Calendula, or pot marigold, is the sunny, unfussy flower that every Zone 9 garden should have: bright orange and yellow blooms for months, flowers you can use in the kitchen and the medicine cabinet, and a plant that shrugs off poor soil, light frost and neglect. It is one of the easiest flowers to grow from seed, and one of the most useful.
In Zone 9, calendula is a cool-season flower at its best in autumn, winter and spring. Sow it in autumn and it will flower through the mild winter; sow it again in late winter for a spring display.
Zone 9 at a glance
USDA Zone 9 covers the warmest parts of the southern United States, including much of Florida, southern Texas, southern Louisiana, southern Arizona and coastal California. Winters are mild, with average winter lows of 20 to 30°F, and the growing season runs nearly all year.
The average last spring frost is Jan 30–Feb 15 and the average first autumn frost is Dec 1–15 — USDA/NOAA averages, not exact dates, so check your local extension service before planting.
| Detail | Zone 9 guidance |
|---|---|
| Average winter low | 20 to 30°F |
| Average last spring frost | Jan 30–Feb 15 (average/range) |
| Average first autumn frost | Dec 1–15 (average/range) |
| Days to germination | 7–14 days |
| Days to maturity | 45–60 days |
| Sowing | both |
| Sun | full sun |
| Soil pH | 6.0–7.0 |
| Spacing | 9–12 inches |
| Water needs | moderate |
| Cold tolerance | hardy |
When to plant calendula in Zone 9
Sow calendula in Zone 9 in autumn, from September through November, and again in late winter, from January through March, for flowers through the cool months. Seeds germinate in 7–14 days and plants flower in 45–60 days, so a September sowing is blooming by November, and a February sowing flowers by April. The average last spring frost in Zone 9 is Jan 30–Feb 15 and the average first autumn frost is Dec 1–15 — those are USDA zone averages, not exact dates for any one garden, so always check your local extension service for your own frost dates. Calendula is hardy and tolerates light frost, which is why the autumn sowing works so well. Avoid sowing in the heat of June, July and August: the plants will grow, but flowering will be poor and short-lived.
Work back from the frost dates: the planting calendar hub and the September in Zone 9 month guide show what else is happening at planting time.
Starting calendula in Zone 9
Direct-sow calendula where it is to grow, or start it indoors in pots — both work well in Zone 9. Sow seed a quarter of an inch deep in shallow drills, cover lightly, and water gently. Seedlings appear in 7–14 days; thin them to 9–12 inches apart once they are big enough to handle. If you start seed indoors, harden plants off for a week before setting them out, and transplant them when they have two or three true leaves.
See also when to plant calendula in Zone 8 for the same crop in a cooler zone.
Soil, spacing, sun and water
Calendula needs full sun and average, well-drained soil with a pH of 6.0–7.0. It tolerates poor soil better than most flowers, but it flowers best in soil improved with a little well-rotted compost — not too much, or you will get leaves instead of flowers. Space plants 9–12 inches apart so air can move between them. Water needs are moderate: keep the soil evenly moist while plants are young, then water in dry spells only — established calendula is fairly drought-tolerant. Water at the base in the morning so the foliage dries before night. The seed spacing calculator can help you plan the bed before you plant.
Companion planting
Good companions for calendula include lavender, marigolds, garlic and chives. Calendula is itself a superb companion plant: its flowers attract bees and hoverflies, and it is traditionally planted among vegetables — especially tomatoes and brassicas — to help deter pests. Plant it at the ends of vegetable beds and around fruit trees. Sweet peas are another cool-season Zone 9 flower that shares the autumn sowing window, and our guide to when to plant sweet peas in Zone 9 shows how the two can be timed together. The companion planting finder can suggest combinations for your whole bed.
Pests and problems
The common pests to watch for with calendula are aphids, slugs and thrips. Aphids cluster on buds and young shoots — wash them off with a strong jet of water, and the beneficial insects the flowers attract will help keep them in check. Slugs nibble young seedlings, especially after rain; hand-pick them after dark and keep mulch pulled back from the stems. Thrips can distort flowers in hot weather; healthy, well-spaced plants cope better.
Harvest and storage
Calendula takes 45–60 days to maturity from sowing, flowering from late autumn through spring in Zone 9. Pick the flowers little and often, in the morning, when they are fully open — regular picking keeps the plant producing new buds for months. Use the petals fresh in salads, or dry them for teas and skin preparations: spread the flower heads in a single layer in a shady, airy place until crisp, then store in a jar. Deadhead spent flowers if you want more blooms, or let a few plants set seed for self-sown seedlings next autumn.
Frequently asked questions
When should I plant calendula in Zone 9?
Sow in autumn (September–November) and again in late winter (January–March). Seeds germinate in 7–14 days and plants flower in 45–60 days. Avoid sowing in midsummer heat.
Are calendula flowers edible?
Yes — the petals are edible and are used in salads, teas and cooking. Pick flowers in the morning when fully open, and use the petals fresh or dried. Do not confuse calendula with French marigolds, which are not edible.
Do I need to deadhead calendula?
Yes, if you want more flowers — regular picking or deadheading keeps the plant producing new buds for months. Leave a few plants to set seed if you want self-sown seedlings next autumn.