Harmon County, OK — Planting Guide
Harmon County is in USDA Zone 7b. The average last spring frost is March 31 and the first fall frost is November 5, giving you a growing season of approximately 219 days.
At an elevation of 993 ft, Harmon County receives approximately 34.4 in of rainfall annually. Summer highs average 91°F with winter lows around 34°F. The predominant soil type is Loam.
Based on 31 years of NOAA climate station data, the last frost date here varies by 32 days year to year — ranging from March 14 in warm years to April 15 in cold years. Harmon County scores 69/100 (Good) on the Microclimate Index.
🌡️ Zone
7b (5°F to 10°F min)
❄️ Last Frost
March 31
🍂 First Frost
November 5
📅 Growing Season
219 days
⛰️ Elevation
993 ft
🌧️ Annual Rainfall
34.4 in
Monthly Watering Calendar
When you'll need to water your garden — based on average monthly rainfall vs. the ~1 inch/week most gardens need.
View detailed monthly data
| Month | Avg Rainfall | Rainy Days | Extra Water Needed | Watering Effort |
|---|---|---|---|---|
| Jan | 0.9 in | 3 days | — | None |
| Feb | 1.2 in | 5 days | — | None |
| Mar | 2.3 in | 6 days | 2 in | High |
| Apr | 3.7 in | 7 days | 0.6 in | Moderate |
| May | 5.1 in | 9 days | — | Low |
| Jun | 5 in | 9 days | — | Low |
| Jul | 4.1 in | 8 days | 0.2 in | Low |
| Aug | 4.8 in | 7 days | — | Low |
| Sep | 3 in | 5 days | 1.3 in | Moderate |
| Oct | 2 in | 4 days | 2.3 in | High |
| Nov | 1.3 in | 3 days | — | None |
| Dec | 1 in | 4 days | — | None |
Annual total: 34.4 in. Water needs vary by crop — tomatoes need ~1.2"/week while herbs like rosemary need only 0.3"/week. Check individual plant pages for crop-specific water budgets that factor in your county's rainfall and soil drainage.
Harmon County Soil Profile
Soil Type
Loam
Soil pH
6.5-7.5
Drainage
Well Drained
Frost Risk Probability
Based on 31 years of NOAA weather station data from 3 stations
Beginners: Plant frost-sensitive crops (tomatoes, peppers, squash) after the "Safe" date on the left. Harvest or cover them before the "Protect by" date on the right. Hardy crops (lettuce, peas, kale) can go in the yellow transition zones.
How to read this table: "Conservative" means you're safe from frost 9 out of 10 years — best for beginners and frost-sensitive crops. "Average year" is the typical date. "Aggressive" means only 1 in 10 years is that warm — experienced gardeners with frost protection can try these dates.
| Planting Strategy | Last Spring Frost | First Fall Frost | Frost-Free Days |
|---|---|---|---|
| Conservative (safest) | Apr 15 | Nov 20 | 219 days |
| Cautious | Apr 8 | Nov 12 | 218 days |
| Average year | Mar 31 | Nov 5 | 219 days |
| Optimistic | Mar 23 | Oct 28 | 219 days |
| Aggressive (risky) | Mar 14 | Oct 23 | 223 days |
Not very — frost dates can vary by ±32 days year-to-year. Use the "Conservative" row in the table below, and keep row covers handy for surprise late frosts.
Gardening Difficulty Score
Harmon County offers good growing conditions. A little planning around frost dates goes a long way.
Local Gardening Help in Harmon County
Free expert help is closer than you think. Your county's cooperative extension office connects you with trained gardeners, soil testing labs, and local programs — all specific to Harmon County's climate and soil.
County Extension Office
Harmon County Oklahoma State University Extension Extension Office
Phone: 405-744-5398
Visit Extension Office Website →
Extension offices are run by land-grant universities and funded by the USDA. Their advice is free, research-based, and tailored to your county's specific conditions.
Master Gardener Program
Free gardening help from trained volunteers
Master Gardeners are community volunteers who complete 40–60 hours of university horticultural training. They answer gardening questions, diagnose plant problems, and offer workshops — all free.
Many extension offices run a Master Gardener hotline where you can call or email with photos of plant problems for free diagnosis.
Soil Testing
Available through your extension office
Before amending your soil, get it tested. Your extension office offers soil testing (typically $10–$25) that tells you exact pH, nutrient levels, and amendment recommendations specific to what you want to grow.
Services Available in Harmon County
Finding local nurseries & garden centers in Harmon County
Why Buy Local
Local nurseries carry plants that are proven to grow in your area. Staff can give you advice specific to Harmon County's soil and climate that big-box stores can't. Plants from local growers are typically hardier because they're already acclimated to your zone.
How to Find Them
Search for "nurseries near Harmon County OK" or "garden center Harmon County" on Google Maps. Also check with your extension office — they often maintain lists of reputable local nurseries and plant sales.
Community gardens & gardening groups
Community gardens are a great way to learn from experienced gardeners in your area, especially if you're limited on space. Search "community garden Harmon County OK" or check your extension office and local parks department. Facebook groups like "Harmon County Gardeners" or "Oklahoma Gardening" are also excellent for local advice and plant swaps.
What to Plant After Your Harvest
After your first crops finish, use the remaining frost-free days to grow a second round.
Show 6 more succession options
Sunlight & Day Length
Monthly daylight hours and peak sun — critical for onion varieties, photoperiod-sensitive plants, and solar garden planning.
Longest Day
14.3 hours
Summer solstice daylight
Shortest Day
9.7 hours
Winter solstice daylight
Peak Sun Hours
10.1 hr/day peak (summer)
Peak sun hours (green dashed line below) account for cloud cover — this is the usable direct sunlight your garden actually receives. Most vegetables need 6+ peak sun hours.
Onion tip: Day-neutral onion varieties like Candy, Cabernet, and Sierra Blanca perform best in your day-length range.
View detailed monthly data
| Month | Daylight Hours | Peak Sun Hours | Day Length |
|---|---|---|---|
| January | 9.9 hr | 5.4 hr | Short day |
| February | 10.7 hr | 6.2 hr | Short day |
| March | 11.7 hr | 6.9 hr | Short day |
| April | 12.9 hr | 8.2 hr | Neutral |
| May | 13.8 hr | 8.6 hr | Neutral |
| June | 14.3 hr | 10.1 hr | Long day |
| July | 14.1 hr | 10.1 hr | Long day |
| August | 13.3 hr | 9.2 hr | Neutral |
| September | 12.2 hr | 8.2 hr | Neutral |
| October | 11.1 hr | 7.1 hr | Short day |
| November | 10.1 hr | 5.6 hr | Short day |
| December | 9.7 hr | 5.5 hr | Short day |
Peak sun hours factor in typical cloud cover — use these for solar panel and shade-planning calculations.
Soil Temperature & Composting Calendar
Monthly soil temps tell you when to plant warm-season crops, and when your compost pile is actively working.
Plant Warm Crops When
Soil reaches 60°F+
Soil warm enough from May through Oct.
Best Month to Compost
May
Microbial activity peaks when soil is warm.
Active Composting
8 months
Nearly year-round composting.
View detailed monthly data
| Month | Soil 4" Deep | Soil 8" Deep | Compost Activity | Time to Finish |
|---|---|---|---|---|
| Jan | 39°F | 46°F | ❄️ Dormant | ~36 weeks |
| Feb | 38°F | 45°F | ❄️ Dormant | ~36 weeks |
| Mar | 47°F | 50°F | 🐢 Slow | ~24 weeks |
| Apr | 57°F | 57°F | ♻️ Active | ~14 weeks |
| May | 68°F | 65°F | 🔥 Peak | ~8 weeks |
| Jun | 76°F | 75°F | 🔥 Peak | ~8 weeks |
| Jul | 85°F | 81°F | 🔥 Peak | ~8 weeks |
| Aug | 89°F | 84°F | 🔥 Peak | ~8 weeks |
| Sep | 80°F | 80°F | 🔥 Peak | ~8 weeks |
| Oct | 68°F | 71°F | 🔥 Peak | ~8 weeks |
| Nov | 57°F | 61°F | ♻️ Active | ~14 weeks |
| Dec | 45°F | 52°F | 🐢 Slow | ~24 weeks |
Highlighted rows = soil 60°F+ (safe for warm-season transplants). Compost finishes fastest during peak activity months.
Pest & Disease Pressure in Harmon County
Computed from local climate patterns — warmer, humid conditions increase pest generations and fungal disease risk.
Insect Pest Pressure
Moderate — common pests appear but manageable with monitoring.
Disease Risk
Low disease risk — dry conditions reduce fungal problems.
Seasonal Risk
View 6 common pests in your area
| Pest | Risk Level | Peak Months |
|---|---|---|
| Aphids | Moderate | Mar, Apr, May, Jun, Jul, Aug, Sep, Oct |
| Japanese beetles | Moderate | Jun, Jul, Aug |
| Squash vine borers | High | May, Jun, Jul |
| Stink bugs | High | May, Jun, Jul, Aug, Sep |
| Whiteflies | Low | Jun, Jul, Aug, Sep |
| Spider mites | Moderate | Jul, Aug |
Organic pest management tips
- Use row covers on susceptible crops during peak pest months
- Apply neem oil preventatively every 7-14 days during active pest season
- Interplant with strong-scented herbs (basil, marigold) to confuse pests
- Hand-pick larger pests (beetles, caterpillars) in early morning when they're sluggish
- Practice crop rotation — never plant the same family in the same spot within 3 years
Cover Crops for Harmon County
Cover crops protect bare soil, fix nitrogen, suppress weeds, and improve soil structure — with county-specific planting dates.
Spring Cover Crops (4 options) — Build soil before the main growing season
| Crop | Plant By | Terminate | N-Fixing | Soil Benefit |
|---|---|---|---|---|
| Buckwheat | Apr 6 | Sep 10 | — | Rapid growth, attracts pollinators, suppresses weeds |
| Cowpeas (southern peas) | Apr 6 | Sep 3 | ✓ Yes | Excellent nitrogen fixer for warm climates, edible |
| Sorghum-sudan grass | Apr 7 | Sep 10 | — | Massive biomass, breaks compaction, suppresses nematodes |
| White clover | Mar 2 | Sep 3 | ✓ Yes | Living mulch, fixes nitrogen, permanent ground cover |
Summer Cover Crops (1 options) — Fill gaps and suppress weeds between plantings
| Crop | Plant By | Terminate | N-Fixing | Soil Benefit |
|---|---|---|---|---|
| Sunflowers | Apr 25 | Oct 22 | — | Deep roots break compaction, attract pollinators and beneficial insects |
Fall Cover Crops (7 options) — Plant after harvest to protect soil over winter
| Crop | Plant By | Terminate | N-Fixing | Soil Benefit |
|---|---|---|---|---|
| Austrian winter peas | Sep 4 | Mar 10 | ✓ Yes | Fixes nitrogen, good for heavy clay soils |
| Crimson clover | Sep 11 | Mar 10 | ✓ Yes | Fixes nitrogen, attracts pollinators in spring |
| Daikon radish | Sep 14 | Mar 17 | — | Deep taproot breaks compaction, excellent for clay soils |
| Hairy vetch | Aug 21 | Mar 10 | ✓ Yes | Excellent nitrogen fixer, good for depleted soils |
| Oats | Sep 22 | Mar 10 | — | Quick biomass, winterkills in cold zones — no spring tillage needed |
| Winter rye | Aug 4 | Mar 17 | — | Suppresses weeds, prevents erosion, breaks up compacted soil |
| Winter wheat | Aug 4 | Mar 10 | — | Erosion control, weed suppression, good biomass |
Wind & Microclimate
Wind dries soil, stresses plants, and affects frost patterns. Understanding your exposure helps with garden placement.
Seasonal Wind Speed
Spring: 16 mph Summer: 12 mph
Fall: 13 mph Winter: 16 mph
Prevailing wind: S. Windy area — plant a windbreak hedge on the S side of your garden.
Windbreak Benefit
9.1/10
Strongly recommended — a windbreak (fence, hedge, or row of tall crops like corn or sunflowers) will significantly improve garden yields.
Frost Pocket Risk
Low
Relatively flat terrain (378 ft range). Frost pocket risk is minimal — garden placement is flexible.
Rainwater Harvesting Potential
How much water you can collect, when to collect it, and what size system you need for your garden.
Annual Collection
17,144 gal
Per 1,000 sq ft of roof area (at 80% collection efficiency)
Recommended Setup
6 rain barrels (55 gal each)
For a typical 500 sq ft garden. Serious collectors: consider a 1,000 gal tank.
Legal Status
Unrestricted
Rainwater harvesting is fully legal in your state with no restrictions.
Best Collection Months
May, Jun, Jul, Aug
Highest rainfall months — your barrels will fill up quickly during these months.
Months to Draw From Storage
Jan
Dry months when you'll rely on stored water — size your storage for this gap.
Rainwater collection tips for your area
- Your county receives approximately 34.4 inches of rain per year
- A 1,000 sq ft roof can collect roughly 17,144 gallons annually
- Rainwater harvesting is fully legal in your state
- Use a first-flush diverter to keep roof debris out of your collection
Soil & Growing Conditions in Harmon County
Soil Type
Loam
Soil pH 6.5–7.5 · Well Drained drainage
Native soil is well-suited to most vegetables and herbs with regular compost additions.
Watering Needs
Drought stress: 7.5/10
High drought stress. Consistent irrigation is essential — consider drip systems, heavy mulch, and drought-tolerant varieties.
Season Tips
219-day frost-free season
Plenty of time for warm-season crops. Start heat-lovers indoors 6–8 weeks before last frost to maximise your harvest window.
Free Garden Planner
Plan your entire garden season — organize planting dates, track what you're growing, and know exactly when to start seeds, transplant, and harvest.
Recommended for Your Garden
Test your soil pH, nitrogen, phosphorus, and potassium levels before planting.
Get instant, accurate soil pH readings to fine-tune your amendments.
Boost soil fertility and structure with rich, well-aged organic compost.
🥬 Vegetables to Grow in Harmon County
113 vegetables that grow well in Zone 7b with planting dates for Harmon County.
Show all 113 vegetables with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Harvest | Days to Maturity |
|---|---|---|---|---|---|
| Acorn Squash | Mar 3 | Apr 7 | Apr 14 | Jul 7 – Aug 11 | 80–100 |
| Amaranth | Feb 10 | Apr 7 | Apr 14 | Jul 14 – Sep 1 | 90–120 |
| Artichoke | — | — | Apr 14 | Aug 18 – Oct 27 | 120–180 |
| Arugula | Feb 24 | Mar 17 | Mar 31 | May 5 – Jul 7 | 30–50 |
| Asparagus | — | — | Apr 14 | — | 730–1095 |
| Beets | — | Mar 17 | — | May 12 – Jun 9 | 50–70 |
| Belgian Endive | Feb 24 | Mar 17 | Mar 31 | Jul 21 – Sep 15 | 110–150 |
| Bitter Melon | Feb 10 | Apr 7 | Apr 14 | Jun 16 – Jul 28 | 60–90 |
| Black Beans | — | Apr 7 | — | Jul 7 – Aug 25 | 90–120 |
| Bok Choy | Feb 24 | Mar 17 | Mar 31 | May 12 – Jun 16 | 40–60 |
| Broccoli | Feb 24 | Mar 17 | Mar 31 | Jun 2 – Jul 14 | 60–90 |
| Broccoli Rabe | Feb 24 | Mar 17 | Mar 31 | May 12 – Jun 16 | 40–60 |
| Brussels Sprouts | Feb 24 | Mar 17 | Mar 31 | Jun 30 – Aug 25 | 90–130 |
| Butternut Squash | Mar 3 | Apr 7 | Apr 14 | Jul 14 – Aug 18 | 85–110 |
| Cabbage | Feb 24 | Mar 17 | Mar 31 | Jun 2 – Jul 28 | 60–100 |
| Calabash | Feb 10 | Apr 7 | Apr 14 | Jul 7 – Sep 1 | 80–120 |
| Cardoon | — | — | Apr 14 | Aug 18 – Sep 29 | 120–150 |
| Carrots | — | Mar 17 | — | May 19 – Jun 23 | 60–80 |
| Cauliflower | Feb 24 | Mar 17 | Mar 31 | May 26 – Jul 28 | 55–100 |
| Celeriac | Feb 24 | Mar 17 | Mar 31 | Jul 14 – Aug 18 | 100–120 |
| Celery | Feb 24 | Mar 17 | Mar 31 | Jun 23 – Aug 18 | 80–120 |
| Celtuce | Feb 24 | Mar 17 | Mar 31 | Jun 2 – Jul 14 | 60–90 |
| Chard | Feb 24 | Mar 17 | Mar 31 | May 26 – Jul 14 | 50–60 |
| Chayote | Feb 10 | Apr 7 | Apr 14 | Aug 18 – Oct 27 | 120–180 |
| Chickpeas | Feb 24 | Mar 17 | Mar 31 | Jun 23 – Aug 4 | 80–110 |
| Chicory | Feb 24 | Mar 17 | Mar 31 | Jun 2 – Jul 14 | 60–85 |
| Chinese Cabbage | Feb 24 | Mar 17 | Mar 31 | May 26 – Jun 23 | 50–70 |
| Christmas Lima Beans | Feb 10 | Apr 7 | Apr 14 | Jul 7 – Aug 11 | 80–100 |
| Collard Greens | Feb 24 | Mar 17 | Mar 31 | May 26 – Jul 28 | 55–75 |
| Corn | — | Apr 7 | — | Jun 9 – Aug 4 | 60–100 |
| Cowpeas | — | Apr 7 | — | Jun 9 – Jul 21 | 60–90 |
| Cress | Feb 24 | Mar 17 | Mar 31 | Apr 14 – May 5 | 14–21 |
| Crookneck Squash | Mar 3 | Apr 7 | Apr 14 | Jun 2 – Jun 30 | 45–60 |
| Crosne | — | Mar 17 | — | Aug 18 – Oct 20 | 150–200 |
| Cucumber | Mar 3 | Apr 7 | Apr 14 | Jun 9 – Aug 4 | 50–70 |
| Daikon | — | Mar 17 | — | May 12 – Jun 9 | 50–70 |
| Delicata Squash | Mar 3 | Apr 7 | Apr 14 | Jul 7 – Aug 11 | 80–100 |
| Edamame | — | Apr 7 | — | Jun 23 – Aug 4 | 75–100 |
| Eggplant | Jan 27 | Apr 7 | Apr 14 | Jun 23 – Aug 25 | 65–85 |
| Endive | Feb 24 | Mar 17 | Mar 31 | May 19 – Jun 23 | 45–65 |
| Escarole | Feb 24 | Mar 17 | Mar 31 | May 26 – Jun 23 | 50–70 |
| Fava Beans | Feb 24 | Mar 17 | Mar 31 | Jun 16 – Jul 28 | 75–100 |
| Fennel | Feb 10 | Apr 7 | Apr 14 | Jun 16 – Jul 28 | 60–90 |
| Garlic | — | — | — | — | 90–240 |
| Green Beans | — | Apr 7 | — | Jun 2 – Jul 28 | 50–65 |
| Horseradish | — | — | Apr 14 | Aug 18 – Oct 27 | 120–180 |
| Hot Peppers | Jan 27 | Apr 7 | Apr 14 | Jun 23 – Sep 29 | 70–120 |
| Hubbard Squash | Mar 3 | Apr 7 | Apr 14 | Jul 28 – Sep 1 | 100–120 |
| Jicama | Feb 10 | Apr 7 | Apr 14 | Aug 18 – Oct 27 | 120–180 |
| Kabocha | Mar 3 | Apr 7 | Apr 14 | Jul 14 – Aug 11 | 85–100 |
| Kai Lan | Feb 24 | Mar 17 | Mar 31 | May 19 – Jun 16 | 45–60 |
| Kale | Feb 24 | Mar 17 | Mar 31 | May 26 – Jul 21 | 50–70 |
| Kidney Beans | — | Apr 7 | — | Jul 7 – Aug 11 | 85–110 |
| Kohlrabi | Feb 24 | Mar 17 | Mar 31 | May 19 – Jun 23 | 45–65 |
| Komatsuna | Feb 24 | Mar 17 | Mar 31 | May 5 – Jun 9 | 35–50 |
| Leeks | Feb 24 | Mar 17 | Mar 31 | Jun 30 – Sep 15 | 90–150 |
| Lentils | Feb 24 | Mar 17 | Mar 31 | Jun 23 – Aug 4 | 80–110 |
| Lettuce | Feb 24 | Mar 17 | Mar 31 | May 5 – Jul 14 | 30–60 |
| Lima Beans | — | Apr 7 | — | Jun 9 – Jul 21 | 60–90 |
| Loofah | Feb 10 | Apr 7 | Apr 14 | Jul 28 – Sep 29 | 100–150 |
| Luffa | Feb 10 | Apr 7 | Apr 14 | Jul 14 – Sep 29 | 90–150 |
| Mache | Feb 24 | Mar 17 | Mar 31 | May 12 – Jun 16 | 40–60 |
| Malabar Spinach | Feb 10 | Apr 7 | Apr 14 | Jun 9 – Jul 7 | 55–70 |
| Melon | Mar 3 | Apr 7 | Apr 14 | Jun 23 – Aug 11 | 70–100 |
| Microgreens | Feb 24 | Mar 17 | Mar 31 | Apr 7 – May 5 | 7–21 |
| Mitsuba | Feb 24 | Mar 17 | Mar 24 | May 19 – Jul 14 | 50–70 |
| Mizuna | Feb 24 | Mar 17 | Mar 31 | May 5 – Jun 2 | 30–45 |
| Mustard Greens | Feb 24 | Mar 17 | Mar 31 | May 5 – Jul 7 | 30–50 |
| Napa Cabbage | Feb 24 | Mar 17 | Mar 31 | May 26 – Jun 30 | 55–75 |
| New Zealand Spinach | Feb 10 | Apr 7 | Apr 14 | Jun 9 – Jul 7 | 55–70 |
| Okra | Feb 10 | Apr 7 | Apr 14 | Jun 9 – Aug 4 | 50–65 |
| Onion | Feb 24 | Mar 17 | Mar 31 | Jun 30 – Aug 18 | 90–120 |
| Pac Choi | Feb 24 | Mar 17 | Mar 31 | May 12 – Jun 9 | 40–55 |
| Parsnip | — | Mar 17 | — | Jun 30 – Aug 11 | 100–130 |
| Patty Pan Squash | Mar 3 | Apr 7 | Apr 14 | Jun 2 – Jun 30 | 45–60 |
| Peas | Feb 24 | Mar 17 | Mar 31 | May 26 – Jul 21 | 55–70 |
| Peppers | Jan 27 | Apr 7 | Apr 14 | Jun 16 – Aug 25 | 60–90 |
| Pole Beans | Feb 10 | Apr 7 | Apr 14 | Jun 9 – Aug 4 | 55–70 |
| Potatoes | Feb 10 | Apr 7 | Apr 14 | Jun 23 – Sep 1 | 70–120 |
| Pumpkin | Mar 3 | Apr 7 | Apr 14 | Jul 14 – Sep 1 | 85–120 |
| Purslane | Feb 24 | Mar 17 | Mar 31 | May 12 – Jun 16 | 40–60 |
| Radicchio | Feb 24 | Mar 17 | Mar 31 | Jun 2 – Jul 7 | 60–80 |
| Radish | — | Mar 17 | — | Apr 14 – May 5 | 22–35 |
| Rhubarb | — | — | Apr 21 | — | 365–730 |
| Romanesco | Feb 24 | Mar 17 | Mar 31 | Jun 16 – Jul 28 | 75–100 |
| Rutabaga | — | Mar 17 | — | Jun 9 – Jul 14 | 80–100 |
| Salsify | — | Mar 17 | — | Jun 30 – Aug 11 | 100–130 |
| Savoy Cabbage | Feb 24 | Mar 17 | Mar 31 | Jun 9 – Aug 4 | 70–110 |
| Scallions | Feb 24 | Mar 17 | Mar 31 | May 26 – Jun 23 | 50–70 |
| Scarlet Runner Beans | Feb 10 | Apr 7 | Apr 14 | Jun 16 – Jul 21 | 60–80 |
| Shallot | Feb 24 | Mar 17 | Mar 31 | Jun 30 – Aug 18 | 90–120 |
| Shiso | Feb 10 | Apr 7 | Apr 14 | Jun 9 – Aug 4 | 50–70 |
| Snap Peas | Feb 10 | Apr 7 | Apr 14 | Jun 9 – Aug 4 | 55–70 |
| Snow Peas | Feb 24 | Mar 17 | Mar 31 | May 26 – Jul 21 | 50–65 |
| Soybeans | — | Apr 7 | — | Jun 30 – Aug 25 | 80–120 |
| Spaghetti Squash | Mar 3 | Apr 7 | Apr 14 | Jul 14 – Aug 11 | 85–100 |
| Spinach | Feb 24 | Mar 17 | Mar 31 | May 5 – Jul 7 | 35–50 |
| Squash (Summer) | Mar 3 | Apr 7 | Apr 14 | Jun 2 – Aug 4 | 45–65 |
| Squash (Winter) | Mar 3 | Apr 7 | Apr 14 | Jul 7 – Sep 1 | 80–120 |
| Sunchoke | — | — | Apr 14 | Aug 4 – Sep 29 | 110–150 |
| Sunflower | Feb 10 | Apr 7 | Apr 14 | Jun 23 – Aug 11 | 70–100 |
| Sweet Corn | — | Apr 7 | — | Jun 9 – Jul 21 | 60–90 |
| Sweet Potatoes | Feb 10 | Apr 7 | Apr 14 | Jul 14 – Sep 1 | 90–120 |
| Tatsoi | Feb 24 | Mar 17 | Mar 31 | May 5 – Jun 9 | 35–50 |
| Tomatillo | Feb 10 | Apr 7 | Apr 14 | Jun 16 – Aug 25 | 60–85 |
| Tomatoes | Feb 10 | Apr 7 | Apr 14 | Jun 16 – Aug 25 | 60–85 |
| Turnip | — | Mar 17 | — | Apr 28 – Jun 2 | 40–60 |
| Watercress | Feb 24 | Mar 17 | Mar 31 | May 12 – Jun 16 | 40–60 |
| Watermelon | Mar 3 | Apr 7 | Apr 14 | Jun 23 – Aug 11 | 70–100 |
| Wax Beans | — | Apr 7 | — | Jun 2 – Jul 28 | 50–65 |
| Winter Melon | Feb 10 | Apr 7 | Apr 14 | Jul 14 – Sep 1 | 90–120 |
| Yard Long Beans | Feb 10 | Apr 7 | Apr 14 | Jun 9 – Jul 21 | 55–80 |
| Zucchini | Mar 3 | Apr 7 | Apr 14 | Jun 2 – Jul 28 | 45–60 |
🍓 Fruits to Grow in Harmon County
31 fruits that grow well in Zone 7b with planting dates for Harmon County.
Show all 31 fruits with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Harvest | Days to Maturity |
|---|---|---|---|---|---|
| Alpine Strawberries | — | — | Apr 21 | Jul 21 – Nov 3 | 90–180 |
| Aronia | — | — | Apr 21 | — | 730–1095 |
| Blackberries | — | — | Apr 21 | — | 365–730 |
| Blueberries | — | — | Apr 21 | — | 730–1095 |
| Boysenberries | — | — | Apr 21 | — | 365–730 |
| Cantaloupe | — | — | Apr 21 | Jun 30 – Aug 4 | 70–90 |
| Che Fruit | — | — | Apr 21 | — | 1095–1825 |
| Cranberries | — | — | Apr 21 | — | 730–1095 |
| Currants | — | — | Apr 21 | — | 730–1095 |
| Elderberries | — | — | Apr 21 | — | 730–1095 |
| Figs | — | — | Apr 21 | — | 730–1825 |
| Goji Berries | — | — | Apr 21 | — | 730–1095 |
| Gooseberries | — | — | Apr 21 | — | 730–1095 |
| Grapes | — | — | Apr 21 | — | 730–1095 |
| Ground Cherry | — | — | Apr 21 | Jun 30 – Aug 25 | 65–80 |
| Hardy Kiwi | — | — | Apr 21 | — | 1095–1825 |
| Haskaps | — | — | Apr 21 | — | 730–1095 |
| Honeydew | — | — | Apr 21 | Jul 14 – Aug 25 | 80–110 |
| Jostaberry | — | — | Apr 21 | — | 730–1095 |
| Kiwi | — | — | Apr 21 | — | 1095–1825 |
| Lingonberries | — | — | Apr 21 | — | 730–1095 |
| Loquat | — | — | Apr 21 | — | 730–1825 |
| Medlar | — | — | Apr 21 | — | 1095–1825 |
| Mulberries | — | — | Apr 21 | — | 730–1825 |
| Pawpaw | — | — | Apr 21 | — | 1095–2555 |
| Persimmon | — | — | Apr 21 | — | 1095–2555 |
| Pomegranate | — | — | Apr 21 | — | 730–1095 |
| Quince | — | — | Apr 21 | — | 1095–1825 |
| Raspberries | — | — | Apr 21 | — | 365–730 |
| Serviceberries | — | — | Apr 21 | — | 730–1095 |
| Strawberries | — | — | Apr 21 | Jul 21 – Dec 1 | 90–365 |
🌿 Herbs to Grow in Harmon County
39 herbs that grow well in Zone 7b with planting dates for Harmon County.
Show all 39 herbs with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Harvest | Days to Maturity |
|---|---|---|---|---|---|
| Angelica | Feb 24 | Mar 17 | Mar 24 | — | 365–730 |
| Anise | Feb 24 | Mar 17 | Mar 24 | Jun 23 – Sep 8 | 90–120 |
| Basil | Feb 10 | Apr 7 | Apr 14 | Jun 9 – Aug 11 | 50–75 |
| Bee Balm | — | — | Apr 7 | Jul 7 – Sep 22 | 90–120 |
| Borage | Feb 24 | Mar 17 | Mar 24 | May 19 – Jul 7 | 50–60 |
| Caraway | Feb 24 | Mar 17 | Mar 24 | — | 365–450 |
| Catnip | — | — | Apr 7 | Jun 9 – Aug 11 | 60–80 |
| Chamomile | Feb 24 | Mar 17 | Mar 24 | May 26 – Aug 4 | 60–90 |
| Chervil | Feb 24 | Mar 17 | Mar 24 | May 5 – Jul 7 | 40–60 |
| Chives | — | — | Apr 7 | Jun 9 – Aug 18 | 60–90 |
| Cilantro | Feb 24 | Mar 17 | Mar 24 | May 5 – Jul 7 | 40–60 |
| Comfrey | — | — | Apr 7 | Jun 9 – Aug 18 | 60–90 |
| Cumin | Feb 24 | Mar 17 | Mar 24 | Jul 7 – Sep 8 | 100–120 |
| Dill | Feb 24 | Mar 17 | Mar 24 | May 5 – Jul 7 | 40–60 |
| Echinacea | — | — | Apr 7 | Aug 11 – Nov 17 | 120–180 |
| Epazote | Feb 10 | Apr 7 | Apr 14 | Jun 2 – Jul 28 | 45–60 |
| Fennel (herb) | Feb 24 | Mar 17 | Mar 24 | May 26 – Aug 4 | 60–90 |
| Feverfew | — | — | Apr 7 | Jul 7 – Sep 22 | 90–120 |
| Garlic Chives | — | — | Apr 7 | Jun 9 – Aug 18 | 60–90 |
| Horehound | — | — | Apr 7 | Jun 23 – Aug 18 | 75–90 |
| Hyssop | — | — | Apr 7 | Jun 16 – Aug 18 | 70–90 |
| Lavender | — | — | Apr 7 | Jul 7 – Nov 17 | 90–200 |
| Lemon Balm | — | — | Apr 7 | Jun 9 – Jul 28 | 60–70 |
| Lemon Thyme | — | — | Apr 7 | Jun 16 – Aug 18 | 70–90 |
| Lovage | — | — | Apr 7 | Jun 16 – Aug 18 | 70–90 |
| Marjoram | — | — | Apr 7 | Jun 9 – Aug 18 | 60–90 |
| Mint | — | — | Apr 7 | Jun 9 – Aug 18 | 60–90 |
| Oregano | — | — | Apr 7 | Jun 9 – Aug 18 | 60–90 |
| Parsley | Feb 24 | Mar 17 | Mar 24 | May 26 – Jul 28 | 60–80 |
| Rosemary | — | — | Apr 7 | Jun 30 – Nov 17 | 80–180 |
| Rue | — | — | Apr 7 | Jun 16 – Aug 18 | 70–90 |
| Sage | — | — | Apr 7 | Jun 23 – Aug 18 | 75–90 |
| Savory | — | — | Apr 7 | Jun 2 – Jul 28 | 50–70 |
| Sorrel | Feb 24 | Mar 17 | Mar 24 | May 5 – Jul 7 | 40–60 |
| Tarragon | — | — | Apr 7 | Jun 9 – Aug 18 | 60–90 |
| Thai Basil | Feb 10 | Apr 7 | Apr 14 | Jun 9 – Aug 11 | 50–75 |
| Thyme | — | — | Apr 7 | Jun 16 – Aug 18 | 70–90 |
| Valerian | — | — | Apr 7 | Aug 11 – Nov 17 | 120–180 |
| Yarrow | — | — | Apr 7 | Jul 7 – Sep 22 | 90–120 |
Monthly Planting Guide for Harmon County
Gardening Guides & Resources
Helpful guides from The Ultimate Homestead to improve your garden in Harmon County.
Frequently Asked Questions
What planting zone is Harmon County, OK?
Harmon County is in USDA Hardiness Zone 7b. This zone classification determines which perennial plants survive winter and sets the baseline for frost timing across the county.
When is the last frost in Harmon County, OK?
Based on 31 years of NOAA weather station data, the median last spring frost in Harmon County falls around March 31. In 8 out of 10 years, last frost lands between March 14 and April 15 — a 32-day window of variability. Use April 15 as your conservative safe-to-plant date for frost-sensitive crops.
When is the first fall frost in Harmon County, OK?
The median first fall frost in Harmon County arrives around November 5. In cold years it can arrive as early as October 23; in mild years as late as November 20. Harvest or protect frost-sensitive crops — tomatoes, peppers, basil, squash — before this date.
How long is the growing season in Harmon County?
Harmon County has a frost-free growing season of approximately 219 days. This long season supports multiple succession plantings and warm-season crops that need extended heat, like sweet potatoes and melons.
What is the soil like in Harmon County for gardening?
Harmon County has predominantly Loam soil with a pH range of 6.5–7.5 and Well Drained drainage. Most vegetables and herbs grow well with standard composting and seasonal soil amendment.
What is grown commercially in Harmon County?
Harmon County has commercial agriculture that includes Wheat, Cattle, Hay. These crops reflect the local climate and soil conditions — what succeeds commercially often translates well to home gardens in the same area.
Is Harmon County a good location for home gardening?
Harmon County scores 69/100 (Good) on our Microclimate Index, which combines frost reliability, drought pressure, soil challenge, elevation risk, and long-term climate trend. Conditions here are moderate — most common crops grow well with standard timing and care.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Harmon County gardeners in Zone 7b organize planting dates, track what's growing, and never miss a planting window.
Get Your Free Garden Planner →Free download. Plan your entire garden season in minutes.
