The marigold flower is known for its prominent smell. It may seem a little musky to humans, but it’s overwhelming and acrid to insects like yellowjackets. French and African marigolds actually produce a chemical called thiophene that contributes to their strong scent and can be purchased as an essential oil to distribute around your living spaces. Additionally, some marigolds release a poisonous chemical from their roots that can fight off nematodes, invasive worms that damages plant root systems. The French marigold is generally considered the most effective for this purpose. Marigolds can repel all sorts of other insects too, like mosquitoes, whiteflies, and aphids, not just yellowjackets. They can even help keep deer and rabbits from nibbling away at your garden goods. Generally, marigolds are not favored by any bees either, as their double-flower configuration makes it challenging to collect pollen (and they contain little pollen anyway).

While there is nothing to say that any specific color will drive yellowjackets away, there is evidence that different kinds of colors elicit different responses. Notably, these wasps are attracted to bright shades and less inclined to associate with darker colors like red and black. Though marigold colors might often be appealing to wasps, their smell is enough to deter the insects. For an amplified effect, consider planting them next to other plants known to suppress wasps, such as red geraniums, mint, eucalyptus, and wormwood.

Source: housedigest.com