Studies have proven that the Mexican marigold actually fights some ground weeds such as the elder, bindweed and couchgrass. They also can fight off nematodes and worms that eat away your beautiful plants! Marigolds are said to be good companion plants or cover crops. The African Marigold and the French Marigold also fight harmful nematodes.
Marigolds are a natural insect repellant as well. Insects avoid marigolds because of the pungent odor that the Marigolds emit. This is also why marigolds are used largely as an outside flower as opposed to inside. You can also make an insect repellant tonic with Marigold leaves. Simply liquefy the stems and leaves of the plant in your blender, let it soak for a day then add water to dilute and apply as needed.
Plant your Marigolds after the last frost of the season and they will bloom into the autumn months in warm temperatures. Marigolds excellent for planting close to your vegetable garden or just mixed into your flower garden. They should be planted where they can get full to partial sun with rich soil. Once established, marigolds require little care. They are hardy plants that come in a variety of colors to suit your liking.
Insects that will bother your Marigolds are spider mites, spittle bugs, aster yellows and wilt. Keep these insects at bay and your beautiful Marigolds will survive all season! Marigold varieties vary from 6 inches to 4 feet in height. Consult your local nursery or landscape specialist to see what variety will work for your garden needs.