Frost Dates for Sioux City, IA 51104
Sioux City has 8 ZIP codes. The Sioux City, IA frost page lists all of them with their dates.
Last spring frost April 29 · First fall frost October 2 · 156 frost-free days · USDA Zone 5a
ZIP 51104 has about 23,200 people, one of 8 ZIP codes in Sioux City.
Moderate season: 156 frost-free days. Spring frost risk spans April 15–May 13 (28 days). Fall frost risk spans September 19–October 15 (26 days).
Frost probability for 51104
| Frost | 10% | 50% | 90% |
|---|---|---|---|
| Spring (last frost) | May 13 | April 29 | April 15 |
| Fall (first frost) | September 19 | October 2 | October 15 |
Dates come from NOAA 1971–2000 freeze probabilities at LE MARS (34.6 km away); the 50% date is the median year.
Which crops fit a 156-day season in Sioux City
In Sioux City (156 frost-free days, a moderate season), 32 of 56 planner crops fit outright, 23 get two plantings, 1 crop is perennial.
| Crop | Start indoors | Plant out / sow | Days you have | Verdict | Last sow date |
|---|---|---|---|---|---|
| Tomato | Mar 25 | May 13–May 20 | 114 | fits: 80 days to maturity, 114 available after May 13. | Jun 2 |
| Pepper | Mar 18 | May 13–May 20 | 114 | fits: 75 days to maturity, 114 available after May 13. | Jun 7 |
| Lettuce | Mar 4 | Apr 1–Apr 8 | 191 | two-plantings: Plant Apr 1 and again by Aug 11; both mature before Oct 9. | Aug 11 |
| Carrots | — | Apr 8–Apr 15 | 198 | fits: 70 days to maturity, 198 available after Apr 8. | Jul 31 |
| Cucumber | Apr 8 | May 13–May 20 | 128 | fits: 60 days to maturity, 128 available after May 13. | Jul 6 |
| Beans | — | May 6–May 20 | 142 | two-plantings: Plant May 6 and again by Jul 13; both mature before Sep 25. | Jul 13 |
| Peas | — | Mar 4–May 13 | 219 | fits: 65 days to maturity, 219 available after Mar 4. | Jul 22 |
| Zucchini | Apr 15 | May 13–May 20 | 128 | two-plantings: Plant May 13 and again by Jul 11; both mature before Sep 18. | Jul 11 |
| Onion | Feb 4 | Apr 1–Apr 15 | 191 | fits: 100 days to maturity, 191 available after Apr 1. | — |
| Spinach | — | Mar 4–Apr 22 | 233 | two-plantings: Plant Mar 4 and again by Aug 30; both mature before Oct 23. | Aug 30 |
| Kale | Feb 18 | Apr 1–Apr 15 | 205 | two-plantings: Plant Apr 1 and again by Aug 15; both mature before Oct 23. | Aug 15 |
| Broccoli | Mar 4 | Apr 1–Apr 15 | 191 | fits: 80 days to maturity, 191 available after Apr 1. | Jul 7 |
| Cabbage | Mar 4 | Apr 1–Apr 15 | 205 | fits: 70 days to maturity, 205 available after Apr 1. | Jul 31 |
| Radish | — | Mar 4–May 27 | 219 | two-plantings: Plant Mar 4 and again by Aug 31; both mature before Oct 9. | Aug 31 |
| Beets | — | Mar 4–May 27 | 219 | two-plantings: Plant Mar 4 and again by Aug 1; both mature before Oct 9. | Aug 1 |
| Potatoes | — | Apr 15–Apr 22 | 177 | fits: 90 days to maturity, 177 available after Apr 15. | — |
| Garlic | — | Oct 2 | 261 | overwinter: Plant Oct 2 to Oct 23; harvest the following summer. | Oct 23 |
| Strawberry | — | Mar 25–May 20 | 212 | perennial: A perennial: plant Mar 25; it fruits from the following year and keeps producing for several years. | — |
| Corn | Apr 1 | May 6–May 13 | 128 | fits: 75 days to maturity, 128 available after May 6. | Jun 14 |
| Pumpkin | Apr 15 | May 13–May 13 | 121 | fits: 100 days to maturity, 121 available after May 13. | May 20 |
| Cauliflower | Mar 18 | Apr 22–May 6 | 170 | fits: 75 days to maturity, 170 available after Apr 22. | Jul 12 |
| Swiss Chard | Mar 4 | Apr 15–Apr 15 | 177 | two-plantings: Plant Apr 15 and again by Aug 1; both mature before Oct 9. | Aug 1 |
| Arugula | — | Mar 4–May 27 | 233 | two-plantings: Plant Mar 4 and again by Aug 30; both mature before Oct 23. | Aug 30 |
| Brussel Sprouts | Mar 4 | Apr 1–Apr 15 | 205 | fits: 100 days to maturity, 205 available after Apr 1. | Jul 1 |
| Butternut Squash | Apr 15 | May 13–May 20 | 121 | fits: 100 days to maturity, 121 available after May 13. | May 20 |
| Eggplant | Mar 11 | May 13–May 20 | 114 | fits: 70 days to maturity, 114 available after May 13. | Jun 12 |
| Okra | Apr 1 | May 6–May 13 | 135 | two-plantings: Plant May 6 and again by Jul 11; both mature before Sep 18. | Jul 11 |
| Basil | Mar 25 | May 20–May 20 | 121 | fits: 60 days to maturity, 121 available after May 20. | Jul 6 |
| Cilantro | — | Apr 1–Apr 22 | 191 | two-plantings: Plant Apr 1 and again by Aug 6; both mature before Oct 9. | Aug 6 |
| Parsley | Feb 18 | May 6–May 13 | 156 | fits: 70 days to maturity, 156 available after May 6. | Jul 17 |
| Celery | Feb 18 | May 6–May 20 | 156 | fits: 120 days to maturity, 156 available after May 6. | May 28 |
| Scallions | Feb 18 | Apr 1–Apr 15 | 205 | two-plantings: Plant Apr 1 and again by Aug 10; both mature before Oct 23. | Aug 10 |
| Turnip | — | Apr 1–Apr 15 | 205 | two-plantings: Plant Apr 1 and again by Aug 20; both mature before Oct 23. | Aug 20 |
| Kohlrabi | — | Mar 18–Apr 1 | 219 | two-plantings: Plant Mar 18 and again by Aug 15; both mature before Oct 23. | Aug 15 |
| Bok Choy | Apr 1 | Apr 22–Apr 29 | 170 | two-plantings: Plant Apr 22 and again by Aug 11; both mature before Oct 9. | Aug 11 |
| Collards | Feb 18 | Apr 1–Apr 15 | 205 | two-plantings: Plant Apr 1 and again by Aug 10; both mature before Oct 23. | Aug 10 |
| Cantaloupe | Apr 15 | May 13–May 20 | 114 | fits: 85 days to maturity, 114 available after May 13. | May 28 |
| Chives | Feb 4 | May 6–May 13 | 170 | fits: 90 days to maturity, 170 available after May 6. | — |
| Dill | — | Mar 4–May 27 | 219 | two-plantings: Plant Mar 4 and again by Aug 1; both mature before Oct 9. | Aug 1 |
| Oregano | Feb 18 | May 6–May 13 | 170 | fits: 80 days to maturity, 170 available after May 6. | — |
| Rosemary | Feb 4 | May 6–May 13 | 156 | fits: 80 days to maturity, 156 available after May 6. | — |
| Sage | Mar 4 | May 6–May 13 | 170 | fits: 75 days to maturity, 170 available after May 6. | — |
| Thyme | Feb 18 | May 6–May 13 | 170 | fits: 90 days to maturity, 170 available after May 6. | — |
| Calendula | Mar 18 | Apr 15–Apr 29 | 177 | two-plantings: Plant Apr 15 and again by Aug 6; both mature before Oct 9. | Aug 6 |
| Cosmos | Apr 1 | Apr 29–May 13 | 142 | two-plantings: Plant Apr 29 and again by Jul 6; both mature before Sep 18. | Jul 6 |
| Lavender | Feb 4 | Apr 29–May 13 | 177 | fits: 90 days to maturity, 177 available after Apr 29. | — |
| Marigolds | Mar 18 | Apr 29–May 6 | 142 | two-plantings: Plant Apr 29 and again by Jul 16; both mature before Sep 18. | Jul 16 |
| Melons | Apr 15 | May 13–May 20 | 114 | fits: 85 days to maturity, 114 available after May 13. | May 28 |
| Mint | — | Apr 29–May 13 | 177 | fits: 90 days to maturity, 177 available after Apr 29. | — |
| Nasturtiums | Apr 1 | Apr 29–May 6 | 142 | two-plantings: Plant Apr 29 and again by Jul 11; both mature before Sep 18. | Jul 11 |
| Pole Beans | — | May 6–May 20 | 135 | fits: 65 days to maturity, 135 available after May 6. | Jul 1 |
| Spaghetti Squash | Apr 15 | May 13–May 20 | 121 | fits: 90 days to maturity, 121 available after May 13. | May 30 |
| Sunflowers | — | Apr 29–May 13 | 142 | fits: 70 days to maturity, 142 available after Apr 29. | Jun 26 |
| Tomatillos | Mar 4 | May 6–May 13 | 121 | fits: 75 days to maturity, 121 available after May 6. | Jun 7 |
| Watermelon | Apr 15 | May 6–May 13 | 121 | fits: 80 days to maturity, 121 available after May 6. | Jun 2 |
| Yellow Squash | Apr 15 | May 13–May 20 | 128 | two-plantings: Plant May 13 and again by Jul 11; both mature before Sep 18. | Jul 11 |
| Zinnias | Apr 1 | Apr 29–May 13 | 142 | two-plantings: Plant Apr 29 and again by Jul 6; both mature before Sep 18. | Jul 6 |
Month by month in Sioux City
| Month | What to do |
|---|---|
| January | Plan your garden layout and order seeds. Research varieties suited to your frost dates. |
| February | Start indoors: Chives (Feb 4), Lavender (Feb 4), Onion (Feb 4), Rosemary (Feb 4), Celery (Feb 18), Collards (Feb 18), +5 more. |
| March | Start indoors: Broccoli (Mar 4), Brussel Sprouts (Mar 4), Cabbage (Mar 4), Lettuce (Mar 4), Sage (Mar 4), Swiss Chard (Mar 4), +8 more. Direct sow from: Arugula (Mar 4), Beets (Mar 4), Dill (Mar 4), Peas (Mar 4), Radish (Mar 4), Spinach (Mar 4), +1 more. Plant: Strawberry (Mar 25). |
| April | Start indoors: Bok Choy (Apr 1), Corn (Apr 1), Cosmos (Apr 1), Nasturtiums (Apr 1), Okra (Apr 1), Zinnias (Apr 1), +9 more. Direct sow from: Cilantro (Apr 1), Turnip (Apr 1), Carrots (Apr 8), Potatoes (Apr 15), Sunflowers (Apr 29). Transplant from: Broccoli (Apr 1), Brussel Sprouts (Apr 1), Cabbage (Apr 1), Collards (Apr 1), Kale (Apr 1), Lettuce (Apr 1), +12 more. Last frost around April 29. |
| May | Direct sow from: Beans (May 6), Pole Beans (May 6). Transplant from: Celery (May 6), Chives (May 6), Corn (May 6), Okra (May 6), Oregano (May 6), Parsley (May 6), +17 more. Last sowing dates: Butternut Squash (May 20), Pumpkin (May 20), Cantaloupe (May 28), Celery (May 28), Melons (May 28), Spaghetti Squash (May 30). |
| June | Last sowing dates: Tomato (Jun 2), Watermelon (Jun 2), Pepper (Jun 7), Tomatillos (Jun 7), Eggplant (Jun 12), Corn (Jun 14), +1 more. |
| July | Last sowing dates: Brussel Sprouts (Jul 1), Pole Beans (Jul 1), Basil (Jul 6), Cosmos (Jul 6), Cucumber (Jul 6), Zinnias (Jul 6), +12 more. |
| August | Last sowing dates: Beets (Aug 1), Dill (Aug 1), Swiss Chard (Aug 1), Calendula (Aug 6), Cilantro (Aug 6), Collards (Aug 10), +9 more. |
| September | First fall frost approaching (around October 2). Transplant fall brassicas. Sow spinach, arugula, and radishes. |
| October | Direct sow from: Garlic (Oct 2). First frost around October 2. Last sowing dates: Garlic (Oct 23). |
| November | Harvest remaining cold-hardy crops: kale, carrots, and beets. Plant garlic bulbs for next year. |
| December | Clean up spent plants. Add compost to beds. Rest, review, and plan next year's garden. |
Frequently Asked Questions
What is the last frost date for Sioux City, IA (ZIP 51104)?
The median last spring frost date for Sioux City, IA (ZIP code 51104) is around April 29. This is the 50th-percentile date — meaning half of all years see frost end before this date. Use the 10% and 90% dates to understand the full range of risk in your area. One year in ten frost ends before April 15; one in ten it runs past May 13.
What is the first fall frost date in Sioux City, IA?
The median first fall frost date for Sioux City, IA is around October 2. Plan to harvest or protect frost-sensitive crops like tomatoes and peppers at least a week before this date to avoid losses. The first frost arrives around September 19 in the earliest one-in-ten years, so cover tomatoes and peppers from then.
How long is the growing season in Sioux City, IA?
The frost-free growing season in Sioux City is about 156 days. This window — from your last spring frost to your first fall frost — is when warm-season vegetables thrive. Cold-hardy crops like kale, spinach, and peas can extend your season by weeks on either side. In Sioux City (156 frost-free days, a moderate season), 32 of 56 planner crops fit outright, 23 get two plantings, 1 crop is perennial.
What USDA hardiness zone is Sioux City, IA?
Sioux City, IA is in USDA hardiness zone 5a (2023 USDA Plant Hardiness Zone Map). Zones come from the average coldest winter temperature, so they tell you which perennials survive the winter; the frost dates on this page tell you when to plant.
When should I start tomatoes indoors in Sioux City, IA?
Start tomatoes indoors Mar 25 and plant out May 13 in Sioux City. The planner uses the local median last frost and this crop's indoor-start and transplant offsets.
How many plantings of lettuce fit in Sioux City?
Two: plant Apr 1 and again by Aug 11; both mature before Oct 9.
When do I plant garlic in Sioux City?
Oct 2 to Oct 23; it overwinters and is ready the following summer.
Nearby and related
- Frost dates for South Sioux City, NE 68776 (5.6 mi)
- Frost dates for Sioux City, IA 51106 (6.6 mi)
- Frost dates for Le Mars, IA 51031 (21.7 mi)
- Frost dates for Vermillion, SD 57069 (36.5 mi)
- Frost dates for Yankton, SD 57078 (59.2 mi)
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