How to grow marigold
Overview
Marigold (Tagetes patula) is a fast-growing, warm-season annual grown for its bright, long-lasting flowers and pest-repelling foliage. It fills gaps in borders and veggie beds, blooming from spring through autumn in warm weather.
Varieties
- French Marigold 'Bonanza' — Compact, 25 cm tall, large double flowers in orange and gold — ideal for borders and pots.
- French Marigold 'Durango' — Early-blooming, 20 cm, bicolour red-and-yellow flowers; heat-tolerant and long-lasting.
- French Marigold 'Janie' — Dwarf, 15 cm, uniform blooms in bright orange — perfect for edging and containers.
Soil Preparation
Marigold prefers slightly acidic to neutral soil (pH 6.0–7.0) with good drainage. Work in well-rotted compost or aged manure before planting. Avoid heavy clay; if soil is poor, add sand or grow in raised beds.
Growing Guide
Sow seed 6 mm deep in seed-raising mix or direct in garden beds after frost risk passes. Space plants 20–30 cm apart. Marigold needs full sun and well-drained soil; water at the base to keep leaves dry. Pinch out tips when 10 cm tall to encourage bushy growth. It is a short-lived annual, so succession-sow every 3–4 weeks for continuous colour.
Sowing
Sow seeds 6 mm deep, 5–10 cm apart, in seed-raising mix or directly in garden beds. Germinates in 5–7 days at 20–25°C. Can be started in punnets and transplanted after 3–4 weeks when 10 cm tall.
Care
Feed every 2–3 weeks with a balanced liquid fertiliser (e.g., seaweed or fish emulsion) during active growth. Deadhead spent flowers to prevent seed set and extend bloom. Cut back leggy stems by one-third in midsummer to rejuvenate.
Companion Planting
Plant marigold near tomatoes, brassicas, beans, and cucumbers to repel aphids and whiteflies. Avoid planting near fennel or dill, which may attract pests that also target marigold.
Common Pests & Risks
Aphids cluster on new growth; blast off with water or use insecticidal soap. Slugs and snails eat young seedlings at night; scatter iron-based pellets or crushed eggshells. Spider mites appear in dry heat; mist foliage and improve air flow.
Harvesting
Harvest flowers for cutting when petals are fully open but before they begin to wilt. Pick in the cool of the morning for longest vase life. Regular deadheading every few days keeps plants blooming.
Troubleshooting
Yellow lower leaves: overwatering or poor drainage — let soil dry out. Stunted growth: root-knot nematodes — plant in clean soil or use marigold as a biofumigant. Few flowers: too much shade or high nitrogen — move to full sun and reduce feed. Powdery mildew on leaves: poor air flow — space plants wider and water at base.