In my experience, like so many other of the companion planting claims that don't hold up to actual practice, yes, they do attract problem insects. Some beneficials too but I can get them to the garden without issuing the invite to the bad guys.

Dave

I can say I had less of a problem with horned and fruitworms when I planted them with my tomatoes.

Marigolds planted in full sun attract spider mites. You may be seeing the benificials eating the mites. Here is one of several links showing how Marigold's attract spider mites. I also have first hand experience! It's not pretty...

http://aggie-horticulture.tamu.edu/PLANTANSWERS/fallgarden/nematode.html

That's a good question! I have always heard to plant marigolds around garden, and figured there had to be some benefit to it. For the past two years I have planted them, and not sure, but I think they do help, even if they are just bait plants. They do have a strong odor, which would confuse the pests that seek out plants by smell, right?

In 2008, I had tomato hornworms. I sprayed and then had to constantly remind my kids not to eat the fruit until I could wash it. My kids don't listen...

In 2009, in an attempt at organic pest control, I planted all kinds of flowers and basil in the tomatoes. I didn't have ANY pests, including hornworms. My tomato plants grew SO big, there wasn't much sun for the poor flowers, and the basil sulked, but I believe they did their expected jobs.

I tried Marigolds last year. They were covered in spider mites, which had never been a problem before that. Once they were done with the Marigolds, they moved onto the tomatoes, so as a trap crop, they did a terrible job.

The only thing I could do to combat them was to hose them down with high pressure water at least every third day. I had to do the same with the tomatoes. This did a pretty good job of knocking them off the plants, making the mites start back over. When I did this, they worked as a trap crop because the marigolds stayed alive. I had 50 tomato plants last year with Marigolds dispersed among them. Needless to say, my water bill sucked!

I'm not growing Marigolds in my back yard this year (where to tomatoes are). I did plant them in my front yard, however. The hope is that they will attract beneficial to the front yard that might make their way to the back yard.

Does it matter what kind of marigolds you plant? I'm completely smitten with the lemon (and tangerine) signet marigolds. Not so much for their flowers (pretty but tiny), but the scent of their foliage. Supposedly, the scent deters mosquitoes. Can't say for sure if it works, but it really is a pleasure to walk by and "fluff" them with my fingers to get a scent of the foliage. IÂve never noticed any insect activity around them. Maybe I wasn't paying attention? Long story short, I started a complete flat to interplant in my beds.

Something else to consider is that your mileage may vary based on location. I've noticed that the people here that have had good luck with marigolds tend to live in cooler climates. Colorado and Massachusetts have a much different climate than Texas and Arizona.

My only problem with marigolds was the spider mites and they didn't really become a problem until things really heated up. We had nearly 100 days of 100 degree temps last year. Since mites love heat, that probably has a lot to do with it.

Meb504 is listed as Central Texas, as am I, so I would recommend against planting them around tomatoes, but they do well elsewhere as long as you hose them off from time to time.

susan2010 hit nail the the head the type marigold does matter. the only marigold that are useful in this matter are french and Mexican marigolds. any other type marigold does not work for more info on the pests that these two types marigold get copy Of" Carrots love tomatoes".

archerb, same here. I never had spider mites infest my tomatoes until I planted those %@!# marigolds! And I'm talking infestation of biblical proportions! I did some research and sure enough there is a lot of evidence they actually attract spider mites in full sun and it doesn't matter what type of mariglods either. French, Japanese, Lower Slobovian...the mites aren't prejudiced. At least the mites were easy to get rid of in future years...just deep six the marigolds!

AHHH -

I plant French and Pot Marigolds or Calendula. I'm a fan of the reseeding flowers - "lazy" gardening is awesome!!

I never noticed bugs either, but my marigolds weren't in full sun very long. By June, the tomato plants blocked the sun.

bigdaddyj there 6 basic types marigolds the common type Tagetes do not have any pest deterring properties as stated before.
Also the marigolds that do deter pest only deter certain
pests; not all pests. So before planting a plant for pest deterring properties you know what pest it deters and any it might attract.

Doing at bit research before going on rant will save time and you might actually learn something. And not look like you are clueless on an interesting subject.

Aside from the marigold issue, you really should learn who your friends and enemies are -- get an insect recognition book such as the excellent "Good Bug, Bad Bug." Maybe all the insects you see are beneficial!

Please! There is so much evidence that marigolds attract spidermites that by not accepting this as fact is like denying the world is round. A simple google will show you all you need to learn this. Start with the link I provided above and then read the next 500 or so. I never mentioned anything about detering any pest! I only mentioned they ATTRACT spider mites.

So sorry but I have to strongly AGREE with bigdaddy on this particular "companion planting" ploy. Marigolds attract spidermites (aphids too) regardless of the type of marigold and neither pest is beneficial to the garden. "Doing a bit of research..." in something other than the various companion planting bibles quickly proves that point.

Please understand that companion planting as it is preached and practiced by some is considered by many experienced gardeners to be nothing more than a gardening fad. Its advocate's books are filled with logical fallacies and invalid assumptions, claims that cannot be proven or replicated, and regional old wives tales.

Yet every few years it seems a few new gardeners suddenly discover one of the books and buy into its message whole hog. Despite little practical experience, they too begin to preach its benefits and we have a cycle of "just plant _______ with it to solve that problem" companion planting posts throughout the forums. It's the reason why Spike created their own forum for them years back.

They never seem to realize that most of its claims have been around for eons and that while some may work, many are just coincidence and happenstance. Many have been tried and tested by experienced gardeners, horticulturists, and the scientific community, and for the most part once the variable of coincidence is controlled for, they never stand up to actual testing.

So if you like the color and smell of marigolds then by all means plant them. But don't grant them mystical powers of pest control - please.

Dave

Happy Gardening All!!

Sharing info is wonderful.

I, (an analytical chemist before kids) for one, will plant flowers near my tomatoes until I find another hornworm or other destructive pest that the flowers actually attracted.

I didn't see a single destructive pest last year, so here's to hoping coincidence repeats in 2010 my garden.

Since I have kids that enjoy eating the tomatoes in the garden, I refuse to spray. This mom is clinging to the fad.

Peace

Here's an interesting link on the subject. Seems they have benefits ... but only to a certain kind of pest, and only when planted a certain kind of way.

Here is a link that might be useful: Marigolds

Last year was the first year I did not plant any marigolds. My garden was INFESTED with cucumber beetles of biblical proportions. Coincidence? I'm planting marigolds this year.

Interplanting so that something that produces lots of tiny, open flowers (letting some of your herbs go to flower, yarrow, alyssum, etc.) is always blooming does wonders to attract parasitoids and predators of sucking insects and of many caterpillars. You can see the air around your beds full of hoverflies, etc. when you plant these, and with them are many less noticeable predators and parasitoids. Almost all of the larger caterpillars I found were parasitized, and the few aphids I did find were mostly parasitized.

But I have marigolds in my ornamental beds, and they just seem to attract pest bugs without attracting much in the way of predators.

Yes, they have been on my marigold but they have not touched my tomatoes and peppers - very, very few. However, before they drop to the ground to become grubs, I go around with a small bucket with oil on the bottom and knock them in there. Once they are coated with oil, they can't fly out. I have very few pest in my tomato and pepper garden.