Marigold

French marigold is a compact annual grown for steady flowering from early summer to frost in yellow, orange and mahogany. It is the standard edging and container plant, 6 to 24 inches depending on the type, and it is planted through vegetable gardens because its roots release compounds that suppress some root-knot nematodes in the soil.

It is a warm-season annual with no frost tolerance. Sow indoors six weeks before last frost or directly once the soil has warmed; it germinates in days and flowers within eight weeks of sowing. Full sun and average soil are all it asks, and it tolerates heat and poor ground better than most bedding plants. Deadhead to keep it flowering, and water at the base, since wet petals rot.

The single and semi-double types feed bees and hoverflies; the fully double ones offer less. The scent that people either love or hate is what keeps deer and rabbits off. Slugs are the main pest of young plants. Save seed from the best plants at the end of the season; it comes roughly true from open-pollinated strains.