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Zone 3b Planting Calendar

Zone 3b Zone 3b July

Zone 3b gardeners: here's your July plan

Each item below is timed to Zone 3b's frost dates and soil temperatures. Skip nothing, stress about nothing.

Avg. last frost May 16
Avg. first frost September 22
  1. Fire up the seed-starting tray: pole beans, tomatoes, and ageratum

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

  2. Bring in the carrots, green beans, and kale

    If you can't use it all right away, check the food-preservation section of your planner.

Before August arrives, get these ready
  • Starting indoors: peppers, begonias, and geraniums
  • First harvests: carrots, cucumber, and green beans
  • Fall sowing: alliums, crocus, and daffodils
Get the full Zone 3b Garden Planner — free →

Zone 3b has an average minimum temperature range of -35°F to -30°F. The average last spring frost is around May 10 and the first fall frost is around September 22, giving you approximately 135 days in the growing season.

There are 170 plants in our database that grow well in Zone 3b.

Zone 3b Short season
135 days
❄
Last Spring Frost May 10
➔ 135 growing days ➔
❄
First Fall Frost September 22
Zone 3b Frost Countdown
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Last Frost: May 10 First Frost: Sep 22

States That Include Zone 3b

Many states span multiple zones. The states highlighted below contain areas classified as Zone 3b.

AL — Zone 7b AL AR — Zone 7b AR AZ — Zone 8a AZ CA — Zone 9a CA CO — Zone 5a CO CT — Zone 6b CT DE — Zone 7a DE FL — Zone 9a FL GA — Zone 7b GA IA — Zone 5a IA ID — Zone 5b ID IL — Zone 5b IL IN — Zone 6a IN KS — Zone 6a KS KY — Zone 6b KY LA — Zone 8b LA MA — Zone 6a MA MD — Zone 7a MD ME — Zone 4b ME MI — Zone 5b MI MN — Zone 4a MN MO — Zone 6a MO MS — Zone 8a MS MT — Zone 4b MT NC — Zone 7a NC ND — Zone 3b ND NE — Zone 5a NE NH — Zone 5a NH NJ — Zone 7a NJ NM — Zone 6b NM NV — Zone 6b NV NY — Zone 5b NY OH — Zone 6a OH OK — Zone 7a OK OR — Zone 7a OR PA — Zone 6a PA RI — Zone 6b RI SC — Zone 8a SC SD — Zone 4a SD TN — Zone 7a TN TX — Zone 8a TX UT — Zone 5b UT VA — Zone 7a VA VT — Zone 4b VT WA — Zone 7a WA WI — Zone 4b WI WV — Zone 6a WV WY — Zone 4a WY AK — Zone 2a AK HI — Zone 11a HI
Zones: 1 2 3 4 5 6 7 8 9 10 11

Growing Season Comparison

What to Plant Right Now in Zone 3b

Based on July 2026 planting windows.

Ageratum Harvest Jul 19 – Sep 20 Angelica Fall Sowing Jun 30 – Jul 14 Arugula Fall Sowing Jun 30 – Jul 14 Bachelor's Button Harvest Jul 12 – Sep 6 Beets Fall Sowing Jun 30 – Jul 14 Belgian Endive Fall Sowing Jun 30 – Jul 14 Bleeding Hearts Harvest Jul 19 – Aug 30 Bok Choy Fall Sowing Jun 30 – Jul 14

See all July plantings →

All Planting Windows at a Glance

This chart shows when to start, transplant, sow, and harvest every plant in Zone 3b.

Vegetables for Zone 3b

Plant Start Indoors Direct Sow Transplant Harvest Days to Maturity
Acorn Squash Mar 29 May 24 May 31 Aug 23 – Sep 27 80–100
Amaranth Mar 8 May 24 May 31 Aug 30 – Oct 4 90–120
Arugula Mar 29 May 3 May 10 Jun 14 – Aug 16 30–50
Asparagus — — May 24 — 730–1095
Beets — May 3 — Jun 28 – Jul 26 50–70
Belgian Endive Mar 29 May 3 May 10 Aug 30 – Sep 13 110–150
Black Beans — May 24 — Aug 23 – Sep 27 90–120
Bok Choy Mar 29 May 3 May 10 Jun 21 – Jul 26 40–60
Broccoli Mar 29 May 3 May 10 Jul 12 – Aug 23 60–90
Broccoli Rabe Mar 29 May 3 May 10 Jun 21 – Jul 26 40–60
Brussels Sprouts Mar 29 May 3 May 10 Aug 9 – Sep 13 90–130
Butternut Squash Mar 29 May 24 May 31 Aug 30 – Oct 4 85–110
Cabbage Mar 29 May 3 May 10 Jul 12 – Sep 6 60–100
Carrots — May 3 — Jul 5 – Aug 9 60–80
Cauliflower Mar 29 May 3 May 10 Jul 5 – Sep 6 55–100
Celeriac Mar 29 May 3 May 10 Aug 23 – Sep 13 100–120
Celery Mar 29 May 3 May 10 Aug 2 – Sep 13 80–120
Celtuce Mar 29 May 3 May 10 Jul 12 – Aug 23 60–90
Chard Mar 29 May 3 May 10 Jul 5 – Aug 23 50–60
Chickpeas Mar 29 May 3 May 10 Aug 2 – Sep 13 80–110
Chicory Mar 29 May 3 May 10 Jul 12 – Aug 23 60–85
Chinese Cabbage Mar 29 May 3 May 10 Jul 5 – Aug 2 50–70
Collard Greens Mar 29 May 3 May 10 Jul 5 – Sep 6 55–75
Corn — May 24 — Jul 26 – Sep 20 60–100
Cress Mar 29 May 3 May 10 May 24 – Jun 14 14–21
Crookneck Squash Mar 29 May 24 May 31 Jul 19 – Aug 16 45–60
Cucumber Mar 29 May 24 May 31 Jul 26 – Sep 20 50–70
Daikon — May 3 — Jun 28 – Jul 26 50–70
Delicata Squash Mar 29 May 24 May 31 Aug 23 – Sep 27 80–100
Edamame — May 24 — Aug 9 – Sep 20 75–100
Endive Mar 29 May 3 May 10 Jun 28 – Aug 2 45–65
Escarole Mar 29 May 3 May 10 Jul 5 – Aug 2 50–70
Fava Beans Mar 29 May 3 May 10 Jul 26 – Sep 6 75–100
Garlic — — — Nov 10 – Dec 15 90–240
Green Beans — May 24 — Jul 19 – Sep 13 50–65
Horseradish — — May 24 Sep 27 120–180
Hubbard Squash Mar 29 May 24 May 31 Sep 13 – Oct 4 100–120
Kabocha Mar 29 May 24 May 31 Aug 30 – Sep 27 85–100
Kai Lan Mar 29 May 3 May 10 Jun 28 – Jul 26 45–60
Kale Mar 29 May 3 May 10 Jul 5 – Aug 30 50–70
Kidney Beans — May 24 — Aug 23 – Sep 27 85–110
Kohlrabi Mar 29 May 3 May 10 Jun 28 – Aug 2 45–65
Komatsuna Mar 29 May 3 May 10 Jun 14 – Jul 19 35–50
Leeks Mar 29 May 3 May 10 Aug 9 – Sep 13 90–150
Lentils Mar 29 May 3 May 10 Aug 2 – Sep 13 80–110
Lettuce Mar 29 May 3 May 10 Jun 14 – Aug 23 30–60
Lima Beans — May 24 — Jul 26 – Sep 6 60–90
Mache Mar 29 May 3 May 10 Jun 21 – Jul 26 40–60
Microgreens Mar 29 May 3 May 10 May 17 – Jun 14 7–21
Mizuna Mar 29 May 3 May 10 Jun 14 – Jul 12 30–45
Mustard Greens Mar 29 May 3 May 10 Jun 14 – Aug 16 30–50
Napa Cabbage Mar 29 May 3 May 10 Jul 5 – Aug 9 55–75
Onion Mar 29 May 3 May 10 Aug 9 – Sep 13 90–120
Pac Choi Mar 29 May 3 May 10 Jun 21 – Jul 19 40–55
Parsnip — May 3 — Aug 16 – Sep 6 100–130
Patty Pan Squash Mar 29 May 24 May 31 Jul 19 – Aug 16 45–60
Peas Mar 29 May 3 May 10 Jul 5 – Aug 30 55–70
Peppers Feb 22 May 24 May 31 Aug 2 – Oct 4 60–90
Pole Beans Mar 8 May 24 May 31 Jul 26 – Sep 20 55–70
Potatoes Mar 8 May 24 May 31 Aug 9 – Oct 4 70–120
Pumpkin Mar 29 May 24 May 31 Aug 30 – Oct 4 85–120
Purslane Mar 29 May 3 May 10 Jun 21 – Jul 26 40–60
Radish — May 3 — May 31 – Jun 21 22–35
Rhubarb — — Jun 7 — 365–730
Romanesco Mar 29 May 3 May 10 Jul 26 – Sep 6 75–100
Rutabaga — May 3 — Jul 26 – Aug 30 80–100
Salsify — May 3 — Aug 16 – Sep 6 100–130
Savoy Cabbage Mar 29 May 3 May 10 Jul 19 – Sep 13 70–110
Scallions Mar 29 May 3 May 10 Jul 5 – Aug 2 50–70
Scarlet Runner Beans Mar 8 May 24 May 31 Aug 2 – Sep 6 60–80
Shiso Mar 15 May 17 May 31 Jul 26 – Sep 20 50–70
Snap Peas Mar 8 May 24 May 31 Jul 26 – Sep 20 55–70
Snow Peas Mar 29 May 3 May 10 Jul 5 – Aug 30 50–65
Soybeans — May 24 — Aug 16 – Sep 27 80–120
Spaghetti Squash Mar 29 May 24 May 31 Aug 30 – Sep 27 85–100
Spinach Mar 29 May 3 May 10 Jun 14 – Aug 16 35–50
Squash (Summer) Mar 29 May 24 May 31 Jul 19 – Sep 20 45–65
Squash (Winter) Mar 29 May 24 May 31 Aug 23 – Oct 4 80–120
Sunchoke — — May 24 Sep 13 – Sep 27 110–150
Sweet Corn — May 24 — Jul 26 – Sep 6 60–90
Tatsoi Mar 29 May 3 May 10 Jun 14 – Jul 19 35–50
Tomatoes Mar 8 May 24 May 31 Aug 2 – Oct 4 60–85
Turnip — May 3 — Jun 14 – Jul 19 40–60
Watercress Mar 29 May 3 May 10 Jun 21 – Jul 26 40–60
Wax Beans — May 24 — Jul 19 – Sep 13 50–65
Zucchini Mar 29 May 24 May 31 Jul 19 – Sep 13 45–60

Fruits for Zone 3b

Plant Start Indoors Direct Sow Transplant Harvest Days to Maturity
Alpine Strawberries — — Jun 7 Sep 6 – Oct 11 90–180
Aronia — — Jun 7 — 730–1095
Blueberries — — Jun 7 — 730–1095
Cranberries — — Jun 7 — 730–1095
Currants — — Jun 7 — 730–1095
Elderberries — — Jun 7 — 730–1095
Goji Berries — — Jun 7 — 730–1095
Gooseberries — — Jun 7 — 730–1095
Hardy Kiwi — — Jun 7 — 1095–1825
Haskaps — — Jun 7 — 730–1095
Jostaberry — — Jun 7 — 730–1095
Lingonberries — — Jun 7 — 730–1095
Raspberries — — Jun 7 — 365–730
Serviceberries — — Jun 7 — 730–1095
Strawberries — — Jun 7 Sep 6 – Oct 11 90–365

Herbs for Zone 3b

Plant Start Indoors Direct Sow Transplant Harvest Days to Maturity
Angelica Mar 29 May 3 May 3 — 365–730
Bee Balm — — May 17 Aug 16 – Sep 20 90–120
Borage Mar 29 May 3 May 3 Jun 28 – Aug 16 50–60
Caraway Mar 29 May 3 May 3 — 365–450
Catnip — — May 17 Jul 19 – Sep 20 60–80
Chamomile Mar 29 May 3 May 3 Jul 5 – Sep 6 60–90
Chervil Mar 29 May 3 May 3 Jun 14 – Aug 16 40–60
Chives — — May 17 Jul 19 – Sep 20 60–90
Cilantro Mar 29 May 3 May 3 Jun 14 – Aug 16 40–60
Comfrey — — May 17 Jul 19 – Sep 20 60–90
Dill Mar 29 May 3 May 3 Jun 14 – Aug 16 40–60
Garlic Chives — — May 17 Jul 19 – Sep 20 60–90
Horehound — — May 17 Aug 2 – Sep 20 75–90
Hyssop — — May 17 Jul 26 – Sep 20 70–90
Lemon Balm — — May 17 Jul 19 – Sep 6 60–70
Lovage — — May 17 Jul 26 – Sep 20 70–90
Mint — — May 17 Jul 19 – Sep 20 60–90
Parsley Mar 29 May 3 May 3 Jul 5 – Sep 6 60–80
Sorrel Mar 29 May 3 May 3 Jun 14 – Aug 16 40–60
Valerian — — May 17 Sep 20 120–180

Flowers for Zone 3b

Plant Start Indoors Direct Sow Transplant Harvest Days to Maturity
Ageratum Mar 15 May 24 May 24 Jul 19 – Sep 20 60–75
Alliums — — — Sep 22 – Oct 20 28–42
Astilbe Mar 1 — May 24 Aug 16 – Oct 4 70–100
Bachelor's Button Mar 15 May 3 May 10 Jul 12 – Sep 6 60–90
Begonias Feb 22 — May 24 Aug 2 – Sep 27 70–90
Black-eyed Susan Mar 1 May 10 May 24 Aug 16 – Oct 18 60–80
Bleeding Hearts Mar 1 — May 24 Jul 19 – Aug 30 60–90
Calendula Mar 22 May 3 May 10 Jun 28 – Sep 6 50–70
Celosia Mar 29 May 31 May 31 Aug 2 – Oct 11 60–90
Columbine Mar 1 May 24 May 24 Jul 19 – Aug 30 70–100
Coreopsis Mar 1 May 17 May 24 Aug 16 – Oct 18 60–80
Cosmos Apr 12 May 17 May 17 Jul 26 – Oct 4 60–90
Crocus — — — Jun 9 – Jul 7 10–20
Daffodils — — — Jun 16 – Jul 14 20–40
Dahlias Apr 12 May 24 May 24 Aug 30 – Oct 18 70–120
Daylily Mar 1 — May 24 Aug 30 – Oct 18 60–90
Dianthus Mar 1 Apr 26 May 10 Jun 28 – Aug 23 60–80
Echinacea (Purple Coneflower) Mar 1 May 24 May 24 Aug 23 – Oct 18 70–90
Foxglove Mar 1 May 24 May 24 Jul 19 – Aug 30 80–120
Gaillardia (Blanket Flower) Mar 15 May 24 May 24 Aug 2 – Oct 25 70–100
Geraniums Feb 22 — May 24 Aug 2 – Sep 27 70–100
Gladiolus — May 24 May 24 Aug 30 – Oct 18 70–100
Hostas Feb 15 — May 24 Aug 30 – Oct 18 60–90
Hyacinths — — — Jul 7 – Jul 28 14–28
Hydrangeas Feb 15 — May 24 Aug 16 – Oct 4 90–150
Impatiens Mar 8 — May 24 Aug 9 – Sep 27 60–75
Irises — — May 24 Jul 19 – Aug 16 60–100
Larkspur — Apr 5 — Jun 14 – Jul 26 60–90
Lilies — — May 24 Aug 16 – Oct 11 70–120
Lobelia Mar 1 — May 17 Jul 12 – Aug 30 70–80
Lupine Mar 1 May 24 May 24 Jul 19 – Aug 30 75–100
Marigolds Mar 29 May 24 May 24 Jul 19 – Sep 27 50–70
Nasturtium Apr 12 May 24 May 24 Jul 19 – Sep 27 55–65
Pansy Feb 15 — May 10 Jul 5 – Aug 16 70–90
Peonies — — May 24 Aug 2 – Aug 30 90–120
Petunia Mar 8 — May 24 Aug 9 – Oct 4 70–90
Phlox Mar 1 May 24 May 24 Aug 16 – Oct 11 80–110
Portulaca Mar 29 May 31 May 31 Jul 19 – Sep 20 50–70
Roses Feb 15 — May 24 Aug 16 – Oct 18 90–180
Salvia Mar 1 — May 24 Aug 2 – Sep 27 70–90
Sedum (Stonecrop) Mar 1 — May 24 Sep 27 – Nov 8 60–90
Snapdragon Feb 22 — May 10 Jul 19 – Sep 6 70–100
Sunflower Apr 19 May 24 May 24 Aug 16 – Oct 11 70–100
Sweet Alyssum Mar 15 May 10 May 10 Jun 21 – Aug 16 45–60
Sweet Pea Mar 22 Apr 12 May 10 Aug 2 – Sep 13 65–85
Tulips — — — Jun 30 – Jul 21 15–30
Vinca (Annual) Feb 22 — May 24 Aug 2 – Sep 27 70–90
Yarrow Mar 1 May 10 May 24 Aug 16 – Oct 18 60–90
Zinnia Apr 12 May 24 May 24 Aug 2 – Oct 4 60–70

Recommended for Your Garden

💡
LED Grow Lights $25-60

Full-spectrum LED lights for starting seeds indoors when daylight is limited.

Recommended for cold-climate zones (1-4).

🔥
Seedling Heat Mat $15-35

Warm soil for faster germination of heat-loving crops like tomatoes and peppers.

Recommended for cold-climate zones (1-4).

🪡
Floating Row Covers $12-30

Protect plants from frost, wind, and pests while letting light and water through.

Recommended for cold-climate zones (1-4).

Frequently Asked Questions

What can I grow in Zone 3b?

Zone 3b supports 170 plants in our database including vegetables, herbs, fruits, and flowers. With a 135-day growing season (last frost ~May 10, first frost ~September 22), you can grow most common garden crops with proper timing.

What is Zone 3b?

USDA Zone 3b has an average annual minimum temperature of -35°F to -30°F.

When is the last frost in Zone 3b?

The average last spring frost in Zone 3b is approximately May 10. The first fall frost averages around September 22, giving a growing season of about 135 days. These dates are based on 50% probability — plan for some year-to-year variation.

Composting Guide for Homesteaders

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
Start composting today →

Monthly Planting Guide for Zone 3b

Other Zones

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals, University Cooperative Extension planting guides. Planting dates are estimates based on average frost dates — local conditions may vary. Last updated: July 2026.

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Sources & credits

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

Plant varieties + growing data

Soil survey + temperature data

Drought monitoring

Household-consumption benchmarks

Derived

Other

Frost dates

Modeling

Precipitation + climate normals

Curated

Pest + disease pressure

Local extension offices

Daylight hours + sun data

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