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Fallon County, MT — Planting Guide

Fallon County, Montana Zone 4b July

July to-do list for Fallon County, Montana

Your Fallon County, Montana 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 20
Avg. first frost September 20
Soil temp (4") 51°F
Watering High
Pest pressure High
Daylight 15.3 hrs
  1. Start basil, cucumber, and kale under lights

    Give them 6–8 weeks indoors before the last frost and you'll transplant into warm soil with seedlings that are already leaping.

  2. It's harvest week for carrots, green beans, and kale

    This is the payoff month. Bring a basket, bring a friend, and get into the beds.

August will be here before you know it — start on
  • Starting indoors: peppers, begonias, and geraniums
  • First harvests: basil, carrots, and cucumber
  • Fall sowing: alliums, crocus, and daffodils

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Fallon County is in USDA Zone 4b. The average last spring frost is May 20 and the first fall frost is September 20, giving you a growing season of approximately 123 days.

At an elevation of 6,441 ft, Fallon County receives approximately 19.8 in of rainfall annually. Summer highs average 81°F with winter lows around 4°F. The predominant soil type is Loam.

Based on 31 years of NOAA climate station data, the last frost date here varies by 29 days year to year — ranging from May 10 in warm years to June 8 in cold years. Fallon County scores 46/100 (Moderate) on the Microclimate Index.

🌡️ Zone

4b (-25°F to -20°F min)

❄️ Last Frost

May 20

🍂 First Frost

September 20

📅 Growing Season

123 days

⛰️ Elevation

6,441 ft

🌧️ Annual Rainfall

19.8 in

Fallon County, MT Short season
123 days
Last Spring Frost May 20
123 growing days
First Fall Frost September 20

Monthly Watering Calendar for Fallon County

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

What this means for you: Most vegetables want about 1 inch of water per week. Fallon County gets 20" a year — months that hit that 1"/week need zero supplemental watering; months that fall short, the table tells you how much to add. Saves you from drowning roots and from drought-stressing plants into bolting.

1"/wk 0" 1.3" 2.5" 3.8" 5" Jan 1.3" Feb 1.3" Mar 1.8" +2.2" Apr 2.1" +1.6" May 2.7" +2.9" Jun 1.4" +2.7" Jul 1.6" +2.4" Aug 1.9" +2.7" Sep 1.6" +2.6" Oct 1.7" Nov 1.2" Dec 1.2"
Rainfall sufficient Supplemental water needed Heavy watering required - - - 1"/week garden need
View detailed monthly data
MonthAvg RainfallRainy DaysExtra Water NeededWatering Effort
Jan 1.3 in 7 days None
Feb 1.3 in 5 days None
Mar 1.8 in 9 days None
Apr 2.1 in 8 days 2.2 in High
May 2.7 in 7 days 1.6 in High
Jun 1.4 in 5 days 2.9 in High
Jul 1.6 in 5 days 2.7 in High
Aug 1.9 in 6 days 2.4 in High
Sep 1.6 in 6 days 2.7 in High
Oct 1.7 in 5 days 2.6 in High
Nov 1.2 in 5 days None
Dec 1.2 in 7 days None

Annual total: 19.8 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.

Fallon County Soil Profile

Soil Type

Loam

Soil pH

6.2-8.3

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 20 → Sep 20 123 frost-free days Protect crops frost returns May Jun Jul Aug Sep Oct Nov Safe: Jun 8 Protect by: Oct 4

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 8 Oct 4 118 days
Cautious May 28 Sep 22 117 days
Average year May 20 Sep 20 123 days
Optimistic May 14 Sep 13 122 days
Aggressive (risky) May 10 Sep 5 118 days
📊
How predictable are frost dates here?

Not very — frost dates can vary by ±29 days year-to-year. Use the "Conservative" row in the table below, and keep row covers handy for surprise late frosts.

🌱
Is the growing season changing?

Slightly — seasons are trending a bit longer (0.5 days/decade). Historical frost dates are still reliable for planning.

Gardening Difficulty Score

46 Moderate
Frost Timing Risk
10.0/10
Drought Risk
5.5/10
Soil Difficulty
1.0/10
Altitude Challenge
10.0/10
Climate Shift
2.0/10
Rainfall Challenge
4.1/10

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

Zone 4b Frost Countdown
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Last Frost: May 20 First Frost: Sep 20

Local Gardening Help in Fallon 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 Fallon County's climate and soil.

County Extension Office

Fallon County Montana State University Extension Extension Office

Phone: 406-994-3402

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 MT →

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 Fallon County

Soil testing Short-season gardening Pest identification
Finding local nurseries & garden centers in Fallon County

Why Buy Local

Local nurseries carry plants that are proven to grow in your area. Staff can give you advice specific to Fallon 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 Fallon County MT" or "garden center Fallon 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 Fallon County MT" or check your extension office and local parks department. Facebook groups like "Fallon County Gardeners" or "Montana 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 1 more succession options
After Turnip (harvest ends Aug 5) 46 days until frost

Sunlight & Day Length in Fallon County

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

Why this matters: Onion varieties are sold by "short-day," "intermediate-day," and "long-day." Fallon County's latitude determines which to buy — and getting it wrong is the difference between baseball-sized bulbs and marbles.

Longest Day

15.6 hours

Summer solstice daylight

Shortest Day

8.4 hours

Winter solstice daylight

Peak Sun Hours

11.8 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 3h 7h 10h 14h 17h 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 8.8 hr 4.6 hr Short day
February 10.1 hr 6.1 hr Short day
March 11.6 hr 7.2 hr Short day
April 13.3 hr 7.4 hr Neutral
May 14.8 hr 9.1 hr Long day
June 15.6 hr 11.8 hr Long day
July 15.3 hr 10.6 hr Long day
August 14 hr 9.7 hr Long day
September 12.3 hr 8.9 hr Neutral
October 10.6 hr 6.8 hr Short day
November 9.2 hr 5.3 hr Short day
December 8.4 hr 4.7 hr Short day

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

Soil Temperature & Composting in Fallon County

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

Why this matters: Air temperature lies. Your air can be 70°F in April but the soil 4 inches down is still 50°F — too cold for tomatoes or peppers to root properly. Fallon County's soil temperature curve tells you the real planting window. A $5 soil thermometer pays for itself in one season.

Plant Warm Crops When

Soil reaches 60°F+

Soil rarely reaches 60°F — use black plastic mulch to warm soil.

Best Month to Compost

Jul

Microbial activity peaks when soil is warm.

Active Composting

2 months

Short season — insulate pile or use indoor vermicomposting.

60°F 18° 35° 53° 70° 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 -7°F 5°F ❄️ Dormant ~36 weeks
Feb -1°F 2°F ❄️ Dormant ~36 weeks
Mar 7°F 11°F ❄️ Dormant ~36 weeks
Apr 21°F 21°F ❄️ Dormant ~36 weeks
May 37°F 31°F ❄️ Dormant ~36 weeks
Jun 45°F 41°F 🐢 Slow ~24 weeks
Jul 51°F 47°F ♻️ Active ~14 weeks
Aug 53°F 48°F ♻️ Active ~14 weeks
Sep 45°F 46°F 🐢 Slow ~24 weeks
Oct 32°F 35°F ❄️ Dormant ~36 weeks
Nov 16°F 23°F ❄️ Dormant ~36 weeks
Dec 4°F 13°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 Fallon County

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

Quick context: Pest pressure scales with warmth and humidity. Hot humid Fallon County sees year-round bugs and fungal disease; cold dry regions see almost none. A high pest score means crop rotation, resistant varieties, and a weekly pest-watch routine from day one.

Insect Pest Pressure

4.3 / 10

Moderate — common pests appear but manageable with monitoring.

Disease Risk

2.4 / 10

Low disease risk — dry conditions reduce fungal problems.

Seasonal Risk

Spring Low
Summer High
Fall Low
Winter Low
View 5 common pests in your area
PestRisk LevelPeak Months
Aphids Moderate May, Jun, Jul, Aug
Cabbage worms Low Jun, Jul, Aug
Colorado potato beetle Low Jun, Jul
Flea beetles Moderate May, Jun, Jul
Slugs Low May, 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 Fallon County

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

For new gardeners: Why not just leave bare soil? Weed seeds, erosion, nutrient leaching, and crust formation. A cover crop solves all of these for the cost of seeds and one mowing.

Spring Cover Crops (2 options) — Build soil before the main growing season
Crop Plant By Terminate N-Fixing Soil Benefit
Buckwheat May 24 Jul 19 Rapid growth, attracts pollinators, suppresses weeds
White clover Apr 25 Jul 26 ✓ 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 2 Aug 23 Deep roots break compaction, attract pollinators and beneficial insects
Fall Cover Crops (5 options) — Plant after harvest to protect soil over winter
Crop Plant By Terminate N-Fixing Soil Benefit
Daikon radish Aug 2 Apr 29 Deep taproot breaks compaction, excellent for clay soils
Hairy vetch Jul 8 May 6 ✓ Yes Excellent nitrogen fixer, good for depleted soils
Oats Aug 16 May 6 Quick biomass, winterkills in cold zones — no spring tillage needed
Winter rye Jun 11 May 6 Suppresses weeds, prevents erosion, breaks up compacted soil
Winter wheat Jun 20 Apr 29 Erosion control, weed suppression, good biomass

Wind & Microclimate in Fallon County

The practical takeaway: Wind dries soil, knocks over young transplants, and disrupts pollination for bees and butterflies. Fallon County averages 11.8 mph — above 10 mph means windbreaks (shrubs, fences, taller crops to windward), staked tomatoes from day one, and an extra round of watering during dry windy spells. Lower wind = lower water bills and fewer broken stems.

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

Seasonal Wind Speed

Spring: 14 mph   Summer: 12 mph

Fall: 13 mph   Winter: 14 mph

Prevailing wind: W. Windy area — plant a windbreak hedge on the W side of your garden.

Windbreak Benefit

6.9/10

Moderately beneficial — a simple fence or trellis can protect delicate crops from wind stress.

Frost Pocket Risk

High

Hilly terrain with 2,920 ft of elevation range — cold air pools in low spots. Avoid planting frost-sensitive crops in valleys.

Rainwater Harvesting in Fallon County

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

What this means for you: Rainwater is unchlorinated, unfluoridated, and at ambient temperature — plants actually prefer it. Fallon County's 20" annual rainfall means even a small 50-gallon barrel catches enough for a few weeks of garden watering between storms.

Annual Collection

9,868 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

Unrestricted

Rainwater harvesting is fully legal in your state with no restrictions.

Best Collection Months

Mar, Apr, May, Aug

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 19.8 inches of rain per year
  • A 1,000 sq ft roof can collect roughly 9,868 gallons annually
  • Rainwater harvesting is fully legal in your state
  • 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 Fallon County

Soil Type

Loam

Soil pH 6.2–8.3 · 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

123-day frost-free season

A short season means indoor starts are critical for warm-season crops. Prioritise cold-hardy, fast-maturing varieties and use row covers to extend autumn harvests.

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 Fallon County

95 vegetables that grow well in Zone 4b with planting dates for Fallon County.

Show all 95 vegetables with planting dates
Plant Start Indoors Direct Sow Transplant Fall Plant Harvest Days to Maturity
Acorn Squash Apr 8 Jun 3 Jun 10 Sep 2 – Oct 7 80–100
Amaranth Mar 18 Jun 3 Jun 10 Sep 9 – Oct 28 90–120
Arugula Apr 8 May 13 May 20 Jun 28 Jun 24 – Aug 26 30–50
Asparagus Jun 3 730–1095
Beets May 13 Jun 28 Jul 8 – Aug 5 50–70
Belgian Endive Apr 8 May 13 May 20 Jun 28 Sep 9 – Oct 14 110–150
Black Beans Jun 3 Sep 2 – Oct 21 90–120
Bok Choy Apr 8 May 13 May 20 Jun 28 Jul 1 – Aug 5 40–60
Broccoli Apr 8 May 13 May 20 Jun 28 Jul 22 – Sep 2 60–90
Broccoli Rabe Apr 8 May 13 May 20 Jun 28 Jul 1 – Aug 5 40–60
Brussels Sprouts Apr 8 May 13 May 20 Jun 28 Aug 19 – Oct 14 90–130
Butternut Squash Apr 8 Jun 3 Jun 10 Sep 9 – Oct 14 85–110
Cabbage Apr 8 May 13 May 20 Jun 28 Jul 22 – Sep 16 60–100
Carrots May 13 Jun 28 Jul 15 – Aug 19 60–80
Cauliflower Apr 8 May 13 May 20 Jun 28 Jul 15 – Sep 16 55–100
Celeriac Apr 8 May 13 May 20 Jun 28 Sep 2 – Oct 7 100–120
Celery Apr 8 May 13 May 20 Jun 28 Aug 12 – Oct 7 80–120
Celtuce Apr 8 May 13 May 20 Jun 28 Jul 22 – Sep 2 60–90
Chard Apr 8 May 13 May 20 Jun 28 Jul 15 – Sep 2 50–60
Chickpeas Apr 8 May 13 May 20 Jun 28 Aug 12 – Sep 23 80–110
Chicory Apr 8 May 13 May 20 Jun 28 Jul 22 – Sep 2 60–85
Chinese Cabbage Apr 8 May 13 May 20 Jun 28 Jul 15 – Aug 12 50–70
Christmas Lima Beans Mar 18 Jun 3 Jun 10 Sep 2 – Oct 7 80–100
Collard Greens Apr 8 May 13 May 20 Jun 28 Jul 15 – Sep 16 55–75
Corn Jun 3 Aug 5 – Sep 30 60–100
Cress Apr 8 May 13 May 20 Jun 28 Jun 3 – Jun 24 14–21
Crookneck Squash Apr 8 Jun 3 Jun 10 Jul 29 – Aug 26 45–60
Crosne May 13 Jun 28 Oct 14 – Oct 7 150–200
Cucumber Apr 8 Jun 3 Jun 10 Aug 5 – Sep 30 50–70
Daikon May 13 Jun 28 Jul 8 – Aug 5 50–70
Delicata Squash Apr 8 Jun 3 Jun 10 Sep 2 – Oct 7 80–100
Edamame Jun 3 Aug 19 – Sep 30 75–100
Endive Apr 8 May 13 May 20 Jun 28 Jul 8 – Aug 12 45–65
Escarole Apr 8 May 13 May 20 Jun 28 Jul 15 – Aug 12 50–70
Fava Beans Apr 8 May 13 May 20 Jun 28 Aug 5 – Sep 16 75–100
Fennel Mar 18 Jun 3 Jun 10 Aug 12 – Sep 23 60–90
Garlic Aug 9 Nov 8 – Jan 3 90–240
Green Beans Jun 3 Jul 29 – Sep 23 50–65
Horseradish Jun 3 Oct 7 – Oct 28 120–180
Hubbard Squash Apr 8 Jun 3 Jun 10 Sep 23 – Oct 28 100–120
Kabocha Apr 8 Jun 3 Jun 10 Sep 9 – Oct 7 85–100
Kai Lan Apr 8 May 13 May 20 Jun 28 Jul 8 – Aug 5 45–60
Kale Apr 8 May 13 May 20 Jun 28 Jul 15 – Sep 9 50–70
Kidney Beans Jun 3 Sep 2 – Oct 7 85–110
Kohlrabi Apr 8 May 13 May 20 Jun 28 Jul 8 – Aug 12 45–65
Komatsuna Apr 8 May 13 May 20 Jun 28 Jun 24 – Jul 29 35–50
Leeks Apr 8 May 13 May 20 Jun 28 Aug 19 – Oct 14 90–150
Lentils Apr 8 May 13 May 20 Jun 28 Aug 12 – Sep 23 80–110
Lettuce Apr 8 May 13 May 20 Jun 28 Jun 24 – Sep 2 30–60
Lima Beans Jun 3 Aug 5 – Sep 16 60–90
Mache Apr 8 May 13 May 20 Jun 28 Jul 1 – Aug 5 40–60
Melon Apr 8 Jun 3 Jun 10 Aug 19 – Oct 7 70–100
Microgreens Apr 8 May 13 May 20 Jun 28 May 27 – Jun 24 7–21
Mitsuba Apr 8 May 13 May 13 Jun 28 Jul 8 – Sep 2 50–70
Mizuna Apr 8 May 13 May 20 Jun 28 Jun 24 – Jul 22 30–45
Mustard Greens Apr 8 May 13 May 20 Jun 28 Jun 24 – Aug 26 30–50
Napa Cabbage Apr 8 May 13 May 20 Jun 28 Jul 15 – Aug 19 55–75
Onion Apr 8 May 13 May 20 Jun 28 Aug 19 – Oct 7 90–120
Pac Choi Apr 8 May 13 May 20 Jun 28 Jul 1 – Jul 29 40–55
Parsnip May 13 Jun 28 Aug 26 – Oct 7 100–130
Patty Pan Squash Apr 8 Jun 3 Jun 10 Jul 29 – Aug 26 45–60
Peas Apr 8 May 13 May 20 Jun 28 Jul 15 – Sep 9 55–70
Peppers Mar 4 Jun 3 Jun 10 Aug 12 – Oct 21 60–90
Pole Beans Mar 18 Jun 3 Jun 10 Aug 5 – Sep 30 55–70
Potatoes Mar 18 Jun 3 Jun 10 Aug 19 – Oct 28 70–120
Pumpkin Apr 8 Jun 3 Jun 10 Sep 9 – Oct 28 85–120
Purslane Apr 8 May 13 May 20 Jun 28 Jul 1 – Aug 5 40–60
Radicchio Apr 8 May 13 May 20 Jun 28 Jul 22 – Aug 26 60–80
Radish May 13 Jun 28 Jun 10 – Jul 1 22–35
Rhubarb Jun 17 365–730
Romanesco Apr 8 May 13 May 20 Jun 28 Aug 5 – Sep 16 75–100
Rutabaga May 13 Jun 28 Aug 5 – Sep 9 80–100
Salsify May 13 Jun 28 Aug 26 – Oct 7 100–130
Savoy Cabbage Apr 8 May 13 May 20 Jun 28 Jul 29 – Sep 23 70–110
Scallions Apr 8 May 13 May 20 Jun 28 Jul 15 – Aug 12 50–70
Scarlet Runner Beans Mar 18 Jun 3 Jun 10 Aug 12 – Sep 16 60–80
Shallot Apr 8 May 13 May 20 Jun 28 Aug 19 – Oct 7 90–120
Shiso Mar 25 May 27 Jun 10 Aug 5 – Sep 30 50–70
Snap Peas Mar 18 Jun 3 Jun 10 Aug 5 – Sep 30 55–70
Snow Peas Apr 8 May 13 May 20 Jun 28 Jul 15 – Sep 9 50–65
Soybeans Jun 3 Aug 26 – Oct 21 80–120
Spaghetti Squash Apr 8 Jun 3 Jun 10 Sep 9 – Oct 7 85–100
Spinach Apr 8 May 13 May 20 Jun 28 Jun 24 – Aug 26 35–50
Squash (Summer) Apr 8 Jun 3 Jun 10 Jul 29 – Sep 30 45–65
Squash (Winter) Apr 8 Jun 3 Jun 10 Sep 2 – Oct 28 80–120
Sunchoke Jun 3 Sep 23 – Oct 28 110–150
Sweet Corn Jun 3 Aug 5 – Sep 16 60–90
Tatsoi Apr 8 May 13 May 20 Jun 28 Jun 24 – Jul 29 35–50
Tomatillo Mar 18 Jun 3 Jun 10 Aug 12 – Oct 21 60–85
Tomatoes Mar 18 Jun 3 Jun 10 Aug 12 – Oct 21 60–85
Turnip May 13 Jun 28 Jun 24 – Jul 29 40–60
Watercress Apr 8 May 13 May 20 Jun 28 Jul 1 – Aug 5 40–60
Watermelon Apr 8 Jun 3 Jun 10 Aug 19 – Oct 7 70–100
Wax Beans Jun 3 Jul 29 – Sep 23 50–65
Zucchini Apr 8 Jun 3 Jun 10 Jul 29 – Sep 23 45–60

🍓 Fruits to Grow in Fallon County

22 fruits that grow well in Zone 4b with planting dates for Fallon County.

Show all 22 fruits with planting dates
Plant Start Indoors Direct Sow Transplant Fall Plant Harvest Days to Maturity
Alpine Strawberries Jun 17 Sep 16 – Nov 11 90–180
Aronia Jun 17 730–1095
Blueberries Jun 17 730–1095
Cantaloupe Jun 17 Aug 26 – Sep 30 70–90
Cranberries Jun 17 730–1095
Currants Jun 17 730–1095
Elderberries Jun 17 730–1095
Goji Berries Jun 17 730–1095
Gooseberries Jun 17 730–1095
Grapes Jun 17 730–1095
Ground Cherry Jun 17 Aug 26 – Oct 21 65–80
Hardy Kiwi Jun 17 1095–1825
Haskaps Jun 17 730–1095
Honeydew Jun 17 Sep 9 – Oct 21 80–110
Jostaberry Jun 17 730–1095
Lingonberries Jun 17 730–1095
Medlar Jun 17 1095–1825
Mulberries Jun 17 730–1825
Persimmon Jun 17 1095–2555
Raspberries Jun 17 365–730
Serviceberries Jun 17 730–1095
Strawberries Jun 17 Sep 16 – Nov 11 90–365

🌿 Herbs to Grow in Fallon County

30 herbs that grow well in Zone 4b with planting dates for Fallon County.

Show all 30 herbs with planting dates
Plant Start Indoors Direct Sow Transplant Fall Plant Harvest Days to Maturity
Angelica Apr 8 May 13 May 13 Jun 28 365–730
Anise Apr 8 May 13 May 13 Jun 28 Aug 12 – Oct 7 90–120
Basil Mar 25 May 27 Jun 10 Aug 5 – Oct 7 50–75
Bee Balm May 27 Aug 26 – Oct 21 90–120
Borage Apr 8 May 13 May 13 Jun 28 Jul 8 – Aug 26 50–60
Caraway Apr 8 May 13 May 13 Jun 28 365–450
Catnip May 27 Jul 29 – Sep 30 60–80
Chamomile Apr 8 May 13 May 13 Jun 28 Jul 15 – Sep 23 60–90
Chervil Apr 8 May 13 May 13 Jun 28 Jun 24 – Aug 26 40–60
Chives May 27 Jul 29 – Oct 7 60–90
Cilantro Apr 8 May 13 May 13 Jun 28 Jun 24 – Aug 26 40–60
Comfrey May 27 Jul 29 – Oct 7 60–90
Dill Apr 8 May 13 May 13 Jun 28 Jun 24 – Aug 26 40–60
Fennel (herb) Apr 8 May 13 May 13 Jun 28 Jul 15 – Sep 23 60–90
Garlic Chives May 27 Jul 29 – Oct 7 60–90
Horehound May 27 Aug 12 – Oct 7 75–90
Hyssop May 27 Aug 5 – Oct 7 70–90
Lemon Balm May 27 Jul 29 – Sep 16 60–70
Lovage May 27 Aug 5 – Oct 7 70–90
Mint May 27 Jul 29 – Oct 7 60–90
Oregano May 27 Jul 29 – Oct 7 60–90
Parsley Apr 8 May 13 May 13 Jun 28 Jul 15 – Sep 16 60–80
Rue May 27 Aug 5 – Oct 7 70–90
Sage May 27 Aug 12 – Oct 7 75–90
Savory May 27 Jul 22 – Sep 16 50–70
Sorrel Apr 8 May 13 May 13 Jun 28 Jun 24 – Aug 26 40–60
Tarragon May 27 Jul 29 – Oct 7 60–90
Thai Basil Mar 25 May 27 Jun 10 Aug 5 – Oct 7 50–75
Thyme May 27 Aug 5 – Oct 7 70–90
Valerian May 27 Sep 30 – Oct 21 120–180

🌸 Flowers to Grow in Fallon County

49 flowers that grow well in Zone 4b with planting dates for Fallon County.

Show all 49 flowers with planting dates
Plant Start Indoors Direct Sow Transplant Fall Plant Bloom Days to Maturity
Ageratum Apr 1 May 27 May 27 Jul 22 – Oct 7 60–75
Alliums Aug 9 Sep 13 – Oct 11 28–42
Astilbe Mar 11 Jun 3 Aug 26 – Oct 21 70–100
Bachelor's Button Apr 1 May 6 May 20 Jul 22 – Sep 23 60–90
Begonias Mar 4 May 27 Aug 5 – Oct 14 70–90
Black-eyed Susan Mar 11 May 20 Jun 3 Aug 26 – Nov 11 60–80
Bleeding Hearts Mar 11 Jun 3 Jul 29 – Sep 9 60–90
Calendula Apr 1 May 6 May 20 Jul 8 – Sep 23 50–70
Celosia Apr 15 Jun 3 Jun 3 Aug 5 – Oct 21 60–90
Columbine Mar 11 Jun 3 Jun 3 Jul 29 – Sep 16 70–100
Coreopsis Mar 11 May 27 Jun 3 Aug 19 – Nov 11 60–80
Cosmos Apr 22 May 27 May 27 Aug 5 – Oct 28 60–90
Crocus Aug 9 Jun 14 – Jul 12 10–20
Daffodils Aug 9 Jun 21 – Jul 19 20–40
Dahlias Apr 22 Jun 3 Jun 3 Sep 2 – Nov 11 70–120
Daylily Mar 11 Jun 3 Sep 2 – Nov 11 60–90
Dianthus Mar 18 Apr 29 May 13 Jul 1 – Sep 9 60–80
Echinacea (Purple Coneflower) Mar 11 Jun 3 Jun 3 Sep 2 – Nov 11 70–90
Foxglove Mar 11 Jun 3 Jun 3 Jul 29 – Sep 9 80–120
Gaillardia (Blanket Flower) Mar 25 Jun 3 Jun 3 Aug 12 – Nov 18 70–100
Geraniums Mar 4 May 27 Aug 5 – Oct 14 70–100
Gladiolus May 27 May 27 Aug 26 – Nov 4 70–100
Hostas Mar 4 Jun 3 Sep 2 – Nov 11 60–90
Hyacinths Aug 9 Jul 12 – Aug 2 14–28
Hydrangeas Mar 4 Jun 3 Aug 26 – Oct 28 90–150
Impatiens Mar 18 Jun 3 Aug 19 – Oct 21 60–75
Irises Division Jun 3 Jul 29 – Sep 2 60–100
Larkspur Apr 22 Jul 1 – Aug 19 60–90
Lilies Division Jun 3 Aug 26 – Oct 28 70–120
Lobelia Mar 11 May 20 Jul 15 – Sep 16 70–80
Lupine Mar 11 Jun 3 Jun 3 Jul 29 – Sep 9 75–100
Marigolds Apr 8 May 27 May 27 Jul 22 – Oct 7 50–70
Nasturtium Apr 22 May 27 May 27 Jul 22 – Oct 14 55–65
Pansy Mar 4 May 20 Jul 15 – Sep 2 70–90
Peonies Division Jun 3 Aug 12 – Sep 16 90–120
Petunia Mar 18 May 27 Aug 5 – Oct 21 70–90
Phlox Mar 11 Jun 3 Jun 3 Aug 26 – Nov 4 80–110
Portulaca Apr 15 Jun 3 Jun 3 Jul 22 – Oct 7 50–70
Roses Mar 4 Jun 3 Aug 26 – Nov 11 90–180
Salvia Mar 18 May 27 Aug 5 – Oct 14 70–90
Sedum (Stonecrop) Mar 11 Jun 3 Oct 7 – Dec 2 60–90
Snapdragon Mar 11 May 20 Jul 29 – Sep 23 70–100
Sunflower Apr 29 May 27 May 27 Aug 19 – Oct 21 70–100
Sweet Alyssum Apr 1 May 13 May 20 Jul 1 – Sep 2 45–60
Sweet Pea Apr 8 Apr 15 May 20 Aug 12 – Sep 30 65–85
Tulips Aug 9 Jul 5 – Jul 26 15–30
Vinca (Annual) Mar 4 Jun 3 Aug 12 – Oct 21 70–90
Yarrow Mar 11 May 20 Jun 3 Aug 19 – Nov 11 60–90
Zinnia Apr 22 May 27 May 27 Aug 5 – Oct 21 60–70

Monthly Planting Guide for Fallon County

Gardening Guides & Resources

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

Frequently Asked Questions

What planting zone is Fallon County, MT?

Fallon County is in USDA Hardiness Zone 4b. 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 Fallon County, MT?

Based on 31 years of NOAA weather station data, the median last spring frost in Fallon County falls around May 20. In 8 out of 10 years, last frost lands between May 10 and June 8 — a 29-day window of variability. Use June 8 as your conservative safe-to-plant date for frost-sensitive crops.

When is the first fall frost in Fallon County, MT?

The median first fall frost in Fallon County arrives around September 20. In cold years it can arrive as early as September 5; in mild years as late as October 4. Harvest or protect frost-sensitive crops — tomatoes, peppers, basil, squash — before this date.

How long is the growing season in Fallon County?

Fallon County has a frost-free growing season of approximately 123 days. Focus on short-season varieties and start warm-season crops indoors 6–8 weeks before last frost.

What is the soil like in Fallon County for gardening?

Fallon County has predominantly Loam soil with a pH range of 6.2–8.3 and Well Drained drainage. Most vegetables and herbs grow well with standard composting and seasonal soil amendment.

What is grown commercially in Fallon County?

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

Is Fallon County a good location for home gardening?

Fallon 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 Fallon County (Zone 4b). 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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Composting Guide for Homesteaders

Composting Guide for Homesteaders

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Turn kitchen scraps and yard waste into compost that actually feeds the garden — instead of a pile that smells, attracts pests, and never breaks down.

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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 Fallon 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.