Delhi, IA frost dates
Last spring frostMay 3median date
First fall frostOct 4median date
Growing season154 daysfrost-free
Hardiness zone5aZone 5a
How Delhi compares
- In 8 years out of 10, the last spring frost in Delhi falls between April 18 and May 16, a 28-day window. The first fall frost falls between September 22 and October 17.
- The median last frost is 5 days later than the Iowa median of Apr 28.
- Its 154-day growing season is longer than 10% of the 934 Iowa places with a regular frost season (state median 165 days).
- The last frost is typical for zone 5a, where the median is May 3.
- The weather station records an average of 158 nights a year at or below 32°F.
- Compared with Cedar Rapids, IA, 50 km away, the last frost here is 5 days later than there and the growing season is 13 days shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 18 |
| 50% (median) | May 3 |
| 10% (safe for tender plants) | May 16 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 22 |
| 50% (median) | October 4 |
| 90% (late) | October 17 |
Frost here means 32°F (0°C). A median date means half of years have their last frost earlier and half later.
Planting calendar for Delhi, IA
Delhi, IA frost dates — last frost May 3, first frost Oct 4, zone 5a. whenisthelastfrost.com
Crop
JFMAMJJASOND
Start indoors: Feb 8 to Feb 22Transplant outside: Apr 5 to Apr 19
Start indoors: Feb 22 to Mar 8Transplant outside: May 17 to May 31
Start indoors: Feb 22 to Mar 8Transplant outside: May 17 to May 31
Start indoors: Mar 8 to Mar 22Transplant outside: May 10 to May 24
Start indoors: Mar 8 to Mar 22Transplant outside: Apr 12 to Apr 26Sow outdoors: Apr 5 to May 10Plant for fall: Aug 9 to Sep 6
Start indoors: Mar 8 to Mar 22Transplant outside: Apr 5 to Apr 19Sow outdoors: Apr 5 to Apr 19Plant for fall: Jul 26 to Aug 16
Start indoors: Mar 8 to Mar 22Transplant outside: Apr 19 to May 3Plant for fall: Jun 28 to Jul 19
Start indoors: Mar 8 to Mar 22Transplant outside: Apr 12 to Apr 26Plant for fall: Jun 28 to Jul 19
Start indoors: Mar 8 to Mar 22Transplant outside: Apr 19 to May 3Plant for fall: Jun 28 to Jul 19
Start indoors: Mar 22 to Apr 5Transplant outside: May 24 to Jun 7Sow outdoors: May 24 to Jun 7
Start indoors: Mar 22 to Apr 5Transplant outside: May 10 to May 24
Sow outdoors: Mar 22 to Apr 12Plant for fall: Jul 12 to Aug 2
Sow outdoors: Mar 22 to Apr 12Plant for fall: Aug 9 to Aug 30
Sow outdoors: Mar 29 to May 10Plant for fall: Aug 23 to Sep 13
Start indoors: Apr 5 to Apr 12Transplant outside: May 17 to May 24Sow outdoors: May 10 to May 24Plant for fall: Jul 19 to Aug 2
Start indoors: Apr 5 to Apr 12Sow outdoors: May 10 to May 24Plant for fall: Jul 26 to Aug 9
Start indoors: Apr 5 to Apr 12Sow outdoors: May 10 to May 24
Start indoors: Apr 5 to Apr 12Transplant outside: May 17 to May 31
Sow outdoors: Apr 12 to May 10Plant for fall: Jul 12 to Jul 26
Sow outdoors: Apr 12 to May 10Plant for fall: Jul 26 to Aug 9
Sow outdoors: Apr 12 to May 3
Sow outdoors: Apr 19 to May 17Plant for fall: Jul 26 to Aug 9
Sow outdoors: Apr 19 to May 10Plant for fall: Aug 9 to Aug 30
Sow outdoors: May 10 to May 31Plant for fall: Jul 19 to Aug 2
Sow outdoors: May 10 to May 24
Transplant outside: May 17 to Jun 7
Plant for fall: Sep 20 to Oct 25
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Delhi, IA
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 8 – Feb 22 | Apr 5 – Apr 19 | — | — |
| Peppers | Feb 22 – Mar 8 | May 17 – May 31 | — | — |
| Eggplant | Feb 22 – Mar 8 | May 17 – May 31 | — | — |
| Tomatoes | Mar 8 – Mar 22 | May 10 – May 24 | — | — |
| Lettuce | Mar 8 – Mar 22 | Apr 12 – Apr 26 | Apr 5 – May 10 | Aug 9 – Sep 6 |
| Kale | Mar 8 – Mar 22 | Apr 5 – Apr 19 | Apr 5 – Apr 19 | Jul 26 – Aug 16 |
| Broccoli | Mar 8 – Mar 22 | Apr 19 – May 3 | — | Jun 28 – Jul 19 |
| Cabbage | Mar 8 – Mar 22 | Apr 12 – Apr 26 | — | Jun 28 – Jul 19 |
| Cauliflower | Mar 8 – Mar 22 | Apr 19 – May 3 | — | Jun 28 – Jul 19 |
| Okra | Mar 22 – Apr 5 | May 24 – Jun 7 | May 24 – Jun 7 | — |
| Basil | Mar 22 – Apr 5 | May 10 – May 24 | — | — |
| Peas | — | — | Mar 22 – Apr 12 | Jul 12 – Aug 2 |
| Spinach | — | — | Mar 22 – Apr 12 | Aug 9 – Aug 30 |
| Radishes | — | — | Mar 29 – May 10 | Aug 23 – Sep 13 |
| Cucumbers | Apr 5 – Apr 12 | May 17 – May 24 | May 10 – May 24 | Jul 19 – Aug 2 |
| Zucchini & Summer Squash | Apr 5 – Apr 12 | — | May 10 – May 24 | Jul 26 – Aug 9 |
| Winter Squash & Pumpkins | Apr 5 – Apr 12 | — | May 10 – May 24 | — |
| Melons & Watermelon | Apr 5 – Apr 12 | May 17 – May 31 | — | — |
| Carrots | — | — | Apr 12 – May 10 | Jul 12 – Jul 26 |
| Beets | — | — | Apr 12 – May 10 | Jul 26 – Aug 9 |
| Potatoes | — | — | Apr 12 – May 3 | — |
| Swiss Chard | — | — | Apr 19 – May 17 | Jul 26 – Aug 9 |
| Cilantro | — | — | Apr 19 – May 10 | Aug 9 – Aug 30 |
| Green Beans | — | — | May 10 – May 31 | Jul 19 – Aug 2 |
| Sweet Corn | — | — | May 10 – May 24 | — |
| Sweet Potatoes | — | May 17 – Jun 7 | — | — |
| Garlic | — | — | — | Sep 20 – Oct 25 |
Dates come from the median frost dates and common extension-service timing. Adjust for your soil temperature, microclimate and the varieties you grow.
About these dates
Based on 1991–2020 NOAA climate normals for the Manchester #2, IA weather station, 11 km away (elevation 991 ft (302 m)).
Frost dates near Delhi
- Delaware May 3 · Oct 4
- Earlville May 3 · Oct 4
- Manchester May 3 · Oct 4
- Hopkinton Apr 28 · Oct 10
- Ryan May 3 · Oct 7
- Greeley May 3 · Oct 4
- Dyersville Apr 28 · Oct 10
- Worthington Apr 28 · Oct 10
- Masonville May 3 · Oct 4
- Prairieburg May 3 · Oct 7
Frequently asked questions
When is the last frost in Delhi, IA?
The median last spring frost in Delhi, IA is May 3. There is still about a 10% chance of frost after May 16, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Delhi, IA?
The median first fall frost is October 4, with about a 10% chance of frost before September 22.
How long is the growing season in Delhi, IA?
About 154 days between the median last spring frost and first fall frost.
What planting zone is Delhi, IA?
Delhi, IA is in USDA hardiness zone 5a.