One of my favorites, sunflower, is a good companion plant for corn and tomatoes. Native Americans grew it with corn before Europeans colonized America. It is said to increase corn production, and it certainly traps aphids, keeping them away from corn. Tansy is beneficial to cucumbers, squash, raspberries, fruit trees, peppers, corn, and roses. It either repels or distracts certain pests such as Japanese beetles, cucumber beetles, squash bugs, and sugar ants. (A distractor plant keeps the undesirable bugs to itself so that the bugs don't wander to any other plant.) Even though my mother gave me tea with tansy in it, it can be toxic to livestock, so don't plant tansy near where livestock browse. In addition, don't plant it near collard greens; those two plants are not happy near each other. My mother also put yarrow in my tea, and probably not because of Peter Yarrow of Peter, Paul, and Mary fame. It is said to be beneficial to many plants, and it attracts ladybugs as well as damselbugs and hoverflies all insects you really want in your garden. If you are growing any herbs for their essential oils, plant yarrow nearby, as it may increase essential oil production. It's great for enriching compost and so, of course, as mulch. Our last companion flower, nasturtium, is a friend to many plants, including melons, cucumber, squash, beans, tomatoes, broccoli, cabbage, radish, and apple trees. It is said to be just about the best plant there is for attracting predatory bugs, which is a wonderful thing, because they eat all those awful bugs we don't like, especially aphids. Those are exactly the bugs that nasturtium either attracts to keep them away from its friends or repels, for the same purpose. So keep in mind that you are not the only one who does well with your friends; some flowers help each other, too!
Give Your Flowers Some Companions, Part 2
There are just too many flowers that help other plants companion plants, we call them. Either that, or these columns are too short. In any case, I find myself compelled to write about some more helpful flowers that are wonderful companions to their friends. Those who love asparagus should grow petunias nearby. This delightful flower also benefits squash, pumpkins, cucumbers, beans, and potatoes. It traps leafhoppers just as geraniums do, and it repels Japanese beetles and aphids as well. However, do not plant it near an apricot tree; the two plants are not friends.