ASTERACEAE, The Aster family
I grew these ‘French Vanilla’ hybrid marigolds from seed and find them quite pretty. Otherwise they are rather useless. The stems are too short to make them good for cutting, and if any water gets on the blooms they discolor and rot. (Luckily it rarely rains in the summer in Portland.)
Beneficial insects prefer plants with single flowers so they can get to the pollen or nectar with out too much fuss. While these flowers are insanely double, they can still repel pathogenic nematodes with their roots, and perhaps ward off rodents with the smell of their flowers and leaves. They smell like marigolds, but not strongly and according to the seed packet (Odorless!) that is a virtue of their hybrid nature. And another thing, aren’t marigolds supposed to be..gold?
One of the charms of marigolds is that they are very easy to grow from seed. My junior high science fair project involved measuring the germination rate of seeds in various media, using marigolds as a subject. Their seedlings come up quickly, are very sturdy and transplant easily.
When I was little my mom planted a thick band of short orange marigolds around our organic vegetable garden from seeds she had saved from the previous year. After my parents divorced my dad kept planting the garden each year, but didn’t include many flowers. When I started helping him again we had such a terrible problem with squash vine borers, potato beetles and grey aphids. We thought of the marigolds and decided to try planting them as an insectary for beneficials/repellant. The next year and each season since I planted several flats of marigold starts throughout the garden, and the insect problem has subsided.