Whiteflies

[gars]

I am hoping someone here can help me get ahead of a very pervasive problem this coming year.

My number one problem is whiteflies. I have tried sticky traps, decoy plants like eggplant, Safer Soap, homemade spray of cayenne, garlic, and a touch of cooking oil.... all to miniscule success.

One of the things I intend to do this year is plant Mexican Marigolds and Basil as companion plants.

Has anyone had success against these nasty little moths?

Gary in Marietta GA

[Grub]

I spray pyrethrum, but it might be too harsh for you.
It works if you do it weekly, with a fine mister.
You have to combat them quickly as they spread like wild fire.
Good luck.

[Rena]

Many ways you can head this off.
1. When you overwinter plants from outside you need to keep them far away from your seedlings. Any shrubs that may be infected or you have seen whiteflies on need to be sprayed. I have used neem oil.
2. Many infestations come from greenhouse plants (store bought) I will say over 50% of the plants in the store have them. I always turn over leaves when I am shopping for plants.
3. Keep your plants healthy. I have noticed that they seem to attack the weak plants first. Make sure you are giving your plants enough fertilizer.
4. Inspect your plants often. Don't wait until you see a cloud of dust come out from under the leaves. Whiteflies tend to like new growth. (imo) Really check them out on a regular basis, turning over the leaves and looking for trouble.
Edited to add, any recycle of pots from last year must be sterile and so should the soil. Pests can lurk in pots.

[cosmicgardener]

I plant parsley, dill and fennel - in pots in the greenhouse and outside in the rows. This doesn't kill the whitefly but it is an attractant to hoverflies and lacewings which do kill whitefly ( and aphis). In fact any of the umbelliforous(sp?) herbs and even flowers like queen anne's lace, candytuft, yarrow angelica, letting carrots and broccoli seed will provide homes and breeding conditions for the friendly predatory insects. I am always reluctant to use a broad spray like pyrethrum as it will kill the natural predators, but if it becomes a problem that would be my choice. I also leave little saucers of vinegar in the greenhouse as whitefly will be attracted and drown in them.

[gars]

Thanks for the quick responses. We have tried Neem and Pyrethum. It makes a dent in the population, but only for a few days. The problem is extremely severe here in North Georgia. I had only considered repellent plants like Mexican Marigold. I had tried decoy plants. I had not considered companion planting plants that would attract predotors to the whiteflies. Thanks.

I "seemed" to have some success late last season when I introduced daddy longlegs (harvestmen) to my tomato crop.

I know Darrel Jones of Selectedplants swears common house spiders control whiteflies for him.

[fenneltop]

Gary,
One thing you might consider is easing up on the Nitrogen and making sure the potassium levels are up. K helps build strong tissue in the plant. N builds softer tissue that aphids and whitefly love. I always suggest a good soil test.

Marl

[Rena]

Originally Posted by fenneltop

Gary,
One thing you might consider is easing up on the Nitrogen and making sure the potassium levels are up. K helps build strong tissue in the plant. N builds softer tissue that aphids and whitefly love. I always suggest a good soil test.

Marl

That is interesting! I am going to make sure my greenhouse tomatoes get a little extra Potassium! I knew there was a correlation there. Great advice.

[gars]

Actually, I do have high P-K and lower N.
I use leaf-mulch and composted manure to winter my tomato bed along with kitchen compost. My foliar spray is manure and banana tea with epsom salts, molasses and powdered milk added.

I will do a soil test this spring, as you suggest.

Gary in Marietta, GA

[Ruth_10]

Gary, do the whiteflies damage/kill the plants or do the plants continue on in spite of the whiteflies? I usually see some whiteflies in the spring when the plants are still young, but the plants seem to shrug them off as they grow and mature.

[BigdaddyJ]

Here's your solution. I just posted thisd to the person with the spidermite problem but greenlacewing nymphs will eat ANY sucking insect in their path. They are usually used to control whitefly, aphids or mites.

Whiteflies are easily contolled by green lacewings. Buy or order some and release them at the earliest onset of infestation and be prepared to say goodbye to your pests in a couple weeks.

Totally organic. Totally natural. And best of all totally easy to apply...

Throw away all those messy and inefective (long term anyway) sprays and enjoy nature working in harmony and letting you free to enjoy your tomatoes.

[gars]

In answer to Ruth 10: We have actually had sufficient weakening of some plants (Gregoris Altai) to eventually kill them, yes. I have never seen the huge influx we have around here.

In answer to Bigdaddyj: I did introduce green lacewings last year. They didn't hang around very long though. How do you keep them happy in a outside garden? Same issue with other beneficials. I couldn't keep them around the garden very long. I left some bee pollen in the area, having read that will feed adult lacewings, who do not eat other insects, but I couldn't see that it helped. I would vastly prefer natural remedies. Thanks, gary in Marietta GA

[BigdaddyJ]

gars, I order the lacewing eggs every year. They are about $12. Some have already hatched by the time they arrive. I wet the foliage and sprinkle a little here and a little there. We grow many flowers here as well and I do see the adults hanging around but they do not overwinter here in Delaware. I used to have a huge spidermite problem but not anymore. I haven't seen a single mite the past 4 or 5 years. I will see a few whitefly very late in the season but their numbers are tiny versus what they were like before I went with the annual lacewing release. Too few to do any damage whatsoever. The lacewing larva work here and work very well. I see the adults mostly on the dill and cosmos but sometimes on zinnias.

[cosmicgardener]

I mentioned this in an earlier post - I plant annual herbs and flowers to attract, feed and help colonise certain insects. Lacewings love Dill, Fennel, Alyssium, Angelica ( esp good) Cosmos, Queen Anne's Lace, Tansy. I suggest plant around the tomatoes and around the greenhouse so that flowers are there before you introduce lacewings as they will go off looking for somewhere to feed and live if you don;t provide it. These flowers will attract hoverflies too. I'll add zinnias to my list!

[gars]

To BigdaddyJ : I ordered my Lacewings from ARBICO last year. Do you have another supplier you prefer. ARBICO sent eggcards I attatched near the infected plants.

TO cosmicgardener: As I stated earlier I will be doing more companion planting this year, and you can be sure I have printed your suggestions for reference and use - In fact, this entire thread is going into my garden journal.

Gary in Marietta GA

[BigdaddyJ]

gars, I have always ordered from Garden's Alive. With their 50% off sales they are reasonably priced. I can time my eggs to arrive at the appropriate time which here is early June. There are some aphids here that keep the larva busy until the whiteflies show up. Sucking insects are no longer a problem for me.

The eggs come mixed in food for the ones who hatch during transit. I just sprinkle all over the garden trying to space them evenly. The foliage should be wet. Late afternoon is best.