When to Plant Nasturtiums
Nasturtiums are a tender warm-season flower. Frost damages them, so they go out only after the last spring frost.
Start seeds indoors 3 to 5 weeks before the last spring frost, and plant out from the last frost to 2 weeks after it. Or sow them where they will grow, from the last spring frost to 2 weeks after it. The first flowers open about 45 to 60 days after sowing.
Example dates
The same rules in dates for three climates, using typical frost dates. Enter your ZIP code above for the dates where you live.
| Task | Last frost Mar 15first Nov 15 | Last frost Apr 15first Oct 25 | Last frost May 15first Sep 30 |
|---|---|---|---|
| Start seeds indoors | Feb 8 – 22 | Mar 11 – 25 | Apr 10 – 24 |
| Harden off | Mar 8 – 14 | Apr 8 – 14 | May 8 – 14 |
| Plant out | Mar 15 – 29 | Apr 15 – 29 | May 15 – 29 |
| In flower | Mar 25 – Jun 3 | Apr 25 – Jul 4 | May 25 – Aug 3 |
| Direct-sown: Sow outdoors | Mar 15 – 29 | Apr 15 – 29 | May 15 – 29 |
| Direct-sown: In flower | Apr 29 – Jul 8 | May 30 – Aug 8 | Jun 29 – Sep 7 |
Growing nasturtiums
Nasturtiums flower best in lean soil; rich ground gives lots of leaves and few blooms.
- Spacing: 10 in apart, in rows 18 in apart. In a raised bed, 1 per sq ft at square-foot spacing.
- Days to first flowers: 45 to 60 from sowing, then about 10 weeks of flowers.
- Traditional companions: broccoli, brussels sprouts, cantaloupe, cauliflower, celery, cherry tomato, collards, cucumber, kale, kohlrabi, pea (shelling/snap/snow), pumpkin, radish, summer squash (zucchini/yellow), tomato, watermelon, winter squash. See companion plants for nasturtiums.
Plan your beds with these dates
Draw your beds, tap squares to plant nasturtiums and everything else, and get every crop's dates for your ZIP code in one calendar. Free, in your browser.
Open the garden plannerQuestions
When do I start nasturtiums indoors?
3 to 5 weeks before the last spring frost: with a last frost of April 15, that's Mar 11 – 25. Enter your ZIP code above for your own dates.
Can nasturtiums go in before the last frost?
No. Nasturtiums are damaged by frost: plant them out from the last spring frost to 2 weeks after it.
How long do nasturtiums take to grow?
About 45 to 60 days from sowing to the first flowers, which then lasts about 10 weeks. Varieties differ: check the seed packet.
More planting dates
Sources
- NOAA National Centers for Environmental Information, U.S. Climate Normals 1991–2020 (annual/seasonal, by station: freeze dates at 32 °F)
- Iowa State: Germination Requirements for Annuals and Vegetables
- Colorado State University Extension: Growing Annual Plants from Seed
- Colorado State University Extension: How to grow, harvest and eat 12 tasty edible annual flowers in Colorado
- Clemson Cooperative Extension HGIC: Growing Annuals
- UC Master Gardener Program, UC ANR: Companion Planting Chart: Companion Planting for Edible Crops
- University of Wisconsin–Madison Extension, Kenosha County: Companion Plants for the Vegetable Garden (column, 2012)
- Oregon State University Extension Service: Herbs and Flowers in the Vegetable Garden
- Utah State University Extension, Utah 4-H: Creating Sustainable School and Home Gardens: Companion Planting (2025)
- University of Arizona Cooperative Extension, Yavapai County: The Art of Companion Planting (Master Gardener presentation, 2023)