Clarendon, AR planting calendar
- USDA zone
- 8a10 to 15 °F
- Last frost
- Mar 15avg, 32°F
- First frost
- Nov 11avg, 32°F
- Growing season
- 241days
Clarendon, Arkansas is in USDA plant hardiness zone 8a. Its average last spring frost is around March 15 and the first fall frost around November 11, giving a growing season of about 241 days (NOAA 1991–2020 normals, 32°F, median). Start tender crops like tomatoes and peppers indoors weeks before the last frost and set them out afterward; sow hardy crops such as peas, spinach, and lettuce before it. The planner below turns those frost dates into a printable per-crop planting calendar.
Clarendon planting calendar
Each crop's windows are counted from Clarendon's average frost dates. hatched = start seeds indoors, solid green = plant out, teal = a fall sowing, and the terracotta dot marks the estimated first harvest. Ranges are extension-guide planning guidance, not guarantees.
- Start indoors
- Plant out
- Fall sowing
- First harvest
| Crop | Frost tolerance | Start indoors | Plant out | First harvest | Fall planting |
|---|---|---|---|---|---|
| Tomato | Tender | Jan 18 – Feb 1 | Mar 22 – Mar 29 | May 21 – Jun 10 | — |
| Pepper | Very tender | Jan 4 – Jan 18 | Mar 29 – Apr 5 | May 28 – Jun 27 | — |
| Cucumber | Tender | Feb 15 – Feb 22 | Mar 22 – Mar 29 | May 11 – May 31 | — |
| Summer squash / zucchini | Tender | — | Mar 22 – Mar 29 | May 6 – May 21 | — |
| Bush bean | Tender | — | Mar 22 – Mar 29 | May 11 – May 21 | Sep 12 – Sep 22 |
| Sweet corn | Tender | — | Mar 15 – Mar 29 | May 14 – Jun 13 | — |
| Basil | Very tender | Feb 1 – Feb 15 | Mar 22 – Mar 29 | Apr 21 – May 6 | — |
| Lettuce | Half-hardy | Feb 1 – Feb 15 | Feb 15 – Mar 1 | Apr 1 – Apr 16 | Aug 29 – Sep 13 |
| Pea | Hardy | — | Feb 1 – Feb 15 | Mar 28 – Apr 12 | Aug 19 – Sep 3 |
| Spinach | Hardy | — | Feb 1 – Feb 15 | Mar 13 – Mar 23 | Sep 8 – Sep 18 |
| Carrot | Half-hardy | — | Feb 22 – Mar 1 | Apr 23 – May 13 | Aug 9 – Aug 29 |
| Broccoli | Half-hardy | Jan 18 – Feb 1 | Feb 15 – Mar 1 | Apr 11 – May 1 | Aug 14 – Sep 3 |
Data: NOAA NCEI U.S. Climate Normals 1991–2020 (public domain) and USDA Plant Hardiness Zone Map 2023. Planting windows synthesized from U.S. Cooperative Extension guides.
Frost & freeze dates
From NOAA's 1991–2020 Climate Normals at station USC00031442. The median (p50) is the average date; the 90%-safe column is the date the freeze has passed in about 9 years out of 10 (p10 for spring, p90 for fall) — the conservative date to plant after or harvest before.
| Threshold | Last spring — avg | Last spring — 90%-safe | First fall — avg | First fall — 90%-safe | Season (days) |
|---|---|---|---|---|---|
| 36°F | Mar 29 | Apr 14 | Nov 1 | Nov 16 | 218 |
| 32°F (freeze) | Mar 15 | Apr 1 | Nov 11 | Nov 30 | 241 |
| 28°F | Mar 2 | Mar 19 | Nov 24 | Dec 19 | 267 |
| 24°F | Feb 18 | Mar 9 | Dec 11 | Jan 9 | 296 |
32°F is the standard "freeze" line that damages tender crops; lighter 36°F frost can nip the most cold-sensitive plants, while hardy crops shrug off light frost down toward 28°F. Use the threshold that matches what you are protecting.
Growing degree days
Growing degree days (GDD) accumulate warmth above a base temperature over the year — a better predictor of crop development than the calendar alone. Warm-season crops need a long, warm GDD total; a short, cool GDD total favors greens and brassicas.
| Model | °F·days | Used for |
|---|---|---|
| Base 50°F (warm-season) | 5,256 | standard warm-season base (tomato, corn, beans) |
| Base 40°F (cool-season) | 8,166 | cool-season crops (brassicas, greens) |
Hardiness zone 8a
Clarendon sits in USDA plant hardiness zone 8a on the 2023 map — meaning its average annual extreme minimum winter temperature is about 10 to 15 °F. That number tells you which perennials, shrubs, and trees reliably survive an average winter here; it does not set your planting dates, which come from the frost calendar above.
Explore more places in zone 8a, or see all USDA hardiness zones.
Frequently asked questions
- What USDA hardiness zone is Clarendon?
- Clarendon, Arkansas is in USDA plant hardiness zone 8a on the 2023 map (average annual extreme minimum temperature 10 to 15 °F) — from the USDA Plant Hardiness Zone Map 2023, matched to this location's ZIP. See the methodology page for sources.
- When is the last frost in Clarendon?
- The average (median) last spring frost at 32°F is around March 15, from NOAA's 1991–2020 climate normals at the nearest reporting station. Roughly one year in ten the last frost is as late as April 1, so wait until then before setting out frost-tender plants if you want to be safe.
- When is the first fall frost in Clarendon?
- The average first fall frost at 32°F is around November 11. That leaves a growing season of about 241 days between the average last spring and first fall frosts.
- When should I start tomatoes in Clarendon?
- Start tomato seeds indoors about Jan 18 – Feb 1 and transplant them outside about Mar 22 – Mar 29, once the danger of frost has passed. Estimated first harvest is around May 21 – Jun 10.
- How long is the growing season in Clarendon?
- About 241 days at the 32°F threshold (NOAA 1991–2020, median) — the span between the average last spring frost (~March 15) and the average first fall frost (~November 11). Cold-hardy crops extend usable time at both ends; frost-tender crops fit inside it.
Sources & method
Frost, freeze, growing-season, and growing-degree-day figures are NOAA NCEI U.S. Climate Normals 1991–2020 for station USC00031442 (Clarendon, 2.7 km away). The hardiness zone is the USDA Plant Hardiness Zone Map 2023, matched to this location's ZIP. Planting windows are computed by counting from the average last and first frost using per-crop offsets synthesized from U.S. Cooperative Extension guides — the full method and citations are on the methodology page.