When to plant · 14 cities · zones 5a–5b
When to plant basil in Iowa
Start Genovese Basil seeds indoors around Mar 31 and transplant around May 12 — the Iowa statewide median, counted from a last spring frost of Apr 28 across 964 ZIP codes and 160 NOAA stations.
The rule: Basil is damaged below about 50 °F, well before frost: transplant two weeks after the last frost, not on it.
Iowa basil, by step
Statewide median last frost Apr 28, first fall frost Oct 10, 2027 season. Each cultivar's own indoor lead time and days to maturity, same engine as the Plan Builder.
| Cultivar | Start indoors | Plant out | First harvest | Days |
|---|---|---|---|---|
| Genovese BasilGenovese | Mar 31 | May 12 | Jul 11 | 60 from transplant |
Tight means first harvest lands within two weeks of the median first fall frost. Statewide dates are the ZIP-weighted median of every NOAA 1991–2020 station Iowa's ZIP codes resolve to.
Basil in Iowa, city by city
Genovese Basil, scheduled from each city's nearest NOAA station — the same dates as its frost page.
| City | Last frost | Start indoors | Plant out | First harvest |
|---|---|---|---|---|
| Des Moineszone 5b | Apr 18 | Mar 21 | May 2 | Jul 1 |
| Cedar Rapidszone 5b | Apr 28 | Mar 31 | May 12 | Jul 11 |
| Davenportzone 5b | Apr 23 | Mar 26 | May 7 | Jul 6 |
| Sioux Cityzone 5a | Apr 29 | Apr 1 | May 13 | Jul 12 |
| Ankenyzone 5b | Apr 23 | Mar 26 | May 7 | Jul 6 |
| Iowa Cityzone 5b | Apr 21 | Mar 24 | May 5 | Jul 4 |
| West Des Moineszone 5b | Apr 18 | Mar 21 | May 2 | Jul 1 |
| Ameszone 5b | Apr 26 | Mar 29 | May 10 | Jul 9 |
| Waterloozone 5a | Apr 27 | Mar 30 | May 11 | Jul 10 |
| Council Bluffszone 5b | Apr 18 | Mar 21 | May 2 | Jul 1 |
| Dubuquezone 5a | Apr 19 | Mar 22 | May 3 | Jul 2 |
| Urbandalezone 5b | Apr 18 | Mar 21 | May 2 | Jul 1 |
| Marionzone 5a | Apr 28 | Mar 31 | May 12 | Jul 11 |
| Cedar Fallszone 5a | Apr 27 | Mar 30 | May 11 | Jul 10 |
What these basil become
What Iowa basil need
Genovese Sweet Basil Seed
The large-leaf, low-anise Italian basil that pesto is defined by. Thai and lemon basils are good plants and wrong ingredients.
Organic Seed Starter Potting MixMust have
Seed-starting mix is not potting soil with a nicer label — it is finer, lighter, and low in nutrients on purpose, because a seedling's first roots want air and moisture, not fertiliser.
T8 Full-Spectrum Grow Lights, 1 ft 4-packMust have
A south window in March delivers a fraction of the light a pepper seedling needs, and the plant tells you by stretching. Two inches of LED above the canopy for 16 hours a day fixes it permanently.
5-Gallon Fabric Grow Bags, 5-Pack
Fabric pots air-prune roots and drain faster than a plastic pot can, which is the entire reason container tomatoes fail. Five gallons is the honest minimum for a pepper; a tomato wants ten.
Ocean Forest Potting SoilMust have
Pre-charged with enough nutrition to carry a transplant for its first month without feeding, which is exactly the window when most container plants stall.
6" Micro-Tip Pruning SnipsMust have
Ninety percent of sauce-garden cutting is snipping a pepper stem or a basil node, and a fine-tipped snip does it better than any pruner. Pulling peppers by hand tears the branch.
Mesh Strainers, Stainless, 3-Count
The last pass before bottling. A fine mesh catches the skin fragments and seed shards that make a hot sauce gritty and clog a woozy bottle's dripper insert.
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Basil in Iowa: questions
When should I plant basil in Iowa?
Transplant around May 12 at the statewide median; across the state that date runs from May 4 in the warmest tenth of Iowa's ZIP codes to May 17 in the coldest. To cut the freeze risk to one year in ten, count from May 11 instead of the median last frost. Use the city table for your own town.
When do I start basil seeds indoors in Iowa?
Around Mar 31 for Genovese Basil: 4 weeks before the statewide median last frost, on soil held at 70–80 °F.
When is the last frost in Iowa?
The ZIP-weighted median of NOAA 1991–2020 station medians is Apr 28. In the warmest tenth of Iowa's ZIP codes the median last frost falls on or before Apr 20; in the coldest tenth, on or after May 3.
When will Iowa basil be ready to harvest?
Genovese Basil planted on the statewide date is ready around Jul 11: 60 days from transplant.
More for Iowa
- When to plant tomatoes
- When to plant peppers
- When to plant tomatillos
- When to plant onions
- When to plant cilantro
- When to plant carrots
- When to plant mustard greens
Basil in every state → · Iowa frost dates → · How frost-date math works →