Marigold care: French, African, signet
Marigolds are among the five most commonly grown annuals in North American gardens, and also among the most frequently misrepresented in terms of pest management. The claims about what marigolds repel range from well-documented to folklore. This guide covers what is known, what isn't, and how to.
Marigolds are among the five most commonly grown annuals in North American gardens, and also among the most frequently misrepresented in terms of pest management. The claims about what marigolds repel range from well-documented to folklore. This guide covers what is known, what isn't, and how to grow all three main types well.
The three types — French (Tagetes patula), African (T. erecta), and signet (T. tenuifolia) — are all easy to grow but differ meaningfully in size, flower form, heat tolerance, and the conditions under which they perform best.
Species overview
Per Missouri Botanical Garden:
- **French marigold (Tagetes patula)**: 6–18 inches tall; single or double flowers 1–2 inches across; blooms from early summer to frost; the most widely used in vegetable garden companion planting
- **African (American) marigold (T. erecta)**: 18–36 inches; large double flowers 2–4 inches across; less branching; requires deadheading; less cold-tolerant than French
- **Signet marigold (T. tenuifolia)**: 8–12 inches; small single flowers; ferny, strongly aromatic foliage; edible flowers; excellent heat tolerance; reseeds freely