomatoes are hardest hit each year.

If you have them, what have you tried to get rid of them and how has it affected your yield? I've used high-power water spray, soap, yellow sticky mats, and once in a last ditch attempt to control them, some chemical. None of these really controlled them and over the summer I steadily lose plant foliage and fruit.

white flies come in from where you get your seedlings. they can't live in the winter around here. you probably wont have them this year. maybe try a different supplier.

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i used to milk cows

That's what I thought, too, teatpuller. Thanks for your knowledge; it's validating my theory.

The first year they came from items I bought at Gethsemene. So, the next year, I started my own.

Guess what? Yep, whiteflies.

Last year I tried Meinkes. Same problem. As much as I love having fresh tomatoes, peppers, etc., I am about to give up. I am guessing that one of my neighbors buys things from someplace and their plants have them. I'm in a large-ish condo building and our decks on the top floor are all connected. The whiteflies wouldn't have far to go to find my tomato, pepper, or other plants.

Since I'm originally from a country area and have gardened a bit over the years (always growing my own from seeds), I've never had whiteflies before. I was wondering if the proximity of gardens here in the city created problems such as this for anyone else.

Hi View Askew,

I had huge problems with whiteflies and aphids for a couple of summers with my tomato plants in pots when I first started gardening.

For the last two summers, I've been using "good" bugs to kill the bad bugs. I bought lady bugs very early in the season and released them. Lady Bugs love to eat whiteflies and aphids. About a month later, I bought a praying mantis egg sac and hung it on one of the stakes I used to prop up my tomatoes. The egg hatched and also went to work on eating my bad bugs.

I've also planted basil in the same pot as the tomatoes last summer. From what I've read, the jury is mixed on whether the chemicals in basil repel whitefiles, but if you have the space and like basil, I see no harm in trying this method.

Kim

Funny you said that, Kim, I used to do that when I had a large garden and lived on 3 acres. I just wasn't sure it would do me any good on a rooftop garden that is just 4 Earthboxes. I thought they'd just fly away, looking for more food sources. Maybe I should try it.

I do grow basil right next door to the tomatoes in the next earthbox, but not in the same one. Since I have limited space, I tend to put two tomatoes together in one box, then one box with assorted herbs - thyme, oregano, basil, mint, etc., than one or two more boxes - one with more tomatoes maybe, and another with peppers or beans. All of them are within a few feet of each other. I don't know if that is close enough. Maybe I should move things around this year so that the basil is on either side of each tomato and only put one tomato in each box.

I have a book on what to grow to repel things, but didn't think to look at it.

Considering the number of whitefly larvae I have seen on the undersides of Genovese basil leaves, I am very skeptical concerning basil's purported ability to repel whiteflies.

Whiteflies can be carried on the wind for substantial distances, so starting with clean plants is not enough.

That's the most logical to me - that they are not coming from me, but from neighbor's. So, then, controlling them is the only solution if I am to continue to grow on my deck.

They make gardening a chore for me. I spent years gardening and never felt like it was work. I had other pests, but not like these, and I always had a reasonable solution. It seems that none of the solutions I've tried are all that effective.

ekreider, what have you done to control them? And, has it worked?

1. You won't get them all no matter what so try for a tolerable level a la integrated pest management's economic damage criterion.

2. Yellow sticky cards will get some whiteflies but are more useful for monitoring infestation level, particularly the arrival of the first ones. The sticky cards will show the start of infestation before the pests become really obvious. In addition killing a few of the early ones is like swatting early flies before they have time for exponential proliferation.

3. Beneficial predatory insects can help kill some larvae but won't do a major part of the control job. Green lacewings and parasitic wasps (no stingers) are probably the most effective but are pretty mobile as adults. The praying mantis looks pretty neat but seems to be territorial enough to guarantee that they will not do a major insect control job. In any case most of the beneficials prefer aphids to whiteflies. If your neighbors have bought plants with whiteflies, there is a good chance they also bought some aphids.

4. Insecticidal soap spray is fairly effective on larvae but must contact them to be effective. Once infestation occurs, there will be more hatching every day. Spraying is needed every five to seven days. Soap sort of works on the adults if you get direct hits on their bodies. Good luck on doing that.

5. Other organic sprays such pyrethrum (from pyrethrum daisy petals) and rotenone (from a tropical root) will kill the larvae and adults on contact but also kill beneficial insects including pollinators. If you have to resort to these, spray near dusk to minimize contact with pollinating insects such as bees. Using more potent or persistent insecticides such as malathion or carbamate just increases side effects without killing many more whiteflies.

6. Systemic insecticides that make plant juices toxic work pretty well but should be used only on ornamentals for obvious reasons. If you have infected ornamentals such as fuchsia or coleus, use a systemic on them to help confine the problem.

7. Growing your own plants from seed as I do helps delay infestation. The whiteflies will come from neighbors even if you live in a neighborhood of single-family houses as I do.

Thanks ever so much. That is a very comprehensive list.

It's too late for me to start my own tomato plants this year, though that's all I used to do when I had a large garden. I'll go back to that next year. This year I may just take a break from tomatoes and try something else.