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San Juan County, UT — Planting Guide

San Juan County, Utah Zone 7a July

Top priorities for San Juan County, Utah gardeners in July

Your San Juan County, Utah garden is entering a new phase. Here's what's on the schedule for July and why each task matters now.

Avg. last frost May 2
Avg. first frost October 11
Soil temp (4") 61°F
Watering Critical
Pest pressure High
Daylight 14.4 hrs
  1. Get peppers, astilbe, and begonias seeds going inside

    A seed-starting mix and a sunny window (or a grow light) are all you need. Keep soil warm — around 70°F — for fast germination.

  2. Harvest basil, carrots, and cucumber as they ripen

    The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.

Before August arrives, get these ready
  • First harvests: basil, cucumber, and green beans
  • Fall sowing: carrots, kale, and lettuce

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San Juan County is in USDA Zone 7a. The average last spring frost is May 2 and the first fall frost is October 11, giving you a growing season of approximately 162 days.

At an elevation of 5,225 ft, San Juan County receives approximately 13.7 in of rainfall annually. Summer highs average 84°F with winter lows around 12°F. The predominant soil type is Loam.

Based on 31 years of NOAA climate station data, the last frost date here varies by 41 days year to year — ranging from April 15 in warm years to May 26 in cold years. San Juan County scores 46/100 (Moderate) on the Microclimate Index.

🌡️ Zone

7a (0°F to 5°F min)

❄️ Last Frost

May 2

🍂 First Frost

October 11

📅 Growing Season

162 days

⛰️ Elevation

5,225 ft

🌧️ Annual Rainfall

13.7 in

San Juan County, UT Moderate season
162 days
Last Spring Frost May 2
162 growing days
First Fall Frost October 11

Monthly Watering Calendar for San Juan County

When you'll need to water your garden — based on average monthly rainfall vs. the ~1 inch/week most gardens need.

Why it matters: Mulch reduces watering needs 30-50% by cutting evaporation. San Juan County's 14" annual rainfall might be enough for vegetables in some months and not in others — a 2-3" mulch layer evens the swing.

1"/wk 0" 1.3" 2.5" 3.8" 5" Jan 1" Feb 0.9" Mar 1.1" +3" Apr 1.3" +2.7" May 1.6" +3.3" Jun 1" +3.3" Jul 1" +2.7" Aug 1.6" +3.1" Sep 1.2" +3.1" Oct 1.2" Nov 0.9" Dec 0.9"
Rainfall sufficient Supplemental water needed Heavy watering required - - - 1"/week garden need
View detailed monthly data
MonthAvg RainfallRainy DaysExtra Water NeededWatering Effort
Jan 1 in 6 days None
Feb 0.9 in 5 days None
Mar 1.1 in 7 days None
Apr 1.3 in 8 days 3 in High
May 1.6 in 8 days 2.7 in High
Jun 1 in 4 days 3.3 in Critical
Jul 1 in 6 days 3.3 in Critical
Aug 1.6 in 7 days 2.7 in High
Sep 1.2 in 5 days 3.1 in Critical
Oct 1.2 in 5 days 3.1 in Critical
Nov 0.9 in 6 days None
Dec 0.9 in 7 days None

Annual total: 13.7 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.

San Juan County Soil Profile

Soil Type

Loam

Soil pH

6.5-7.8

Drainage

Well Drained

Frost Risk Probability

Based on 31 years of NOAA weather station data from 3 stations

Too early frost risk Safe to Plant May 2 → Oct 11 162 frost-free days Protect crops frost returns Apr May Jun Jul Aug Sep Oct Nov Safe: May 26 Protect by: Oct 28

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) May 26 Oct 28 155 days
Cautious May 11 Oct 16 158 days
Average year May 2 Oct 11 162 days
Optimistic Apr 20 Oct 4 167 days
Aggressive (risky) Apr 15 Sep 21 159 days
📊
How predictable are frost dates here?

Not very — frost dates can vary by ±41 days year-to-year. Use the "Conservative" row in the table below, and keep row covers handy for surprise late frosts.

Gardening Difficulty Score

46 Moderate
Frost Timing Risk
10.0/10
Drought Risk
5.5/10
Soil Difficulty
1.0/10
Altitude Challenge
8.5/10
Climate Shift
0.7/10
Rainfall Challenge
6.5/10

San Juan County presents some gardening challenges. Choose adapted varieties and plan around frost dates.

Zone 7a Frost Countdown
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Loading...
Last Frost: May 2 First Frost: Oct 11

Local Gardening Help in San Juan 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 San Juan County's climate and soil.

County Extension Office

San Juan 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.

Find Master Gardeners in UT →

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.

Request a Soil Test →

Services Available in San Juan County

Soil testing Arid gardening Pest identification
Finding local nurseries & garden centers in San Juan County

Why Buy Local

Local nurseries carry plants that are proven to grow in your area. Staff can give you advice specific to San Juan 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 San Juan County UT" or "garden center San Juan 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 San Juan County UT" or check your extension office and local parks department. Facebook groups like "San Juan 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
After Okra (harvest ends Sep 5) 36 days until frost
After Chard (harvest ends Aug 15) 57 days until frost
After Cabbage (harvest ends Aug 29) 43 days until frost
After Snap Peas (harvest ends Sep 5) 36 days until frost
After Green Beans (harvest ends Aug 22) 50 days until frost
After Zucchini (harvest ends Aug 29) 43 days until frost

Sunlight & Day Length in San Juan County

Monthly daylight hours and peak sun — critical for onion varieties, photoperiod-sensitive plants, and solar garden planning.

Why it matters: Photoperiod-sensitive crops will fail spectacularly if planted at the wrong latitude. Sweet onions in Michigan? Tiny. Spanish onions in Florida? Tiny. Match variety to San Juan County's daylight pattern and you'll see the difference.

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.

14hr 12hr 4h 7h 10h 13h 16h Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Daylight hours (sunrise to sunset) Peak sun hours (direct sunlight after cloud cover) ▪ Gold zone = long day (14+ hr) ▪ Blue zone = short day (<12 hr)

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
MonthDaylight HoursPeak Sun HoursDay Length
January 9.7 hr 5.3 hr Short day
February 10.6 hr 6 hr Short day
March 11.7 hr 7.3 hr Short day
April 13 hr 7.5 hr Neutral
May 14 hr 8.4 hr Long day
June 14.6 hr 10.1 hr Long day
July 14.4 hr 9.8 hr Long day
August 13.5 hr 9.2 hr Neutral
September 12.2 hr 8.4 hr Neutral
October 11 hr 7.2 hr Short day
November 9.9 hr 5.7 hr Short day
December 9.4 hr 5 hr Short day

Peak sun hours factor in typical cloud cover — use these for solar panel and shade-planning calculations.

Soil Temperature & Composting in San Juan County

Monthly soil temps tell you when to plant warm-season crops, and when your compost pile is actively working.

The practical takeaway: Soil heats slower than air in spring and cools slower in fall. That's why "warm" April air doesn't mean "plant tomatoes" — soil still trails by weeks. San Juan County's monthly soil curve makes the lag visible.

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.

60°F 70°F 20° 40° 60° 80° Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
4" depth 8" depth - - - 60°F (corn, beans) - - - 70°F (tomatoes, peppers)
View detailed monthly data
MonthSoil 4" DeepSoil 8" DeepCompost ActivityTime to Finish
Jan 9°F 16°F ❄️ Dormant ~36 weeks
Feb 11°F 16°F ❄️ Dormant ~36 weeks
Mar 16°F 20°F ❄️ Dormant ~36 weeks
Apr 30°F 30°F ❄️ Dormant ~36 weeks
May 44°F 41°F 🐢 Slow ~24 weeks
Jun 55°F 49°F ♻️ Active ~14 weeks
Jul 61°F 57°F ♻️ Active ~14 weeks
Aug 65°F 60°F 🔥 Peak ~8 weeks
Sep 58°F 55°F ♻️ Active ~14 weeks
Oct 43°F 46°F 🐢 Slow ~24 weeks
Nov 28°F 36°F ❄️ Dormant ~36 weeks
Dec 17°F 24°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 San Juan County

Computed from local climate patterns — warmer, humid conditions increase pest generations and fungal disease risk.

The practical takeaway: Warm humid regions cycle through pest generations 3-5x faster than cold dry regions. San Juan County's pest score is your early-warning system: high score means commit to disease-resistant varieties and accept some crop loss to bugs.

Insect Pest Pressure

5.3 / 10

Moderate — common pests appear but manageable with monitoring.

Disease Risk

1 / 10

Low disease risk — dry conditions reduce fungal problems.

Seasonal Risk

Spring Low
Summer High
Fall Low
Winter Low
View 6 common pests in your area
PestRisk LevelPeak Months
Aphids Moderate May, Jun, Jul, Aug
Japanese beetles Moderate Jun, Jul, Aug
Squash bugs Low Jun, Jul, Aug
Tomato hornworms Low Jul, Aug
Cabbage loopers Low May, Jun, Jul, Aug
Slugs Low Apr, May, Jun
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 San Juan County

Cover crops protect bare soil, fix nitrogen, suppress weeds, and improve soil structure — with planting dates calibrated for your area.

What this means for you: Cover crops protect microbial life through winter and summer. Bare soil bakes; covered soil stays cooler, moister, and biologically active. The difference shows up in next year's crops.

Spring Cover Crops (3 options) — Build soil before the main growing season
Crop Plant By Terminate N-Fixing Soil Benefit
Buckwheat May 11 Aug 16 Rapid growth, attracts pollinators, suppresses weeds
Sorghum-sudan grass May 14 Aug 2 Massive biomass, breaks compaction, suppresses nematodes
White clover Apr 3 Aug 2 ✓ 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 May 17 Sep 20 Deep roots break compaction, attract pollinators and beneficial insects
Fall Cover Crops (6 options) — Plant after harvest to protect soil over winter
Crop Plant By Terminate N-Fixing Soil Benefit
Austrian winter peas Aug 16 Apr 18 ✓ Yes Fixes nitrogen, good for heavy clay soils
Daikon radish Aug 17 Apr 11 Deep taproot breaks compaction, excellent for clay soils
Hairy vetch Aug 5 Apr 11 ✓ Yes Excellent nitrogen fixer, good for depleted soils
Oats Aug 29 Apr 11 Quick biomass, winterkills in cold zones — no spring tillage needed
Winter rye Jul 12 Apr 18 Suppresses weeds, prevents erosion, breaks up compacted soil
Winter wheat Jul 21 Apr 18 Erosion control, weed suppression, good biomass

Wind & Microclimate in San Juan County

Quick context: Pollinators avoid windy days. San Juan County's 10.4 mph average wind isn't enough to stop bees and butterflies — but plant fruiting crops (tomatoes, peppers, squash) in protected microclimates and you'll see noticeably better fruit set.

Wind dries soil, stresses plants, and affects frost patterns. Understanding your exposure helps with garden placement.

Seasonal Wind Speed

Spring: 15 mph   Summer: 10 mph

Fall: 13 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

High

Hilly terrain with 1,084 ft of elevation range — cold air pools in low spots. Avoid planting frost-sensitive crops in valleys.

Rainwater Harvesting in San Juan County

How much water you can collect, when to collect it, and what size system you need for your garden.

For new gardeners: Rainwater is unchlorinated, unfluoridated, and at ambient temperature — plants actually prefer it. San Juan County's 14" annual rainfall means even a small 50-gallon barrel catches enough for a few weeks of garden watering between storms.

Annual Collection

6,828 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 2,000 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, Aug, Sep

Highest rainfall months — your barrels will fill up quickly during these months.

Months to Draw From Storage

Feb, Nov, 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 13.7 inches of rain per year
  • A 1,000 sq ft roof can collect roughly 6,828 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 San Juan County

Soil Type

Loam

Soil pH 6.5–7.8 · Well Drained drainage

Good candidate for raised beds to maximise drainage and extend the season.

Watering Needs

Drought stress: 5.5/10

Moderate drought pressure. Drip irrigation and mulching are highly recommended to maintain soil moisture through summer.

Season Tips

162-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.

Your Free Printable Garden Planner

Plan every bed, every planting, every harvest — in one place. This 22-page printable includes your zone's planting calendar, a month-by-month task list, a seed inventory tracker, a harvest log, and succession-planting charts. Built to print, write in, and actually use all season.

Instant PDF download. No spam, unsubscribe any time.

Recommended for Your Garden

🧪
Soil Test Kit $12-25

Test your soil pH, nitrogen, phosphorus, and potassium levels before planting.

📏
Digital pH Meter $10-20

Get instant, accurate soil pH readings to fine-tune your amendments.

🍂
Organic Compost $8-30

Boost soil fertility and structure with rich, well-aged organic compost.

🥬 Vegetables to Grow in San Juan County

112 vegetables that grow well in Zone 7a with planting dates for San Juan County.

Show all 112 vegetables with planting dates
Plant Start Indoors Direct Sow Transplant Fall Plant Harvest Days to Maturity
Acorn Squash Apr 4 May 9 May 16 Aug 8 – Sep 12 80–100
Amaranth Mar 14 May 9 May 16 Aug 15 – Oct 3 90–120
Artichoke May 16 Sep 19 – Nov 28 120–180
Arugula Mar 28 Apr 18 May 2 Aug 2 Jun 6 – Aug 8 30–50
Asparagus May 16 730–1095
Beets Apr 18 Aug 2 Jun 13 – Jul 11 50–70
Belgian Endive Mar 28 Apr 18 May 2 Aug 2 Aug 22 – Oct 17 110–150
Bitter Melon Mar 14 May 9 May 16 Jul 18 – Aug 29 60–90
Black Beans May 9 Aug 8 – Sep 26 90–120
Bok Choy Mar 28 Apr 18 May 2 Aug 2 Jun 13 – Jul 18 40–60
Broccoli Mar 28 Apr 18 May 2 Aug 2 Jul 4 – Aug 15 60–90
Broccoli Rabe Mar 28 Apr 18 May 2 Aug 2 Jun 13 – Jul 18 40–60
Brussels Sprouts Mar 28 Apr 18 May 2 Aug 2 Aug 1 – Sep 26 90–130
Butternut Squash Apr 4 May 9 May 16 Aug 15 – Sep 19 85–110
Cabbage Mar 28 Apr 18 May 2 Aug 2 Jul 4 – Aug 29 60–100
Calabash Mar 14 May 9 May 16 Aug 8 – Oct 3 80–120
Cardoon May 16 Sep 19 – Oct 31 120–150
Carrots Apr 18 Aug 2 Jun 20 – Jul 25 60–80
Cauliflower Mar 28 Apr 18 May 2 Aug 2 Jun 27 – Aug 29 55–100
Celeriac Mar 28 Apr 18 May 2 Aug 2 Aug 15 – Sep 19 100–120
Celery Mar 28 Apr 18 May 2 Aug 2 Jul 25 – Sep 19 80–120
Celtuce Mar 28 Apr 18 May 2 Aug 2 Jul 4 – Aug 15 60–90
Chard Mar 28 Apr 18 May 2 Aug 2 Jun 27 – Aug 15 50–60
Chayote Mar 14 May 9 May 16 Sep 19 – Nov 28 120–180
Chickpeas Mar 28 Apr 18 May 2 Aug 2 Jul 25 – Sep 5 80–110
Chicory Mar 28 Apr 18 May 2 Aug 2 Jul 4 – Aug 15 60–85
Chinese Cabbage Mar 28 Apr 18 May 2 Aug 2 Jun 27 – Jul 25 50–70
Christmas Lima Beans Mar 14 May 9 May 16 Aug 8 – Sep 12 80–100
Collard Greens Mar 28 Apr 18 May 2 Aug 2 Jun 27 – Aug 29 55–75
Corn May 9 Jul 11 – Sep 5 60–100
Cowpeas May 9 Jul 11 – Aug 22 60–90
Cress Mar 28 Apr 18 May 2 Aug 2 May 16 – Jun 6 14–21
Crookneck Squash Apr 4 May 9 May 16 Jul 4 – Aug 1 45–60
Crosne Apr 18 Aug 2 Sep 19 – Nov 21 150–200
Cucumber Apr 4 May 9 May 16 Jul 11 – Sep 5 50–70
Daikon Apr 18 Aug 2 Jun 13 – Jul 11 50–70
Delicata Squash Apr 4 May 9 May 16 Aug 8 – Sep 12 80–100
Edamame May 9 Jul 25 – Sep 5 75–100
Eggplant Feb 28 May 9 May 16 Jul 25 – Sep 26 65–85
Endive Mar 28 Apr 18 May 2 Aug 2 Jun 20 – Jul 25 45–65
Escarole Mar 28 Apr 18 May 2 Aug 2 Jun 27 – Jul 25 50–70
Fava Beans Mar 28 Apr 18 May 2 Aug 2 Jul 18 – Aug 29 75–100
Fennel Mar 14 May 9 May 16 Jul 18 – Aug 29 60–90
Garlic Aug 30 Nov 29 – Apr 11 90–240
Green Beans May 9 Jul 4 – Aug 29 50–65
Horseradish May 16 Sep 19 – Nov 28 120–180
Hot Peppers Feb 28 May 9 May 16 Jul 25 – Oct 31 70–120
Hubbard Squash Apr 4 May 9 May 16 Aug 29 – Oct 3 100–120
Jicama Mar 14 May 9 May 16 Sep 19 – Nov 28 120–180
Kabocha Apr 4 May 9 May 16 Aug 15 – Sep 12 85–100
Kai Lan Mar 28 Apr 18 May 2 Aug 2 Jun 20 – Jul 18 45–60
Kale Mar 28 Apr 18 May 2 Aug 2 Jun 27 – Aug 22 50–70
Kidney Beans May 9 Aug 8 – Sep 12 85–110
Kohlrabi Mar 28 Apr 18 May 2 Aug 2 Jun 20 – Jul 25 45–65
Komatsuna Mar 28 Apr 18 May 2 Aug 2 Jun 6 – Jul 11 35–50
Leeks Mar 28 Apr 18 May 2 Aug 2 Aug 1 – Oct 17 90–150
Lentils Mar 28 Apr 18 May 2 Aug 2 Jul 25 – Sep 5 80–110
Lettuce Mar 28 Apr 18 May 2 Aug 2 Jun 6 – Aug 15 30–60
Lima Beans May 9 Jul 11 – Aug 22 60–90
Loofah Mar 14 May 9 May 16 Aug 29 – Oct 31 100–150
Luffa Mar 14 May 9 May 16 Aug 15 – Oct 31 90–150
Mache Mar 28 Apr 18 May 2 Aug 2 Jun 13 – Jul 18 40–60
Malabar Spinach Mar 14 May 9 May 16 Jul 11 – Aug 8 55–70
Melon Apr 4 May 9 May 16 Jul 25 – Sep 12 70–100
Microgreens Mar 28 Apr 18 May 2 Aug 2 May 9 – Jun 6 7–21
Mitsuba Mar 28 Apr 18 Apr 25 Aug 2 Jun 20 – Aug 15 50–70
Mizuna Mar 28 Apr 18 May 2 Aug 2 Jun 6 – Jul 4 30–45
Mustard Greens Mar 28 Apr 18 May 2 Aug 2 Jun 6 – Aug 8 30–50
Napa Cabbage Mar 28 Apr 18 May 2 Aug 2 Jun 27 – Aug 1 55–75
New Zealand Spinach Mar 14 May 9 May 16 Jul 11 – Aug 8 55–70
Okra Mar 14 May 9 May 16 Jul 11 – Sep 5 50–65
Onion Mar 28 Apr 18 May 2 Aug 2 Aug 1 – Sep 19 90–120
Pac Choi Mar 28 Apr 18 May 2 Aug 2 Jun 13 – Jul 11 40–55
Parsnip Apr 18 Aug 2 Aug 1 – Sep 12 100–130
Patty Pan Squash Apr 4 May 9 May 16 Jul 4 – Aug 1 45–60
Peas Mar 28 Apr 18 May 2 Aug 2 Jun 27 – Aug 22 55–70
Peppers Feb 28 May 9 May 16 Jul 18 – Sep 26 60–90
Pole Beans Mar 14 May 9 May 16 Jul 11 – Sep 5 55–70
Potatoes Mar 14 May 9 May 16 Jul 25 – Oct 3 70–120
Pumpkin Apr 4 May 9 May 16 Aug 15 – Oct 3 85–120
Purslane Mar 28 Apr 18 May 2 Aug 2 Jun 13 – Jul 18 40–60
Radicchio Mar 28 Apr 18 May 2 Aug 2 Jul 4 – Aug 8 60–80
Radish Apr 18 Aug 2 May 16 – Jun 6 22–35
Rhubarb May 23 365–730
Romanesco Mar 28 Apr 18 May 2 Aug 2 Jul 18 – Aug 29 75–100
Rutabaga Apr 18 Aug 2 Jul 11 – Aug 15 80–100
Salsify Apr 18 Aug 2 Aug 1 – Sep 12 100–130
Savoy Cabbage Mar 28 Apr 18 May 2 Aug 2 Jul 11 – Sep 5 70–110
Scallions Mar 28 Apr 18 May 2 Aug 2 Jun 27 – Jul 25 50–70
Scarlet Runner Beans Mar 14 May 9 May 16 Jul 18 – Aug 22 60–80
Shallot Mar 28 Apr 18 May 2 Aug 2 Aug 1 – Sep 19 90–120
Shiso Mar 14 May 9 May 16 Jul 11 – Sep 5 50–70
Snap Peas Mar 14 May 9 May 16 Jul 11 – Sep 5 55–70
Snow Peas Mar 28 Apr 18 May 2 Aug 2 Jun 27 – Aug 22 50–65
Soybeans May 9 Aug 1 – Sep 26 80–120
Spaghetti Squash Apr 4 May 9 May 16 Aug 15 – Sep 12 85–100
Spinach Mar 28 Apr 18 May 2 Aug 2 Jun 6 – Aug 8 35–50
Squash (Summer) Apr 4 May 9 May 16 Jul 4 – Sep 5 45–65
Squash (Winter) Apr 4 May 9 May 16 Aug 8 – Oct 3 80–120
Sunchoke May 16 Sep 5 – Oct 31 110–150
Sweet Corn May 9 Jul 11 – Aug 22 60–90
Sweet Potatoes Mar 14 May 9 May 16 Aug 15 – Oct 3 90–120
Tatsoi Mar 28 Apr 18 May 2 Aug 2 Jun 6 – Jul 11 35–50
Tomatillo Mar 14 May 9 May 16 Jul 18 – Sep 26 60–85
Tomatoes Mar 14 May 9 May 16 Jul 18 – Sep 26 60–85
Turnip Apr 18 Aug 2 May 30 – Jul 4 40–60
Watercress Mar 28 Apr 18 May 2 Aug 2 Jun 13 – Jul 18 40–60
Watermelon Apr 4 May 9 May 16 Jul 25 – Sep 12 70–100
Wax Beans May 9 Jul 4 – Aug 29 50–65
Winter Melon Mar 14 May 9 May 16 Aug 15 – Oct 3 90–120
Yard Long Beans Mar 14 May 9 May 16 Jul 11 – Aug 22 55–80
Zucchini Apr 4 May 9 May 16 Jul 4 – Aug 29 45–60

🍓 Fruits to Grow in San Juan County

31 fruits that grow well in Zone 7a with planting dates for San Juan County.

Show all 31 fruits with planting dates
Plant Start Indoors Direct Sow Transplant Fall Plant Harvest Days to Maturity
Alpine Strawberries May 23 Aug 22 – Dec 5 90–180
Aronia May 23 730–1095
Blackberries May 23 365–730
Blueberries May 23 730–1095
Boysenberries May 23 365–730
Cantaloupe May 23 Aug 1 – Sep 5 70–90
Che Fruit May 23 1095–1825
Cranberries May 23 730–1095
Currants May 23 730–1095
Elderberries May 23 730–1095
Figs May 23 730–1825
Goji Berries May 23 730–1095
Gooseberries May 23 730–1095
Grapes May 23 730–1095
Ground Cherry May 23 Aug 1 – Sep 26 65–80
Hardy Kiwi May 23 1095–1825
Haskaps May 23 730–1095
Honeydew May 23 Aug 15 – Sep 26 80–110
Jostaberry May 23 730–1095
Kiwi May 23 1095–1825
Lingonberries May 23 730–1095
Loquat May 23 730–1825
Medlar May 23 1095–1825
Mulberries May 23 730–1825
Pawpaw May 23 1095–2555
Persimmon May 23 1095–2555
Pomegranate May 23 730–1095
Quince May 23 1095–1825
Raspberries May 23 365–730
Serviceberries May 23 730–1095
Strawberries May 23 Aug 22 – Jan 2 90–365

🌿 Herbs to Grow in San Juan County

36 herbs that grow well in Zone 7a with planting dates for San Juan County.

Show all 36 herbs with planting dates
Plant Start Indoors Direct Sow Transplant Fall Plant Harvest Days to Maturity
Angelica Mar 28 Apr 18 Apr 25 Aug 2 365–730
Anise Mar 28 Apr 18 Apr 25 Aug 2 Jul 25 – Oct 10 90–120
Basil Mar 14 May 9 May 16 Jul 11 – Sep 12 50–75
Bee Balm May 9 Aug 8 – Oct 24 90–120
Borage Mar 28 Apr 18 Apr 25 Aug 2 Jun 20 – Aug 8 50–60
Caraway Mar 28 Apr 18 Apr 25 Aug 2 365–450
Catnip May 9 Jul 11 – Sep 12 60–80
Chamomile Mar 28 Apr 18 Apr 25 Aug 2 Jun 27 – Sep 5 60–90
Chervil Mar 28 Apr 18 Apr 25 Aug 2 Jun 6 – Aug 8 40–60
Chives May 9 Jul 11 – Sep 19 60–90
Cilantro Mar 28 Apr 18 Apr 25 Aug 2 Jun 6 – Aug 8 40–60
Comfrey May 9 Jul 11 – Sep 19 60–90
Cumin Mar 28 Apr 18 Apr 25 Aug 2 Aug 8 – Oct 10 100–120
Dill Mar 28 Apr 18 Apr 25 Aug 2 Jun 6 – Aug 8 40–60
Epazote Mar 14 May 9 May 16 Jul 4 – Aug 29 45–60
Fennel (herb) Mar 28 Apr 18 Apr 25 Aug 2 Jun 27 – Sep 5 60–90
Feverfew May 9 Aug 8 – Oct 24 90–120
Garlic Chives May 9 Jul 11 – Sep 19 60–90
Horehound May 9 Jul 25 – Sep 19 75–90
Hyssop May 9 Jul 18 – Sep 19 70–90
Lemon Balm May 9 Jul 11 – Aug 29 60–70
Lemon Thyme May 9 Jul 18 – Sep 19 70–90
Lovage May 9 Jul 18 – Sep 19 70–90
Marjoram May 9 Jul 11 – Sep 19 60–90
Mint May 9 Jul 11 – Sep 19 60–90
Oregano May 9 Jul 11 – Sep 19 60–90
Parsley Mar 28 Apr 18 Apr 25 Aug 2 Jun 27 – Aug 29 60–80
Rosemary May 9 Aug 1 – Dec 19 80–180
Rue May 9 Jul 18 – Sep 19 70–90
Sage May 9 Jul 25 – Sep 19 75–90
Savory May 9 Jul 4 – Aug 29 50–70
Sorrel Mar 28 Apr 18 Apr 25 Aug 2 Jun 6 – Aug 8 40–60
Tarragon May 9 Jul 11 – Sep 19 60–90
Thai Basil Mar 14 May 9 May 16 Jul 11 – Sep 12 50–75
Thyme May 9 Jul 18 – Sep 19 70–90
Valerian May 9 Sep 12 – Dec 19 120–180

🌸 Flowers to Grow in San Juan County

53 flowers that grow well in Zone 7a with planting dates for San Juan County.

Show all 53 flowers with planting dates
Plant Start Indoors Direct Sow Transplant Fall Plant Bloom Days to Maturity
Ageratum Mar 21 May 2 May 2 Jun 27 – Oct 17 60–75
Alliums Sep 6 Oct 4 – Oct 25 28–42
Anemones Aug 16 Aug 30 – Sep 27 90–120
Astilbe Feb 28 May 9 Jul 18 – Sep 12 70–100
Bachelor's Button Mar 21 Mar 28 May 2 Aug 16 Jul 4 – Oct 3 60–90
Begonias Feb 21 May 2 Jul 11 – Oct 31 70–90
Black-eyed Susan Feb 28 May 2 May 9 Jul 18 – Nov 21 60–80
Bleeding Hearts Feb 28 May 9 Jun 27 – Aug 1 60–90
Calendula Mar 21 Mar 28 May 2 Aug 16 Jun 20 – Oct 3 50–70
California Poppy Apr 4 Aug 16 Jun 13 – Aug 22 60–90
Celosia Apr 4 May 2 May 2 Jul 4 – Oct 31 60–90
Columbine Mar 7 May 9 May 9 Jun 27 – Aug 1 70–100
Coreopsis Feb 28 May 2 May 9 Jul 11 – Nov 21 60–80
Cosmos Apr 4 May 2 May 2 Jul 11 – Oct 31 60–90
Crocus Sep 6 Aug 2 – Aug 23 10–20
Daffodils Sep 6 Aug 9 – Aug 30 20–40
Dahlias Apr 4 May 9 May 9 Jul 18 – Nov 21 70–120
Daylily Feb 28 May 9 Jul 18 – Nov 21 60–90
Dianthus Mar 7 Mar 28 Apr 11 May 30 – Aug 29 60–80
Echinacea (Purple Coneflower) Feb 28 May 9 May 9 Jul 25 – Nov 21 70–90
Foxglove Mar 7 May 9 May 9 Jun 27 – Aug 1 80–120
Gaillardia (Blanket Flower) Mar 14 May 9 May 9 Jul 18 – Dec 5 70–100
Geraniums Feb 21 May 2 Jul 11 – Oct 31 70–100
Gladiolus May 2 May 2 Jul 11 – Nov 14 70–100
Hostas Feb 21 May 9 Jul 18 – Nov 21 60–90
Hyacinths Sep 6 Aug 30 – Sep 20 14–28
Hydrangeas Feb 21 May 9 Jul 18 – Nov 7 90–150
Impatiens Mar 7 May 9 Jul 18 – Nov 7 60–75
Irises Division May 9 Jun 27 – Aug 1 60–100
Larkspur Apr 4 Aug 2 Jun 13 – Aug 22 60–90
Lavender Feb 28 May 16 Jul 25 – Oct 3 90–120
Lilies Division May 9 Jul 18 – Nov 7 70–120
Lobelia Feb 28 Apr 11 Jun 6 – Aug 29 70–80
Lupine Mar 7 May 9 May 9 Jun 27 – Aug 1 75–100
Marigolds Mar 21 May 2 May 2 Jun 27 – Oct 3 50–70
Nasturtium Apr 4 May 2 May 2 Jun 27 – Oct 31 55–65
Pansy Feb 21 May 2 Aug 2 Jun 27 – Sep 5 70–90
Peonies Division May 9 Jul 4 – Aug 8 90–120
Petunia Mar 7 May 9 Jul 18 – Nov 7 70–90
Phlox Feb 28 May 9 May 9 Jul 18 – Oct 10 80–110
Portulaca Apr 4 May 2 May 2 Jun 20 – Oct 17 50–70
Ranunculus Aug 16 Sep 13 – Oct 11 90–120
Roses Feb 21 May 9 Jul 18 – Nov 21 90–180
Salvia Mar 7 May 2 Jul 11 – Oct 31 70–90
Sedum (Stonecrop) Feb 28 May 9 Aug 29 – Nov 21 60–90
Snapdragon Feb 21 Apr 4 May 2 Aug 16 Jul 11 – Oct 3 70–100
Sunflower Apr 11 May 2 May 2 Jul 25 – Oct 31 70–100
Sweet Alyssum Mar 21 Apr 4 May 2 Aug 30 Jun 13 – Sep 5 45–60
Sweet Pea Mar 28 Aug 16 Jun 6 – Aug 29 65–85
Tulips Sep 6 Aug 23 – Sep 13 15–30
Vinca (Annual) Feb 21 May 2 Jul 11 – Oct 31 70–90
Yarrow Feb 28 May 2 May 9 Jul 11 – Nov 21 60–90
Zinnia Apr 4 May 2 May 2 Jul 11 – Oct 31 60–70

Monthly Planting Guide for San Juan County

Gardening Guides & Resources

Helpful guides from The Ultimate Homestead to improve your garden in San Juan County.

Frequently Asked Questions

What planting zone is San Juan County, UT?

San Juan County is in USDA Hardiness Zone 7a. 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 San Juan County, UT?

Based on 31 years of NOAA weather station data, the median last spring frost in San Juan County falls around May 2. In 8 out of 10 years, last frost lands between April 15 and May 26 — a 41-day window of variability. Use May 26 as your conservative safe-to-plant date for frost-sensitive crops.

When is the first fall frost in San Juan County, UT?

The median first fall frost in San Juan County arrives around October 11. In cold years it can arrive as early as September 21; in mild years as late as October 28. Harvest or protect frost-sensitive crops — tomatoes, peppers, basil, squash — before this date.

How long is the growing season in San Juan County?

San Juan County has a frost-free growing season of approximately 162 days. This is enough time for most warm-season crops including tomatoes, peppers, and squash with proper timing.

What is the soil like in San Juan County for gardening?

San Juan County has predominantly Loam soil with a pH range of 6.5–7.8 and Well Drained drainage. Most vegetables and herbs grow well with standard composting and seasonal soil amendment.

What is grown commercially in San Juan County?

San Juan County has commercial agriculture that includes Hay, Cattle, Wheat, Sugar Beets. These crops reflect the local climate and soil conditions — what succeeds commercially often translates well to home gardens in the same area.

Is San Juan County a good location for home gardening?

San Juan County scores 46/100 (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.

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A 22-page printable planner built for San Juan County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA GHCN-D daily station data (1994–2024) from 3 weather stations in or near San Juan County (31 years of records). Frost dates represent 50% probability averages; local conditions vary by elevation and microclimate. Last updated: July 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.