Good info and commonly discussed on the Companion Planting forum here. Be sure to check it out.

Dave

Here is a link that might be useful: Companion Planting Forum

I tried marigolds all around the vegetable garden one year. They attracted every spidermite for miles. No thanx. Once bitten and all that...

This is kind of old news. I plant them each year, but I am not convinced that they do much except provide some nice cheerful color. My crookneck squash was just killed by squash beetles, so so much for that.

Folklore is wonderful, isn't it?

I planted radish and oregano for companions to my cucurbits. The acorn squash was just taken by SVB. The cukes seem to be doing alright, but I'm not sure I don't have some virus starting. They've always wilted in the heat of the day, but lots of leaves starting to yellow. Production still seems good.

I planted basil as companions to all my toms, haven't seen a horn worm (yet).

I have a nice patch of marigolds right next to my squash (within 3 feet) and the squash bugs were worse this year than I've ever seen them. So, maybe there would have been thousands more without the marigolds, who knows. I plant them more for their beauty than their repellant qualities anyway.

Sandy

maybe not all mairgolds are equal.

This is the first year I've done companion planting and it's working well for me. I have French marigolds, Calendula, Love in a Mist (accidentally) and Borage.

Past years, I've had tomato hornworms and this year NONE - knocking on wood.

Based on what I had read, I expected more beneficial insects, but do not see as many as I thought I would.

Perhaps it's coincidence but I am happy with the whatever the flowers have done for my tomato patch.

I know for sure the pretty flower blooms keep my toddler occupied so she picks fewer of the green tomatoes.

My sister tried it, and the deer raced the rabbits to the marigold plants.

One reason it sorta-kinda works is that syrphid fly adults (hover flies) like the pollen and nectar and lay eggs on the surrounding plants. Their larvae look like a micro-Jabba the Hutt and devour any bug they can catch.