When to plant marigolds by city
Start marigolds indoors 6–8 weeks before your last frost, plant them out 1–2 weeks after your last frost, or sow seed outdoors 1–3 weeks after your last frost, once the soil is at least 60°F. Here is what that means for 2027 in cities across the US, using each city’s average frost dates and the date its normal daily temperature reaches 60°F, so cool-spring places like Seattle wait for real warmth (NOAA 1991–2020). Pick the city with the climate most like yours, or enter your ZIP code above.
| City | Last frost | Start indoors | Plant out | Sow outdoors |
|---|---|---|---|---|
| Seattle, WA (9a) | Mar 13 | Mar 27 – Apr 10 | May 29 – Jun 5 | May 29 – Jun 12 |
| Portland, OR (8b) | Feb 25 | Mar 22 – Apr 5 | May 24–31 | May 24 – Jun 7 |
| Sacramento, CA (9b) | Jan 12 | Feb 1–15 | Apr 5–12 | Apr 5–19 |
| Phoenix, AZ (10a) | Jan 5 | Dec 14–28 | Feb 15–22 | Feb 15 – Mar 1 |
| Salt Lake City, UT (7b) | Mar 31 | Mar 6–20 | May 8–15 | May 8–22 |
| Denver, CO (6a) | Apr 30 | Mar 15–29 | May 17–24 | May 17–31 |
| Dallas, TX (8b) | Mar 2 | Jan 13–27 | Mar 17–24 | Mar 17–31 |
| Minneapolis, MN (5a) | Apr 23 | Mar 17–31 | May 19–26 | May 19 – Jun 2 |
| Kansas City, MO (6b) | Apr 4 | Feb 21 – Mar 7 | Apr 25 – May 2 | Apr 25 – May 9 |
| Chicago, IL (6b) | Apr 10 | Mar 20 – Apr 3 | May 22–29 | May 22 – Jun 5 |
| Columbus, OH (6b) | Apr 20 | Mar 5–19 | May 7–14 | May 7–21 |
| Nashville, TN (7b) | Apr 1 | Feb 12–26 | Apr 16–23 | Apr 16–30 |
| Atlanta, GA (8a) | Mar 24 | Feb 4–18 | Apr 8–15 | Apr 8–22 |
| Raleigh, NC (8a) | Mar 28 | Feb 9–23 | Apr 13–20 | Apr 13–27 |
| Philadelphia, PA (7b) | Mar 30 | Feb 23 – Mar 9 | Apr 27 – May 4 | Apr 27 – May 11 |
| Boston, MA (7a) | Apr 4 | Mar 18 – Apr 1 | May 20–27 | May 20 – Jun 3 |
In frost-free parts of Florida, southern California and the Gulf Coast, timing is about heat instead: plant marigolds in late winter or early spring and again in late summer.
Don’t go by the calendar alone. Marigolds planted into cold soil sit still for weeks; wait until the soil 4 inches down is at least 60°F and nights stay above 50°F.
Marigold spacing
In a square-foot bed, plant 4 per square foot. In traditional rows, space plants about 8 inches apart with 12 inches between rows.
French marigolds suppress root-knot nematodes when grown densely for a season.
How to grow marigolds
Marigolds are tough, cheerful annuals that bloom from early summer to frost with little care. Compact French marigolds suit bed edges, tall African types make a bold mass, and small signet types have lacy foliage and edible flowers.
Sun and soil
Full sun and well-drained soil with a pH of about 5.5–7.0. About 1 inch of water a week; let the soil dry a little between waterings.
Planting
- Start seeds indoors 6–8 weeks before the last frost (African types need the longer end), ¼ inch deep at 70–75°F. They sprout in about a week.
- Transplant 1–2 weeks after the last frost, or direct-sow ¼ inch deep 1–3 weeks after it, once soil reaches 60°F.
- Space French marigolds 8 inches apart in rows 12 inches apart; give African types 12–16 inches.
Care
- Deadhead spent flowers to keep plants blooming.
- Skip heavy fertilizer, which gives leaves instead of flowers.
- Stake tall African marigolds in windy spots.
- To suppress root-knot nematodes, French marigolds must be grown densely as a solid planting for a full season, then turned under. A few plants scattered among vegetables do not protect them.
Harvest
Cut flowers for vases when fully open. Signet marigold petals have a citrusy flavor for salads. You can save seed from open-pollinated varieties (not hybrids) by letting a few heads dry on the plant.
Common problems
- Spider mites: Stippled, dusty-looking leaves in hot, dry weather. Hose off leaf undersides and keep plants watered.
- Gray mold (Botrytis): Brown, fuzzy rot on flowers in wet weather. Remove spent and moldy blooms and space plants for airflow.
- Slugs: They chew seedlings in damp spots. Hand-pick and use traps.
- Aster yellows: Distorted, greenish flowers and yellow, stunted growth, spread by leafhoppers. Pull and discard infected plants.
Varieties to try
- 'Bonanza' — compact French marigold, 10–12 inches
- 'Durango' — French type with large flowers
- 'Crackerjack' — tall African type, about 3 feet
- 'Tangerine Gem' — signet type with edible orange flowers
Crop rotation
Marigolds belong to the daisy family (Asteraceae). Few shared soil problems; fits anywhere in a rotation. Relatives that count as the same family for rotation: lettuce, red leaf lettuce, sunflower, calendula, zinnia.
Frequently asked questions
When should I plant marigolds?
What grows well with marigolds?
How far apart should I plant marigolds?
How long do marigolds take to grow?
Can marigolds handle frost?
Sources
- Frost dates: NOAA National Centers for Environmental Information, U.S. Climate Normals 1991–2020.
- Hardiness zones: 2023 USDA Plant Hardiness Zone Map, USDA-ARS and PRISM Climate Group, Oregon State University.
- Planting windows and spacing: Vegetable Planting Guide (GardenNotes #720), Colorado State University Extension, and other land-grant extension guides.
- Marigolds (Tagetes spp.) for Nematode Management (ENY-056), Krueger, Dover, McSorley & Wang, University of Florida IFAS Extension
- Gardening with Companion Plants (EM128E), Linda Chalker-Scott, Washington State University Extension, 2023
- Marigold — Clemson Cooperative Extension (HGIC)