Here are a few lines from a place in NZ that I purchase my seeds from.
I am starting to use flowers as companions and insect/bug/grub repelants.
Basil - Basil is best planted next to Tomatoes - everyone knows how well they go together in cooking! Used as a border for the Tomato patch, the plants will find it easier to resist disease & the fruits will be tastier. Bees love Basil, while Aphids, Fruit-Fly, White-Fly, the
House-Fly & Mosquitoes hate it. Keep a pot near doors & windows to keep Flies out of your Home. Also very handy for medicinal & cooking uses if grown nearby. Keep Basil away from Rue - they definitely dislike each other!
Tansy - Tansy is a good all-round bitter Insect repellent. It is great planted near Cabbages, Roses, Raspberries & Grapes. It concentrates Potassium in the soil, so benefits any plants nearby! Plant it for protection against Japanese Beetle, Striped Cucumber Beetle, Squash Bug, Cut Worms, Cabbage Worms,
Ants, Flies, Mosquitoes & Fruit Moth. It is noticeably helpful under Peach Trees, which it assists greatly by warding off flying insects & keeping Borers away.
LINKY