Iron County, UT — Planting Guide
Iron County is in USDA Zone 6b. The average last spring frost is May 21 and the first fall frost is October 1, giving you a growing season of approximately 133 days.
At an elevation of 6,296 ft, Iron County receives approximately 20 in of rainfall annually. Summer highs average 86°F with winter lows around 20°F. The predominant soil type is Loam.
Based on 31 years of NOAA climate station data, the last frost date here varies by 30 days year to year — ranging from May 10 in warm years to June 9 in cold years. Iron County scores 44/100 (Moderate) on the Microclimate Index.
🌡️ Zone
6b (-5°F to 0°F min)
❄️ Last Frost
May 21
🍂 First Frost
October 1
📅 Growing Season
133 days
⛰️ Elevation
6,296 ft
🌧️ Annual Rainfall
20 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 | 1.3 in | 6 days | — | None |
| Feb | 1.1 in | 5 days | — | None |
| Mar | 1.5 in | 6 days | 2.8 in | High |
| Apr | 2 in | 8 days | 2.3 in | High |
| May | 2.6 in | 9 days | 1.7 in | High |
| Jun | 1.4 in | 4 days | 2.9 in | High |
| Jul | 1.9 in | 6 days | 2.4 in | High |
| Aug | 2.2 in | 6 days | 2.1 in | High |
| Sep | 1.6 in | 5 days | 2.7 in | High |
| Oct | 1.7 in | 6 days | 2.6 in | High |
| Nov | 1.5 in | 6 days | — | None |
| Dec | 1.1 in | 6 days | — | None |
Annual total: 19.9 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.
Iron County Soil Profile
Soil Type
Loam
Soil pH
6.4-7.8
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) | Jun 9 | Oct 16 | 129 days |
| Cautious | May 29 | Oct 7 | 131 days |
| Average year | May 21 | Oct 1 | 133 days |
| Optimistic | May 13 | Sep 24 | 134 days |
| Aggressive (risky) | May 10 | Sep 17 | 130 days |
Not very — frost dates can vary by ±30 days year-to-year. Use the "Conservative" row in the table below, and keep row covers handy for surprise late frosts.
Gardening Difficulty Score
Iron County presents some gardening challenges. Choose adapted varieties and plan around frost dates.
Local Gardening Help in Iron 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 Iron County's climate and soil.
County Extension Office
Iron County Utah State University Extension Extension Office
Phone: 435-797-2200
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 Iron County
Finding local nurseries & garden centers in Iron County
Why Buy Local
Local nurseries carry plants that are proven to grow in your area. Staff can give you advice specific to Iron 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 Iron County UT" or "garden center Iron 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 Iron County UT" or check your extension office and local parks department. Facebook groups like "Iron County Gardeners" or "Utah 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
14.6 hours
Summer solstice daylight
Shortest Day
9.4 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: Your long summer days (14+ hours) support long-day onion varieties like Walla Walla, Sweet Spanish, and Ailsa Craig.
View detailed monthly data
| Month | Daylight Hours | Peak Sun Hours | Day Length |
|---|---|---|---|
| January | 9.7 hr | 5.2 hr | Short day |
| February | 10.6 hr | 6 hr | Short day |
| March | 11.7 hr | 7 hr | Short day |
| April | 13 hr | 7.4 hr | Neutral |
| May | 14 hr | 8.4 hr | Long day |
| June | 14.6 hr | 10.1 hr | Long day |
| July | 14.4 hr | 10.1 hr | Long day |
| August | 13.5 hr | 9.4 hr | Neutral |
| September | 12.2 hr | 9 hr | Neutral |
| October | 11 hr | 7.5 hr | Short day |
| November | 9.9 hr | 5.8 hr | Short day |
| December | 9.4 hr | 5.1 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 Jul through Aug.
Best Month to Compost
Aug
Microbial activity peaks when soil is warm.
Active Composting
4 months
Short season — insulate pile or use indoor vermicomposting.
View detailed monthly data
| Month | Soil 4" Deep | Soil 8" Deep | Compost Activity | Time to Finish |
|---|---|---|---|---|
| Jan | 12°F | 20°F | ❄️ Dormant | ~36 weeks |
| Feb | 13°F | 19°F | ❄️ Dormant | ~36 weeks |
| Mar | 20°F | 23°F | ❄️ Dormant | ~36 weeks |
| Apr | 33°F | 33°F | ❄️ Dormant | ~36 weeks |
| May | 47°F | 43°F | 🐢 Slow | ~24 weeks |
| Jun | 56°F | 50°F | ♻️ Active | ~14 weeks |
| Jul | 65°F | 59°F | ♻️ Active | ~14 weeks |
| Aug | 65°F | 59°F | 🔥 Peak | ~8 weeks |
| Sep | 58°F | 55°F | ♻️ Active | ~14 weeks |
| Oct | 45°F | 48°F | 🐢 Slow | ~24 weeks |
| Nov | 32°F | 37°F | ❄️ Dormant | ~36 weeks |
| Dec | 19°F | 27°F | ❄️ Dormant | ~36 weeks |
Highlighted rows = soil 60°F+ (safe for warm-season transplants). Compost finishes fastest during peak activity months.
Pest & Disease Pressure in Iron 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 | Apr, May, Jun, Jul, Aug, Sep |
| Japanese beetles | Moderate | Jun, Jul, Aug |
| Squash vine borers | Moderate | Jun, Jul |
| Tomato hornworms | Moderate | Jun, Jul, Aug |
| Cucumber beetles | Low | May, Jun, Jul |
| Stink bugs | Moderate | Jun, Jul, Aug, Sep |
Organic pest management tips
- Maintain healthy soil with regular compost additions to build natural pest resistance
- Practice crop rotation annually to break pest cycles
- Encourage beneficial insects with flowering herbs like dill, fennel, and yarrow
Cover Crops for Iron County
Cover crops protect bare soil, fix nitrogen, suppress weeds, and improve soil structure — with county-specific planting dates.
Spring Cover Crops (3 options) — Build soil before the main growing season
| Crop | Plant By | Terminate | N-Fixing | Soil Benefit |
|---|---|---|---|---|
| Buckwheat | Jun 3 | Aug 6 | — | Rapid growth, attracts pollinators, suppresses weeds |
| Sorghum-sudan grass | Jun 3 | Aug 6 | — | Massive biomass, breaks compaction, suppresses nematodes |
| White clover | Apr 25 | Aug 6 | ✓ 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 | Jun 20 | Sep 10 | — | 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 | Aug 9 | Apr 30 | ✓ Yes | Fixes nitrogen, good for heavy clay soils |
| Crimson clover | Aug 5 | May 7 | ✓ Yes | Fixes nitrogen, attracts pollinators in spring |
| Daikon radish | Aug 6 | Apr 30 | — | Deep taproot breaks compaction, excellent for clay soils |
| Hairy vetch | Jul 22 | Apr 30 | ✓ Yes | Excellent nitrogen fixer, good for depleted soils |
| Oats | Aug 30 | May 7 | — | Quick biomass, winterkills in cold zones — no spring tillage needed |
| Winter rye | Jul 9 | Apr 30 | — | Suppresses weeds, prevents erosion, breaks up compacted soil |
| Winter wheat | Jun 29 | May 7 | — | 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: 14 mph Summer: 11 mph
Fall: 12 mph Winter: 15 mph
Prevailing wind: W. Windy area — plant a windbreak hedge on the W side of your garden.
Windbreak Benefit
6.6/10
Moderately beneficial — a simple fence or trellis can protect delicate crops from wind stress.
Frost Pocket Risk
Moderate
Some terrain variation (929 ft range). Garden on slopes or higher ground if possible to avoid late-season frost pockets.
Rainwater Harvesting Potential
How much water you can collect, when to collect it, and what size system you need for your garden.
Annual Collection
9,918 gal
Per 1,000 sq ft of roof area (at 80% collection efficiency)
Recommended Setup
8 rain barrels (55 gal each)
For a typical 500 sq ft garden. Serious collectors: consider a 1,750 gal tank.
Legal Status
Limited
Your state has quantity limits on rainwater collection — check local regulations before installing large systems.
Best Collection Months
Apr, May, Jul, Aug
Highest rainfall months — your barrels will fill up quickly during these months.
Months to Draw From Storage
Jan, Feb, Dec
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 19.9 inches of rain per year
- A 1,000 sq ft roof can collect roughly 9,918 gallons annually
- Check UT state regulations — rainwater harvesting has quantity limits
- In your dry climate, every drop counts — consider a larger cistern system
- Position collection tanks in shade to reduce evaporation and algae growth
Soil & Growing Conditions in Iron County
Soil Type
Loam
Soil pH 6.4–7.8 · Well Drained drainage
Good candidate for raised beds to maximise drainage and extend the season.
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
133-day frost-free season
Start warm-season crops indoors and focus on short-season varieties. Cold frames extend your season by 3–4 weeks in fall.
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 Iron County
108 vegetables that grow well in Zone 6b with planting dates for Iron County.
Show all 108 vegetables with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Harvest | Days to Maturity |
|---|---|---|---|---|---|
| Acorn Squash | Apr 16 | May 28 | Jun 4 | Aug 27 – Oct 1 | 80–100 |
| Amaranth | Mar 26 | May 28 | Jun 4 | Sep 3 – Oct 22 | 90–120 |
| Arugula | Apr 16 | May 7 | May 21 | Jun 25 – Aug 27 | 30–50 |
| Asparagus | — | — | Jun 4 | — | 730–1095 |
| Beets | — | May 7 | — | Jul 2 – Jul 30 | 50–70 |
| Belgian Endive | Apr 16 | May 7 | May 21 | Sep 10 – Nov 5 | 110–150 |
| Bitter Melon | Mar 26 | May 28 | Jun 4 | Aug 6 – Sep 17 | 60–90 |
| Black Beans | — | May 28 | — | Aug 27 – Oct 15 | 90–120 |
| Bok Choy | Apr 16 | May 7 | May 21 | Jul 2 – Aug 6 | 40–60 |
| Broccoli | Apr 16 | May 7 | May 21 | Jul 23 – Sep 3 | 60–90 |
| Broccoli Rabe | Apr 16 | May 7 | May 21 | Jul 2 – Aug 6 | 40–60 |
| Brussels Sprouts | Apr 16 | May 7 | May 21 | Aug 20 – Oct 15 | 90–130 |
| Butternut Squash | Apr 16 | May 28 | Jun 4 | Sep 3 – Oct 8 | 85–110 |
| Cabbage | Apr 16 | May 7 | May 21 | Jul 23 – Sep 17 | 60–100 |
| Calabash | Mar 26 | May 28 | Jun 4 | Aug 27 – Oct 22 | 80–120 |
| Carrots | — | May 7 | — | Jul 9 – Aug 13 | 60–80 |
| Cauliflower | Apr 16 | May 7 | May 21 | Jul 16 – Sep 17 | 55–100 |
| Celeriac | Apr 16 | May 7 | May 21 | Sep 3 – Oct 8 | 100–120 |
| Celery | Apr 16 | May 7 | May 21 | Aug 13 – Oct 8 | 80–120 |
| Celtuce | Apr 16 | May 7 | May 21 | Jul 23 – Sep 3 | 60–90 |
| Chard | Apr 16 | May 7 | May 21 | Jul 16 – Sep 3 | 50–60 |
| Chickpeas | Apr 16 | May 7 | May 21 | Aug 13 – Sep 24 | 80–110 |
| Chicory | Apr 16 | May 7 | May 21 | Jul 23 – Sep 3 | 60–85 |
| Chinese Cabbage | Apr 16 | May 7 | May 21 | Jul 16 – Aug 13 | 50–70 |
| Christmas Lima Beans | Mar 26 | May 28 | Jun 4 | Aug 27 – Oct 1 | 80–100 |
| Collard Greens | Apr 16 | May 7 | May 21 | Jul 16 – Sep 17 | 55–75 |
| Corn | — | May 28 | — | Jul 30 – Sep 24 | 60–100 |
| Cowpeas | — | May 28 | — | Jul 30 – Sep 10 | 60–90 |
| Cress | Apr 16 | May 7 | May 21 | Jun 4 – Jun 25 | 14–21 |
| Crookneck Squash | Apr 16 | May 28 | Jun 4 | Jul 23 – Aug 20 | 45–60 |
| Crosne | — | May 7 | — | Oct 8 – Nov 19 | 150–200 |
| Cucumber | Apr 16 | May 28 | Jun 4 | Jul 30 – Sep 24 | 50–70 |
| Daikon | — | May 7 | — | Jul 2 – Jul 30 | 50–70 |
| Delicata Squash | Apr 16 | May 28 | Jun 4 | Aug 27 – Oct 1 | 80–100 |
| Edamame | — | May 28 | — | Aug 13 – Sep 24 | 75–100 |
| Eggplant | Mar 12 | May 28 | Jun 4 | Aug 13 – Oct 15 | 65–85 |
| Endive | Apr 16 | May 7 | May 21 | Jul 9 – Aug 13 | 45–65 |
| Escarole | Apr 16 | May 7 | May 21 | Jul 16 – Aug 13 | 50–70 |
| Fava Beans | Apr 16 | May 7 | May 21 | Aug 6 – Sep 17 | 75–100 |
| Fennel | Mar 26 | May 28 | Jun 4 | Aug 6 – Sep 17 | 60–90 |
| Garlic | — | — | — | — | 90–240 |
| Green Beans | — | May 28 | — | Jul 23 – Sep 17 | 50–65 |
| Horseradish | — | — | Jun 4 | Oct 8 – Dec 17 | 120–180 |
| Hot Peppers | Mar 12 | May 28 | Jun 4 | Aug 13 – Nov 19 | 70–120 |
| Hubbard Squash | Apr 16 | May 28 | Jun 4 | Sep 17 – Oct 22 | 100–120 |
| Kabocha | Apr 16 | May 28 | Jun 4 | Sep 3 – Oct 1 | 85–100 |
| Kai Lan | Apr 16 | May 7 | May 21 | Jul 9 – Aug 6 | 45–60 |
| Kale | Apr 16 | May 7 | May 21 | Jul 16 – Sep 10 | 50–70 |
| Kidney Beans | — | May 28 | — | Aug 27 – Oct 1 | 85–110 |
| Kohlrabi | Apr 16 | May 7 | May 21 | Jul 9 – Aug 13 | 45–65 |
| Komatsuna | Apr 16 | May 7 | May 21 | Jun 25 – Jul 30 | 35–50 |
| Leeks | Apr 16 | May 7 | May 21 | Aug 20 – Nov 5 | 90–150 |
| Lentils | Apr 16 | May 7 | May 21 | Aug 13 – Sep 24 | 80–110 |
| Lettuce | Apr 16 | May 7 | May 21 | Jun 25 – Sep 3 | 30–60 |
| Lima Beans | — | May 28 | — | Jul 30 – Sep 10 | 60–90 |
| Loofah | Mar 26 | May 28 | Jun 4 | Sep 17 – Nov 19 | 100–150 |
| Luffa | Mar 26 | May 28 | Jun 4 | Sep 3 – Nov 19 | 90–150 |
| Mache | Apr 16 | May 7 | May 21 | Jul 2 – Aug 6 | 40–60 |
| Melon | Apr 16 | May 28 | Jun 4 | Aug 13 – Oct 1 | 70–100 |
| Microgreens | Apr 16 | May 7 | May 21 | May 28 – Jun 25 | 7–21 |
| Mitsuba | Apr 16 | May 7 | May 14 | Jul 9 – Sep 3 | 50–70 |
| Mizuna | Apr 16 | May 7 | May 21 | Jun 25 – Jul 23 | 30–45 |
| Mustard Greens | Apr 16 | May 7 | May 21 | Jun 25 – Aug 27 | 30–50 |
| Napa Cabbage | Apr 16 | May 7 | May 21 | Jul 16 – Aug 20 | 55–75 |
| New Zealand Spinach | Mar 26 | May 28 | Jun 4 | Jul 30 – Aug 27 | 55–70 |
| Okra | Mar 26 | May 28 | Jun 4 | Jul 30 – Sep 24 | 50–65 |
| Onion | Apr 16 | May 7 | May 21 | Aug 20 – Oct 8 | 90–120 |
| Pac Choi | Apr 16 | May 7 | May 21 | Jul 2 – Jul 30 | 40–55 |
| Parsnip | — | May 7 | — | Aug 20 – Oct 1 | 100–130 |
| Patty Pan Squash | Apr 16 | May 28 | Jun 4 | Jul 23 – Aug 20 | 45–60 |
| Peas | Apr 16 | May 7 | May 21 | Jul 16 – Sep 10 | 55–70 |
| Peppers | Mar 12 | May 28 | Jun 4 | Aug 6 – Oct 15 | 60–90 |
| Pole Beans | Mar 26 | May 28 | Jun 4 | Jul 30 – Sep 24 | 55–70 |
| Potatoes | Mar 26 | May 28 | Jun 4 | Aug 13 – Oct 22 | 70–120 |
| Pumpkin | Apr 16 | May 28 | Jun 4 | Sep 3 – Oct 22 | 85–120 |
| Purslane | Apr 16 | May 7 | May 21 | Jul 2 – Aug 6 | 40–60 |
| Radicchio | Apr 16 | May 7 | May 21 | Jul 23 – Aug 27 | 60–80 |
| Radish | — | May 7 | — | Jun 4 – Jun 25 | 22–35 |
| Rhubarb | — | — | Jun 11 | — | 365–730 |
| Romanesco | Apr 16 | May 7 | May 21 | Aug 6 – Sep 17 | 75–100 |
| Rutabaga | — | May 7 | — | Jul 30 – Sep 3 | 80–100 |
| Salsify | — | May 7 | — | Aug 20 – Oct 1 | 100–130 |
| Savoy Cabbage | Apr 16 | May 7 | May 21 | Jul 30 – Sep 24 | 70–110 |
| Scallions | Apr 16 | May 7 | May 21 | Jul 16 – Aug 13 | 50–70 |
| Scarlet Runner Beans | Mar 26 | May 28 | Jun 4 | Aug 6 – Sep 10 | 60–80 |
| Shallot | Apr 16 | May 7 | May 21 | Aug 20 – Oct 8 | 90–120 |
| Shiso | Apr 2 | May 28 | Jun 4 | Jul 30 – Sep 24 | 50–70 |
| Snap Peas | Mar 26 | May 28 | Jun 4 | Jul 30 – Sep 24 | 55–70 |
| Snow Peas | Apr 16 | May 7 | May 21 | Jul 16 – Sep 10 | 50–65 |
| Soybeans | — | May 28 | — | Aug 20 – Oct 15 | 80–120 |
| Spaghetti Squash | Apr 16 | May 28 | Jun 4 | Sep 3 – Oct 1 | 85–100 |
| Spinach | Apr 16 | May 7 | May 21 | Jun 25 – Aug 27 | 35–50 |
| Squash (Summer) | Apr 16 | May 28 | Jun 4 | Jul 23 – Sep 24 | 45–65 |
| Squash (Winter) | Apr 16 | May 28 | Jun 4 | Aug 27 – Oct 22 | 80–120 |
| Sunchoke | — | — | Jun 4 | Sep 24 – Nov 19 | 110–150 |
| Sunflower | Mar 26 | May 28 | Jun 4 | Aug 13 – Oct 1 | 70–100 |
| Sweet Corn | — | May 28 | — | Jul 30 – Sep 10 | 60–90 |
| Sweet Potatoes | Mar 26 | May 28 | Jun 4 | Sep 3 – Oct 22 | 90–120 |
| Tatsoi | Apr 16 | May 7 | May 21 | Jun 25 – Jul 30 | 35–50 |
| Tomatillo | Mar 26 | May 28 | Jun 4 | Aug 6 – Oct 15 | 60–85 |
| Tomatoes | Mar 26 | May 28 | Jun 4 | Aug 6 – Oct 15 | 60–85 |
| Turnip | — | May 7 | — | Jun 18 – Jul 23 | 40–60 |
| Watercress | Apr 16 | May 7 | May 21 | Jul 2 – Aug 6 | 40–60 |
| Watermelon | Apr 16 | May 28 | Jun 4 | Aug 13 – Oct 1 | 70–100 |
| Wax Beans | — | May 28 | — | Jul 23 – Sep 17 | 50–65 |
| Winter Melon | Mar 26 | May 28 | Jun 4 | Sep 3 – Oct 22 | 90–120 |
| Yard Long Beans | Mar 26 | May 28 | Jun 4 | Jul 30 – Sep 10 | 55–80 |
| Zucchini | Apr 16 | May 28 | Jun 4 | Jul 23 – Sep 17 | 45–60 |
🍓 Fruits to Grow in Iron County
27 fruits that grow well in Zone 6b with planting dates for Iron County.
Show all 27 fruits with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Harvest | Days to Maturity |
|---|---|---|---|---|---|
| Alpine Strawberries | — | — | Jun 11 | Sep 10 – Dec 24 | 90–180 |
| Aronia | — | — | Jun 11 | — | 730–1095 |
| Blackberries | — | — | Jun 11 | — | 365–730 |
| Blueberries | — | — | Jun 11 | — | 730–1095 |
| Boysenberries | — | — | Jun 11 | — | 365–730 |
| Cantaloupe | — | — | Jun 11 | Aug 20 – Sep 24 | 70–90 |
| Che Fruit | — | — | Jun 11 | — | 1095–1825 |
| Cranberries | — | — | Jun 11 | — | 730–1095 |
| Currants | — | — | Jun 11 | — | 730–1095 |
| Elderberries | — | — | Jun 11 | — | 730–1095 |
| Goji Berries | — | — | Jun 11 | — | 730–1095 |
| Gooseberries | — | — | Jun 11 | — | 730–1095 |
| Grapes | — | — | Jun 11 | — | 730–1095 |
| Ground Cherry | — | — | Jun 11 | Aug 20 – Oct 15 | 65–80 |
| Hardy Kiwi | — | — | Jun 11 | — | 1095–1825 |
| Haskaps | — | — | Jun 11 | — | 730–1095 |
| Honeydew | — | — | Jun 11 | Sep 3 – Oct 15 | 80–110 |
| Jostaberry | — | — | Jun 11 | — | 730–1095 |
| Lingonberries | — | — | Jun 11 | — | 730–1095 |
| Medlar | — | — | Jun 11 | — | 1095–1825 |
| Mulberries | — | — | Jun 11 | — | 730–1825 |
| Pawpaw | — | — | Jun 11 | — | 1095–2555 |
| Persimmon | — | — | Jun 11 | — | 1095–2555 |
| Quince | — | — | Jun 11 | — | 1095–1825 |
| Raspberries | — | — | Jun 11 | — | 365–730 |
| Serviceberries | — | — | Jun 11 | — | 730–1095 |
| Strawberries | — | — | Jun 11 | Sep 10 – Dec 24 | 90–365 |
🌿 Herbs to Grow in Iron County
38 herbs that grow well in Zone 6b with planting dates for Iron County.
Show all 38 herbs with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Harvest | Days to Maturity |
|---|---|---|---|---|---|
| Angelica | Apr 16 | May 7 | May 14 | — | 365–730 |
| Anise | Apr 16 | May 7 | May 14 | Aug 13 – Oct 29 | 90–120 |
| Basil | Apr 2 | May 28 | Jun 4 | Jul 30 – Oct 1 | 50–75 |
| Bee Balm | — | — | May 28 | Aug 27 – Nov 12 | 90–120 |
| Borage | Apr 16 | May 7 | May 14 | Jul 9 – Aug 27 | 50–60 |
| Caraway | Apr 16 | May 7 | May 14 | — | 365–450 |
| Catnip | — | — | May 28 | Jul 30 – Oct 1 | 60–80 |
| Chamomile | Apr 16 | May 7 | May 14 | Jul 16 – Sep 24 | 60–90 |
| Chervil | Apr 16 | May 7 | May 14 | Jun 25 – Aug 27 | 40–60 |
| Chives | — | — | May 28 | Jul 30 – Oct 8 | 60–90 |
| Cilantro | Apr 16 | May 7 | May 14 | Jun 25 – Aug 27 | 40–60 |
| Comfrey | — | — | May 28 | Jul 30 – Oct 8 | 60–90 |
| Cumin | Apr 16 | May 7 | May 14 | Aug 27 – Oct 29 | 100–120 |
| Dill | Apr 16 | May 7 | May 14 | Jun 25 – Aug 27 | 40–60 |
| Echinacea | — | — | May 28 | Oct 1 – Dec 10 | 120–180 |
| Epazote | Apr 2 | May 28 | Jun 4 | Jul 23 – Sep 17 | 45–60 |
| Fennel (herb) | Apr 16 | May 7 | May 14 | Jul 16 – Sep 24 | 60–90 |
| Feverfew | — | — | May 28 | Aug 27 – Nov 12 | 90–120 |
| Garlic Chives | — | — | May 28 | Jul 30 – Oct 8 | 60–90 |
| Horehound | — | — | May 28 | Aug 13 – Oct 8 | 75–90 |
| Hyssop | — | — | May 28 | Aug 6 – Oct 8 | 70–90 |
| Lavender | — | — | May 28 | Aug 27 – Dec 10 | 90–200 |
| Lemon Balm | — | — | May 28 | Jul 30 – Sep 17 | 60–70 |
| Lemon Thyme | — | — | May 28 | Aug 6 – Oct 8 | 70–90 |
| Lovage | — | — | May 28 | Aug 6 – Oct 8 | 70–90 |
| Marjoram | — | — | May 28 | Jul 30 – Oct 8 | 60–90 |
| Mint | — | — | May 28 | Jul 30 – Oct 8 | 60–90 |
| Oregano | — | — | May 28 | Jul 30 – Oct 8 | 60–90 |
| Parsley | Apr 16 | May 7 | May 14 | Jul 16 – Sep 17 | 60–80 |
| Rue | — | — | May 28 | Aug 6 – Oct 8 | 70–90 |
| Sage | — | — | May 28 | Aug 13 – Oct 8 | 75–90 |
| Savory | — | — | May 28 | Jul 23 – Sep 17 | 50–70 |
| Sorrel | Apr 16 | May 7 | May 14 | Jun 25 – Aug 27 | 40–60 |
| Tarragon | — | — | May 28 | Jul 30 – Oct 8 | 60–90 |
| Thai Basil | Apr 2 | May 28 | Jun 4 | Jul 30 – Oct 1 | 50–75 |
| Thyme | — | — | May 28 | Aug 6 – Oct 8 | 70–90 |
| Valerian | — | — | May 28 | Oct 1 – Dec 10 | 120–180 |
| Yarrow | — | — | May 28 | Aug 27 – Nov 12 | 90–120 |
Monthly Planting Guide for Iron County
Gardening Guides & Resources
Helpful guides from The Ultimate Homestead to improve your garden in Iron County.
Frequently Asked Questions
What planting zone is Iron County, UT?
Iron County is in USDA Hardiness Zone 6b. 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 Iron County, UT?
Based on 31 years of NOAA weather station data, the median last spring frost in Iron County falls around May 21. In 8 out of 10 years, last frost lands between May 10 and June 9 — a 30-day window of variability. Use June 9 as your conservative safe-to-plant date for frost-sensitive crops.
When is the first fall frost in Iron County, UT?
The median first fall frost in Iron County arrives around October 1. In cold years it can arrive as early as September 17; in mild years as late as October 16. Harvest or protect frost-sensitive crops — tomatoes, peppers, basil, squash — before this date.
How long is the growing season in Iron County?
Iron County has a frost-free growing season of approximately 133 days. Focus on short-season varieties and start warm-season crops indoors 6–8 weeks before last frost.
What is the soil like in Iron County for gardening?
Iron County has predominantly Loam soil with a pH range of 6.4–7.8 and Well Drained drainage. Most vegetables and herbs grow well with standard composting and seasonal soil amendment.
What is grown commercially in Iron County?
Iron County has commercial agriculture that includes Cattle, Hay, Wheat, Barley. These crops reflect the local climate and soil conditions — what succeeds commercially often translates well to home gardens in the same area.
Is Iron County a good location for home gardening?
Iron County scores 44/100 (Moderate) on our Microclimate Index, which combines frost reliability, drought pressure, soil challenge, elevation risk, and long-term climate trend. Gardening here benefits from close attention to frost timing and season extension due to the challenging microclimate factors.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Iron County gardeners in Zone 6b 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.
