Liberty, MO 64089 planting calendar

USDA hardiness zone 6a · nearest station Smithville Lake (1.3 km) · NOAA 1991–2020 normals

USDA zone
6a−10 to −5 °F
Last frost
Apr 18avg, 32°F
First frost
Oct 20avg, 32°F
Growing season
183days

Liberty, Missouri is in USDA plant hardiness zone 6a. Its average last spring frost is around April 18 and the first fall frost around October 20, giving a growing season of about 183 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.

Liberty planting calendar

Each crop's windows are counted from Liberty'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
Planting windows for Liberty. Dates are planning ranges from U.S. Cooperative Extension guides.
Crop Frost tolerance Start indoors Plant out First harvest Fall planting
Tomato Tender Feb 21 – Mar 7 Apr 25 – May 2 Jun 24 – Jul 14
Pepper Very tender Feb 7 – Feb 21 May 2 – May 9 Jul 1 – Jul 31
Cucumber Tender Mar 21 – Mar 28 Apr 25 – May 2 Jun 14 – Jul 4
Summer squash / zucchini Tender Apr 25 – May 2 Jun 9 – Jun 24
Bush bean Tender Apr 25 – May 2 Jun 14 – Jun 24 Aug 21 – Aug 31
Sweet corn Tender Apr 18 – May 2 Jun 17 – Jul 17
Basil Very tender Mar 7 – Mar 21 Apr 25 – May 2 May 25 – Jun 9
Lettuce Half-hardy Mar 7 – Mar 21 Mar 21 – Apr 4 May 5 – May 20 Aug 7 – Aug 22
Pea Hardy Mar 7 – Mar 21 May 1 – May 16 Jul 28 – Aug 12
Spinach Hardy Mar 7 – Mar 21 Apr 16 – Apr 26 Aug 17 – Aug 27
Carrot Half-hardy Mar 28 – Apr 4 May 27 – Jun 16 Jul 18 – Aug 7
Broccoli Half-hardy Feb 21 – Mar 7 Mar 21 – Apr 4 May 15 – Jun 4 Jul 23 – Aug 12

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 USC00237862. 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.

Freeze probabilities by temperature threshold (MM/DD, NOAA 1991–2020).
Threshold Last spring — avg Last spring — 90%-safe First fall — avg First fall — 90%-safe Season (days)
36°F Apr 28 May 13 Oct 10 Oct 23 164
32°F (freeze) Apr 18 May 3 Oct 20 Nov 1 183
28°F Apr 7 Apr 23 Oct 29 Nov 11 204
24°F Mar 29 Apr 14 Nov 5 Nov 23 223

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.

Annual growing degree days for Liberty (°F·days, NOAA 1991–2020).
Model °F·days Used for
Base 50°F (warm-season) 3,705 standard warm-season base (tomato, corn, beans)
Base 40°F (cool-season) 6,028 cool-season crops (brassicas, greens)

Hardiness zone 6a

Liberty sits in USDA plant hardiness zone 6a on the 2023 map — meaning its average annual extreme minimum winter temperature is about −10 to −5 °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 6a, or see all USDA hardiness zones.

Frequently asked questions

What USDA hardiness zone is Liberty?
Liberty, Missouri is in USDA plant hardiness zone 6a on the 2023 map (average annual extreme minimum temperature −10 to −5 °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 Liberty?
The average (median) last spring frost at 32°F is around April 18, from NOAA's 1991–2020 climate normals at the nearest reporting station. Roughly one year in ten the last frost is as late as May 3, so wait until then before setting out frost-tender plants if you want to be safe.
When is the first fall frost in Liberty?
The average first fall frost at 32°F is around October 20. That leaves a growing season of about 183 days between the average last spring and first fall frosts.
When should I start tomatoes in Liberty?
Start tomato seeds indoors about Feb 21 – Mar 7 and transplant them outside about Apr 25 – May 2, once the danger of frost has passed. Estimated first harvest is around Jun 24 – Jul 14.
How long is the growing season in Liberty?
About 183 days at the 32°F threshold (NOAA 1991–2020, median) — the span between the average last spring frost (~April 18) and the average first fall frost (~October 20). 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 USC00237862 (Smithville Lake, 1.3 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.