Carbon County, MT — Planting Guide
Carbon County is in USDA Zone 5a. The average last spring frost is May 13 and the first fall frost is September 28, giving you a growing season of approximately 138 days.
At an elevation of 5,849 ft, Carbon County receives approximately 23.3 in of rainfall annually. Summer highs average 83°F with winter lows around 5°F. The predominant soil type is Loam.
🌡️ Zone
5a (-20°F to -15°F min)
❄️ Last Frost
May 13
🍂 First Frost
September 28
📅 Growing Season
138 days
⛰️ Elevation
5,849 ft
🌧️ Annual Rainfall
23.3 in
Carbon County, MT
Short season
138 days
Last Spring Frost
May 13
➔
138 growing days
➔
First Fall Frost
September 28
Carbon County Soil Profile
Soil Type
Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Zone 5a
Frost Countdown
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Last Frost: May 13
First Frost: Sep 28
Soil & Growing Conditions in Carbon County
Soil Type
Loam
Ideal for most crops — holds moisture and nutrients while draining well.
Watering Needs
With 23.3 inches annually, regular irrigation is essential. Drip systems and heavy mulching conserve water.
Season Tips
138-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.
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 Carbon County
105 vegetables that grow well in Zone 5a with planting dates for Carbon County.
Show all 105 vegetables with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Fall Plant | Harvest | Days to Maturity |
|---|---|---|---|---|---|---|
| Acorn Squash | Apr 8 | May 20 | May 27 | — | Aug 19 – Sep 23 | 80–100 |
| Amaranth | Mar 18 | May 20 | May 27 | — | Aug 26 – Oct 14 | 90–120 |
| Arugula | Apr 8 | Apr 29 | May 13 | Jul 20 | Jun 17 – Aug 19 | 30–50 |
| Asparagus | — | — | May 27 | — | — | 730–1095 |
| Beets | — | Apr 29 | — | Jul 20 | Jun 24 – Jul 22 | 50–70 |
| Belgian Endive | Apr 8 | Apr 29 | May 13 | Jul 20 | Sep 2 – Oct 28 | 110–150 |
| Bitter Melon | Mar 18 | May 20 | May 27 | — | Jul 29 – Sep 9 | 60–90 |
| Black Beans | — | May 20 | — | — | Aug 19 – Oct 7 | 90–120 |
| Bok Choy | Apr 8 | Apr 29 | May 13 | Jul 20 | Jun 24 – Jul 29 | 40–60 |
| Broccoli | Apr 8 | Apr 29 | May 13 | Jul 20 | Jul 15 – Aug 26 | 60–90 |
| Broccoli Rabe | Apr 8 | Apr 29 | May 13 | Jul 20 | Jun 24 – Jul 29 | 40–60 |
| Brussels Sprouts | Apr 8 | Apr 29 | May 13 | Jul 20 | Aug 12 – Oct 7 | 90–130 |
| Butternut Squash | Apr 8 | May 20 | May 27 | — | Aug 26 – Sep 30 | 85–110 |
| Cabbage | Apr 8 | Apr 29 | May 13 | Jul 20 | Jul 15 – Sep 9 | 60–100 |
| Calabash | Mar 18 | May 20 | May 27 | — | Aug 19 – Oct 14 | 80–120 |
| Carrots | — | Apr 29 | — | Jul 20 | Jul 1 – Aug 5 | 60–80 |
| Cauliflower | Apr 8 | Apr 29 | May 13 | Jul 20 | Jul 8 – Sep 9 | 55–100 |
| Celeriac | Apr 8 | Apr 29 | May 13 | Jul 20 | Aug 26 – Sep 30 | 100–120 |
| Celery | Apr 8 | Apr 29 | May 13 | Jul 20 | Aug 5 – Sep 30 | 80–120 |
| Celtuce | Apr 8 | Apr 29 | May 13 | Jul 20 | Jul 15 – Aug 26 | 60–90 |
| Chard | Apr 8 | Apr 29 | May 13 | Jul 20 | Jul 8 – Aug 26 | 50–60 |
| Chickpeas | Apr 8 | Apr 29 | May 13 | Jul 20 | Aug 5 – Sep 16 | 80–110 |
| Chicory | Apr 8 | Apr 29 | May 13 | Jul 20 | Jul 15 – Aug 26 | 60–85 |
| Chinese Cabbage | Apr 8 | Apr 29 | May 13 | Jul 20 | Jul 8 – Aug 5 | 50–70 |
| Christmas Lima Beans | Mar 18 | May 20 | May 27 | — | Aug 19 – Sep 23 | 80–100 |
| Collard Greens | Apr 8 | Apr 29 | May 13 | Jul 20 | Jul 8 – Sep 9 | 55–75 |
| Corn | — | May 20 | — | — | Jul 22 – Sep 16 | 60–100 |
| Cowpeas | — | May 20 | — | — | Jul 22 – Sep 2 | 60–90 |
| Cress | Apr 8 | Apr 29 | May 13 | Jul 20 | May 27 – Jun 17 | 14–21 |
| Crookneck Squash | Apr 8 | May 20 | May 27 | — | Jul 15 – Aug 12 | 45–60 |
| Crosne | — | Apr 29 | — | Jul 20 | Sep 30 – Oct 14 | 150–200 |
| Cucumber | Apr 8 | May 20 | May 27 | — | Jul 22 – Sep 16 | 50–70 |
| Daikon | — | Apr 29 | — | Jul 20 | Jun 24 – Jul 22 | 50–70 |
| Delicata Squash | Apr 8 | May 20 | May 27 | — | Aug 19 – Sep 23 | 80–100 |
| Edamame | — | May 20 | — | — | Aug 5 – Sep 16 | 75–100 |
| Eggplant | Mar 4 | May 20 | May 27 | — | Aug 5 – Oct 7 | 65–85 |
| Endive | Apr 8 | Apr 29 | May 13 | Jul 20 | Jul 1 – Aug 5 | 45–65 |
| Escarole | Apr 8 | Apr 29 | May 13 | Jul 20 | Jul 8 – Aug 5 | 50–70 |
| Fava Beans | Apr 8 | Apr 29 | May 13 | Jul 20 | Jul 29 – Sep 9 | 75–100 |
| Fennel | Mar 18 | May 20 | May 27 | — | Jul 29 – Sep 9 | 60–90 |
| Garlic | — | — | — | Aug 17 | Nov 16 – Feb 1 | 90–240 |
| Green Beans | — | May 20 | — | — | Jul 15 – Sep 9 | 50–65 |
| Horseradish | — | — | May 27 | — | Sep 30 – Nov 11 | 120–180 |
| Hot Peppers | Mar 4 | May 20 | May 27 | — | Aug 5 – Nov 11 | 70–120 |
| Hubbard Squash | Apr 8 | May 20 | May 27 | — | Sep 9 – Oct 14 | 100–120 |
| Kabocha | Apr 8 | May 20 | May 27 | — | Aug 26 – Sep 23 | 85–100 |
| Kai Lan | Apr 8 | Apr 29 | May 13 | Jul 20 | Jul 1 – Jul 29 | 45–60 |
| Kale | Apr 8 | Apr 29 | May 13 | Jul 20 | Jul 8 – Sep 2 | 50–70 |
| Kidney Beans | — | May 20 | — | — | Aug 19 – Sep 23 | 85–110 |
| Kohlrabi | Apr 8 | Apr 29 | May 13 | Jul 20 | Jul 1 – Aug 5 | 45–65 |
| Komatsuna | Apr 8 | Apr 29 | May 13 | Jul 20 | Jun 17 – Jul 22 | 35–50 |
| Leeks | Apr 8 | Apr 29 | May 13 | Jul 20 | Aug 12 – Oct 28 | 90–150 |
| Lentils | Apr 8 | Apr 29 | May 13 | Jul 20 | Aug 5 – Sep 16 | 80–110 |
| Lettuce | Apr 8 | Apr 29 | May 13 | Jul 20 | Jun 17 – Aug 26 | 30–60 |
| Lima Beans | — | May 20 | — | — | Jul 22 – Sep 2 | 60–90 |
| Mache | Apr 8 | Apr 29 | May 13 | Jul 20 | Jun 24 – Jul 29 | 40–60 |
| Melon | Apr 8 | May 20 | May 27 | — | Aug 5 – Sep 23 | 70–100 |
| Microgreens | Apr 8 | Apr 29 | May 13 | Jul 20 | May 20 – Jun 17 | 7–21 |
| Mitsuba | Apr 8 | Apr 29 | May 6 | Jul 20 | Jul 1 – Aug 26 | 50–70 |
| Mizuna | Apr 8 | Apr 29 | May 13 | Jul 20 | Jun 17 – Jul 15 | 30–45 |
| Mustard Greens | Apr 8 | Apr 29 | May 13 | Jul 20 | Jun 17 – Aug 19 | 30–50 |
| Napa Cabbage | Apr 8 | Apr 29 | May 13 | Jul 20 | Jul 8 – Aug 12 | 55–75 |
| New Zealand Spinach | Mar 18 | May 20 | May 27 | — | Jul 22 – Aug 19 | 55–70 |
| Okra | Mar 18 | May 20 | May 27 | — | Jul 22 – Sep 16 | 50–65 |
| Onion | Apr 8 | Apr 29 | May 13 | Jul 20 | Aug 12 – Sep 30 | 90–120 |
| Pac Choi | Apr 8 | Apr 29 | May 13 | Jul 20 | Jun 24 – Jul 22 | 40–55 |
| Parsnip | — | Apr 29 | — | Jul 20 | Aug 12 – Sep 23 | 100–130 |
| Patty Pan Squash | Apr 8 | May 20 | May 27 | — | Jul 15 – Aug 12 | 45–60 |
| Peas | Apr 8 | Apr 29 | May 13 | Jul 20 | Jul 8 – Sep 2 | 55–70 |
| Peppers | Mar 4 | May 20 | May 27 | — | Jul 29 – Oct 7 | 60–90 |
| Pole Beans | Mar 18 | May 20 | May 27 | — | Jul 22 – Sep 16 | 55–70 |
| Potatoes | Mar 18 | May 20 | May 27 | — | Aug 5 – Oct 14 | 70–120 |
| Pumpkin | Apr 8 | May 20 | May 27 | — | Aug 26 – Oct 14 | 85–120 |
| Purslane | Apr 8 | Apr 29 | May 13 | Jul 20 | Jun 24 – Jul 29 | 40–60 |
| Radicchio | Apr 8 | Apr 29 | May 13 | Jul 20 | Jul 15 – Aug 19 | 60–80 |
| Radish | — | Apr 29 | — | Jul 20 | May 27 – Jun 17 | 22–35 |
| Rhubarb | — | — | Jun 3 | — | — | 365–730 |
| Romanesco | Apr 8 | Apr 29 | May 13 | Jul 20 | Jul 29 – Sep 9 | 75–100 |
| Rutabaga | — | Apr 29 | — | Jul 20 | Jul 22 – Aug 26 | 80–100 |
| Salsify | — | Apr 29 | — | Jul 20 | Aug 12 – Sep 23 | 100–130 |
| Savoy Cabbage | Apr 8 | Apr 29 | May 13 | Jul 20 | Jul 22 – Sep 16 | 70–110 |
| Scallions | Apr 8 | Apr 29 | May 13 | Jul 20 | Jul 8 – Aug 5 | 50–70 |
| Scarlet Runner Beans | Mar 18 | May 20 | May 27 | — | Jul 29 – Sep 2 | 60–80 |
| Shallot | Apr 8 | Apr 29 | May 13 | Jul 20 | Aug 12 – Sep 30 | 90–120 |
| Shiso | Mar 25 | May 20 | May 27 | — | Jul 22 – Sep 16 | 50–70 |
| Snap Peas | Mar 18 | May 20 | May 27 | — | Jul 22 – Sep 16 | 55–70 |
| Snow Peas | Apr 8 | Apr 29 | May 13 | Jul 20 | Jul 8 – Sep 2 | 50–65 |
| Soybeans | — | May 20 | — | — | Aug 12 – Oct 7 | 80–120 |
| Spaghetti Squash | Apr 8 | May 20 | May 27 | — | Aug 26 – Sep 23 | 85–100 |
| Spinach | Apr 8 | Apr 29 | May 13 | Jul 20 | Jun 17 – Aug 19 | 35–50 |
| Squash (Summer) | Apr 8 | May 20 | May 27 | — | Jul 15 – Sep 16 | 45–65 |
| Squash (Winter) | Apr 8 | May 20 | May 27 | — | Aug 19 – Oct 14 | 80–120 |
| Sunchoke | — | — | May 27 | — | Sep 16 – Nov 11 | 110–150 |
| Sweet Corn | — | May 20 | — | — | Jul 22 – Sep 2 | 60–90 |
| Sweet Potatoes | Mar 18 | May 20 | May 27 | — | Aug 26 – Oct 14 | 90–120 |
| Tatsoi | Apr 8 | Apr 29 | May 13 | Jul 20 | Jun 17 – Jul 22 | 35–50 |
| Tomatillo | Mar 18 | May 20 | May 27 | — | Jul 29 – Oct 7 | 60–85 |
| Tomatoes | Mar 18 | May 20 | May 27 | — | Jul 29 – Oct 7 | 60–85 |
| Turnip | — | Apr 29 | — | Jul 20 | Jun 10 – Jul 15 | 40–60 |
| Watercress | Apr 8 | Apr 29 | May 13 | Jul 20 | Jun 24 – Jul 29 | 40–60 |
| Watermelon | Apr 8 | May 20 | May 27 | — | Aug 5 – Sep 23 | 70–100 |
| Wax Beans | — | May 20 | — | — | Jul 15 – Sep 9 | 50–65 |
| Winter Melon | Mar 18 | May 20 | May 27 | — | Aug 26 – Oct 14 | 90–120 |
| Yard Long Beans | Mar 18 | May 20 | May 27 | — | Jul 22 – Sep 2 | 55–80 |
| Zucchini | Apr 8 | May 20 | May 27 | — | Jul 15 – Sep 9 | 45–60 |
🍓 Fruits to Grow in Carbon County
27 fruits that grow well in Zone 5a with planting dates for Carbon County.
Show all 27 fruits with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Fall Plant | Harvest | Days to Maturity |
|---|---|---|---|---|---|---|
| Alpine Strawberries | — | — | Jun 3 | — | Sep 2 – Nov 18 | 90–180 |
| Aronia | — | — | Jun 3 | — | — | 730–1095 |
| Blackberries | — | — | Jun 3 | — | — | 365–730 |
| Blueberries | — | — | Jun 3 | — | — | 730–1095 |
| Boysenberries | — | — | Jun 3 | — | — | 365–730 |
| Cantaloupe | — | — | Jun 3 | — | Aug 12 – Sep 16 | 70–90 |
| Che Fruit | — | — | Jun 3 | — | — | 1095–1825 |
| Cranberries | — | — | Jun 3 | — | — | 730–1095 |
| Currants | — | — | Jun 3 | — | — | 730–1095 |
| Elderberries | — | — | Jun 3 | — | — | 730–1095 |
| Goji Berries | — | — | Jun 3 | — | — | 730–1095 |
| Gooseberries | — | — | Jun 3 | — | — | 730–1095 |
| Grapes | — | — | Jun 3 | — | — | 730–1095 |
| Ground Cherry | — | — | Jun 3 | — | Aug 12 – Oct 7 | 65–80 |
| Hardy Kiwi | — | — | Jun 3 | — | — | 1095–1825 |
| Haskaps | — | — | Jun 3 | — | — | 730–1095 |
| Honeydew | — | — | Jun 3 | — | Aug 26 – Oct 7 | 80–110 |
| Jostaberry | — | — | Jun 3 | — | — | 730–1095 |
| Lingonberries | — | — | Jun 3 | — | — | 730–1095 |
| Medlar | — | — | Jun 3 | — | — | 1095–1825 |
| Mulberries | — | — | Jun 3 | — | — | 730–1825 |
| Pawpaw | — | — | Jun 3 | — | — | 1095–2555 |
| Persimmon | — | — | Jun 3 | — | — | 1095–2555 |
| Quince | — | — | Jun 3 | — | — | 1095–1825 |
| Raspberries | — | — | Jun 3 | — | — | 365–730 |
| Serviceberries | — | — | Jun 3 | — | — | 730–1095 |
| Strawberries | — | — | Jun 3 | — | Sep 2 – Nov 18 | 90–365 |
🌿 Herbs to Grow in Carbon County
34 herbs that grow well in Zone 5a with planting dates for Carbon County.
Show all 34 herbs with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Fall Plant | Harvest | Days to Maturity |
|---|---|---|---|---|---|---|
| Angelica | Apr 8 | Apr 29 | May 6 | Jul 20 | — | 365–730 |
| Anise | Apr 8 | Apr 29 | May 6 | Jul 20 | Aug 5 – Oct 21 | 90–120 |
| Basil | Mar 25 | May 20 | May 27 | — | Jul 22 – Sep 23 | 50–75 |
| Bee Balm | — | — | May 20 | — | Aug 19 – Nov 4 | 90–120 |
| Borage | Apr 8 | Apr 29 | May 6 | Jul 20 | Jul 1 – Aug 19 | 50–60 |
| Caraway | Apr 8 | Apr 29 | May 6 | Jul 20 | — | 365–450 |
| Catnip | — | — | May 20 | — | Jul 22 – Sep 23 | 60–80 |
| Chamomile | Apr 8 | Apr 29 | May 6 | Jul 20 | Jul 8 – Sep 16 | 60–90 |
| Chervil | Apr 8 | Apr 29 | May 6 | Jul 20 | Jun 17 – Aug 19 | 40–60 |
| Chives | — | — | May 20 | — | Jul 22 – Sep 30 | 60–90 |
| Cilantro | Apr 8 | Apr 29 | May 6 | Jul 20 | Jun 17 – Aug 19 | 40–60 |
| Comfrey | — | — | May 20 | — | Jul 22 – Sep 30 | 60–90 |
| Cumin | Apr 8 | Apr 29 | May 6 | Jul 20 | Aug 19 – Oct 21 | 100–120 |
| Dill | Apr 8 | Apr 29 | May 6 | Jul 20 | Jun 17 – Aug 19 | 40–60 |
| Epazote | Mar 25 | May 20 | May 27 | — | Jul 15 – Sep 9 | 45–60 |
| Fennel (herb) | Apr 8 | Apr 29 | May 6 | Jul 20 | Jul 8 – Sep 16 | 60–90 |
| Feverfew | — | — | May 20 | — | Aug 19 – Nov 4 | 90–120 |
| Garlic Chives | — | — | May 20 | — | Jul 22 – Sep 30 | 60–90 |
| Horehound | — | — | May 20 | — | Aug 5 – Sep 30 | 75–90 |
| Hyssop | — | — | May 20 | — | Jul 29 – Sep 30 | 70–90 |
| Lemon Balm | — | — | May 20 | — | Jul 22 – Sep 9 | 60–70 |
| Lemon Thyme | — | — | May 20 | — | Jul 29 – Sep 30 | 70–90 |
| Lovage | — | — | May 20 | — | Jul 29 – Sep 30 | 70–90 |
| Mint | — | — | May 20 | — | Jul 22 – Sep 30 | 60–90 |
| Oregano | — | — | May 20 | — | Jul 22 – Sep 30 | 60–90 |
| Parsley | Apr 8 | Apr 29 | May 6 | Jul 20 | Jul 8 – Sep 9 | 60–80 |
| Rue | — | — | May 20 | — | Jul 29 – Sep 30 | 70–90 |
| Sage | — | — | May 20 | — | Aug 5 – Sep 30 | 75–90 |
| Savory | — | — | May 20 | — | Jul 15 – Sep 9 | 50–70 |
| Sorrel | Apr 8 | Apr 29 | May 6 | Jul 20 | Jun 17 – Aug 19 | 40–60 |
| Tarragon | — | — | May 20 | — | Jul 22 – Sep 30 | 60–90 |
| Thai Basil | Mar 25 | May 20 | May 27 | — | Jul 22 – Sep 23 | 50–75 |
| Thyme | — | — | May 20 | — | Jul 29 – Sep 30 | 70–90 |
| Valerian | — | — | May 20 | — | Sep 23 – Nov 4 | 120–180 |
🌸 Flowers to Grow in Carbon County
51 flowers that grow well in Zone 5a with planting dates for Carbon County.
Show all 51 flowers with planting dates
| Plant | Start Indoors | Direct Sow | Transplant | Fall Plant | Bloom | Days to Maturity |
|---|---|---|---|---|---|---|
| Ageratum | Mar 25 | May 20 | May 20 | — | Jul 15 – Oct 7 | 60–75 |
| Alliums | — | — | — | Aug 17 | Sep 21 – Oct 19 | 28–42 |
| Anemones | Apr 15 | — | May 13 | — | Jun 24 – Jul 22 | 90–120 |
| Astilbe | Mar 11 | — | May 27 | — | Aug 12 – Oct 14 | 70–100 |
| Bachelor's Button | Apr 1 | Apr 22 | May 13 | — | Jul 15 – Sep 23 | 60–90 |
| Begonias | Mar 4 | — | May 20 | — | Jul 29 – Oct 21 | 70–90 |
| Black-eyed Susan | Mar 11 | May 13 | May 27 | — | Aug 12 – Nov 11 | 60–80 |
| Bleeding Hearts | Mar 11 | — | May 27 | — | Jul 22 – Sep 2 | 60–90 |
| Calendula | Apr 1 | Apr 22 | May 13 | — | Jul 1 – Sep 23 | 50–70 |
| Celosia | Apr 8 | May 27 | May 27 | — | Jul 29 – Oct 28 | 60–90 |
| Columbine | Mar 11 | May 27 | May 27 | — | Jul 22 – Sep 2 | 70–100 |
| Coreopsis | Mar 11 | May 20 | May 27 | — | Aug 5 – Nov 11 | 60–80 |
| Cosmos | Apr 15 | May 20 | May 20 | — | Jul 29 – Oct 21 | 60–90 |
| Crocus | — | — | — | Aug 17 | Jun 29 – Jul 20 | 10–20 |
| Daffodils | — | — | — | Aug 17 | Jul 6 – Jul 27 | 20–40 |
| Dahlias | Apr 15 | May 20 | May 20 | — | Aug 12 – Nov 4 | 70–120 |
| Daylily | Mar 11 | — | May 27 | — | Aug 19 – Nov 11 | 60–90 |
| Dianthus | Mar 11 | Apr 15 | Apr 29 | — | Jun 17 – Sep 2 | 60–80 |
| Echinacea (Purple Coneflower) | Mar 11 | May 27 | May 27 | — | Aug 19 – Nov 11 | 70–90 |
| Foxglove | Mar 11 | May 27 | May 27 | — | Jul 22 – Sep 2 | 80–120 |
| Gaillardia (Blanket Flower) | Mar 18 | May 27 | May 27 | — | Aug 5 – Nov 25 | 70–100 |
| Geraniums | Mar 4 | — | May 20 | — | Jul 29 – Oct 21 | 70–100 |
| Gladiolus | — | May 20 | May 20 | — | Aug 12 – Nov 4 | 70–100 |
| Hostas | Mar 4 | — | May 27 | — | Aug 19 – Nov 11 | 60–90 |
| Hyacinths | — | — | — | Aug 17 | Jul 27 – Aug 24 | 14–28 |
| Hydrangeas | Mar 4 | — | May 27 | — | Aug 12 – Oct 28 | 90–150 |
| Impatiens | Mar 18 | — | May 20 | — | Jul 29 – Oct 21 | 60–75 |
| Irises | — | Division | May 27 | — | Jul 22 – Aug 26 | 60–100 |
| Larkspur | — | Apr 15 | — | — | Jun 24 – Aug 19 | 60–90 |
| Lavender | Mar 4 | — | Jun 3 | — | Aug 12 – Sep 23 | 90–120 |
| Lilies | — | Division | May 27 | — | Aug 5 – Oct 28 | 70–120 |
| Lobelia | Mar 4 | — | May 6 | — | Jul 1 – Sep 9 | 70–80 |
| Lupine | Mar 11 | May 27 | May 27 | — | Jul 22 – Sep 2 | 75–100 |
| Marigolds | Apr 1 | May 20 | May 20 | — | Jul 15 – Oct 7 | 50–70 |
| Nasturtium | Apr 15 | May 20 | May 20 | — | Jul 15 – Oct 21 | 55–65 |
| Pansy | Mar 4 | — | May 13 | — | Jul 8 – Sep 2 | 70–90 |
| Peonies | — | Division | May 27 | — | Aug 5 – Sep 16 | 90–120 |
| Petunia | Mar 18 | — | May 20 | — | Jul 29 – Oct 21 | 70–90 |
| Phlox | Mar 11 | May 27 | May 27 | — | Aug 12 – Oct 28 | 80–110 |
| Portulaca | Apr 8 | May 27 | May 27 | — | Jul 15 – Oct 14 | 50–70 |
| Roses | Mar 4 | — | May 27 | — | Aug 12 – Nov 11 | 90–180 |
| Salvia | Mar 11 | — | May 20 | — | Jul 29 – Oct 21 | 70–90 |
| Sedum (Stonecrop) | Mar 11 | — | May 27 | — | Sep 23 – Nov 25 | 60–90 |
| Snapdragon | Mar 4 | Apr 29 | May 13 | — | Jul 22 – Sep 23 | 70–100 |
| Sunflower | Apr 22 | May 20 | May 20 | — | Aug 12 – Oct 21 | 70–100 |
| Sweet Alyssum | Mar 25 | Apr 29 | May 13 | — | Jun 24 – Sep 2 | 45–60 |
| Sweet Pea | Apr 1 | Apr 8 | May 13 | — | Jul 29 – Sep 30 | 65–85 |
| Tulips | — | — | — | Aug 17 | Jul 20 – Aug 10 | 15–30 |
| Vinca (Annual) | Feb 25 | — | May 27 | — | Aug 5 – Oct 21 | 70–90 |
| Yarrow | Mar 11 | May 13 | May 27 | — | Aug 5 – Nov 11 | 60–90 |
| Zinnia | Apr 15 | May 20 | May 20 | — | Jul 29 – Oct 21 | 60–70 |
Monthly Planting Guide for Carbon County
Gardening Guides & Resources
Helpful guides from The Ultimate Homestead to improve your garden in Carbon County.
Frequently Asked Questions
What planting zone is Carbon County, MT?
Carbon County is in USDA Hardiness Zone 5a. 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 Carbon County, MT?
Based on 30 years of NOAA weather station data, the median last spring frost in Carbon County falls around May 13. Plan transplants and direct-sow dates relative to this date.
When is the first fall frost in Carbon County, MT?
The median first fall frost in Carbon County arrives around September 28. Harvest or protect frost-sensitive crops — tomatoes, peppers, basil, squash — before this date.
Your Carbon County Garden Planner — Free
A 22-page printable planner built for Carbon County (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.
The Gardener's Encyclopedia to Companion Planting
$27
$293 value
The pairings that make vegetables, herbs, and flowers grow better — and the ones that quietly wreck a bed.
- Proven pairings for 200+ vegetables, herbs, flowers, and fruits
- Full seed-starting + planting schedule with timing and spacing
- Bonus: square-foot gardening guide + printable seasonal planners
Seed Saving & Storage Guide
$27
$157 value
Most saved seeds go bad before next season. This shows exactly when to pick, how to dry, and where to store seeds from 200 plants so yours don't.
- 200 plants, step-by-step: life cycle, pollination type, isolation
- Exact temperature + humidity ranges that keep seeds viable
- Bonus: searchable Google Sheets tracker + custom GPT assistant
Composting Guide for Homesteaders
$27
$210 value
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.
- 14 sections on composting methods, soil science, and troubleshooting
- The 7-step hot-compost system from start to finish
- Bonus tools: troubleshooting chart, safety guide, monitoring log