SproutGuide Almanac · updated weekly

SproutGuide

What to plant this week in Zone 4b

Week of 2026-W31

Zone 4b gardeners are now well into the growing season, with an average last frost date of May 12 and first frost expected around October 1. This week offers a busy harvest window for crops like sweet corn, zucchini, cherry tomatoes, basil, and bush beans that were planted earlier in the spring.

The next 7 days

Sample: Duluth, MN
Today
7/28
75° 58°
Wed
7/29
86° 61°
Thu
7/30
86° 66° 💧33%
Fri
7/31
80° 65° 💧65%
Sat
8/1
72° 58° 💧12%
Sun
8/2
76° 56°
Mon
8/3
90° 59° 💧13%
Avg high 80°F Rain total 0.4" Humidity 74% Wind 5.7 mph
In the ground

Sow this week

No direct sowing windows open this week.

Move out

Transplant this week

Nothing is due to go out this week.

Coming ripe

Harvest soon

46 crops
  • Bachelor's Button (Cornflower)
  • Basil
  • Beet
  • Bell Pepper
  • Borage
  • Bush Bean
  • Cabbage
  • Carrot
  • Cauliflower
  • Cherry Tomato
  • Cleome (Spider Flower)
  • Collard Greens
  • Cosmos
  • Cowpea (Black-Eyed Pea)
  • Cucumber
  • Dill
  • Fava (Broad) Bean
  • Fennel
  • French Marigold
  • Garlic
  • German Chamomile
  • Ground Cherry
  • Kale
  • Napa Cabbage
  • Nasturtium
  • Onion
  • Ornamental Sweet Potato Vine
  • Pansy
  • Parsley
  • Pole Bean
  • Potato
  • Rutabaga
  • Scallion (Bunching Onion)
  • Scarlet Runner Bean
  • Shallot
  • Shishito Pepper
  • Snapdragon
  • Summer Savory
  • Sweet Corn
  • Swiss Chard
  • Thai Basil
  • Tomato
  • Vinca (Madagascar Periwinkle)
  • Yellow Summer Squash
  • Zinnia
  • Zucchini
Do this now

Seasonal tips

  • Succession sow snap beans or Swiss chard every two weeks to ensure a continuous harvest through summer.
  • Mulch around newly transplanted peppers and tomatoes with straw to retain soil moisture and keep roots cool as temperatures rise.
  • Thin out carrot tops gently if they are overcrowded to allow the remaining plants to bulge up nicely for harvest.
  • Stake tall crops like sweet corn, pole beans, and indeterminate tomato varieties now before heavy winds arrive.
Keep watch

Pest & disease watch

  • Watch for aphids on new growth of basil, cosmos, and zinnias; a strong spray of water often suffices.
  • Inspect the undersides of cabbage leaves for flea beetles which can cause small 'shot-hole' damage.
  • Check cucumber and squash plants for early signs of powdery mildew during this humid period.
Water

Watering this week

Water deeply at soil level in the morning to prevent fungal issues while ensuring thirsty crops like corn and beans get consistent moisture.

One more thing

Pull weeds carefully around your garlic and onion beds now, as they are storing energy for bulb development before winter.

All year

Zone 4b planting calendar

140 crops

Average planting and harvest windows for everything that grows in zone 4b — dates shift a week or two with the season, so treat them as a starting point and check the weekly guide above for what's open right now.

Vegetables 66

CropStart indoorsSow outdoors TransplantHarvestMaturity JanFebMarAprMayJunJulAugSepOctNovDec
Anaheim (New Mexico) Pepper Mar 17 – Mar 31 — May 26 – Jun 9 Aug 9 – Aug 28 78d
Artichoke Mar 17 – Mar 31 — May 12 – May 26 — 165d
Arugula — Apr 14 – May 26 — May 14 – Jul 5 35d
Asparagus — — Apr 14 – May 12 — 2.5 yr
Banana Pepper Mar 17 – Mar 31 — May 26 – Jun 9 Jul 30 – Aug 28 73d
Beefsteak Tomato Mar 31 – Apr 14 — May 19 – Jun 2 Aug 7 – Sep 5 88d
Beet — Apr 14 – Jun 9 — Jun 3 – Aug 18 60d
Bell Pepper Mar 17 – Mar 31 — May 26 – Jun 9 Jul 25 – Sep 7 75d
Bok Choy — Apr 28 – May 26 — Jun 7 – Jul 15 45d
Broccoli Mar 24 – Apr 7 — Apr 28 – May 12 Jun 22 – Jul 21 63d
Brussels Sprouts Mar 31 – Apr 14 — May 12 – May 26 Aug 10 – Sep 13 100d
Bush Bean — May 19 – Jul 19 — Jul 8 – Sep 17 55d
Cabbage Mar 17 – Mar 31 — Apr 28 – May 12 Jul 7 – Aug 10 80d
Carrot — Apr 21 – Jun 9 — Jun 20 – Aug 28 70d
Cauliflower Mar 24 – Apr 7 — May 12 – May 26 Jul 6 – Aug 9 65d
Cayenne Pepper Mar 17 – Mar 31 — May 26 – Jun 9 Aug 4 – Aug 28 75d
Celery Mar 3 – Mar 17 — May 12 – May 26 Aug 20 – Oct 3 115d
Cherry Tomato Mar 31 – Apr 14 — May 19 – Jun 2 Jul 13 – Aug 11 63d
Collard Greens — Apr 28 – May 26 May 12 – May 26 Jun 22 – Aug 9 65d
Cowpea (Black-Eyed Pea) — May 26 – Jul 7 — Jul 25 – Oct 5 75d
Cucumber — May 26 – Jul 14 May 26 – Jun 9 Jul 15 – Sep 17 58d
Edamame — May 26 – Jun 23 — Aug 9 – Sep 21 83d
Eggplant Mar 17 – Mar 31 — May 26 – Jun 9 Jul 30 – Sep 2 75d
Fava (Broad) Bean — Mar 31 – Apr 28 — Jun 9 – Aug 6 85d
Flour Corn — May 19 – Jun 23 — Aug 17 – Oct 21 105d
Garden Pea — Mar 31 – Apr 28 — May 25 – Jul 7 63d
Garlic — Sep 3 – Oct 15 — May 1 – Oct 22 255d
Ghost Pepper (Bhut Jolokia) Mar 3 – Mar 17 — May 26 – Jun 9 Sep 3 – Oct 7 110d
Gourd (Ornamental/Bottle) — May 26 – Jun 9 — Sep 3 – Oct 7 110d
Habanero Pepper Mar 17 – Mar 31 — May 26 – Jun 9 Aug 24 – Sep 17 95d
Jalapeño Mar 17 – Mar 31 — May 26 – Jun 9 Jul 30 – Sep 2 75d
Kale Mar 31 – Apr 14 Apr 28 – May 26 Apr 28 – May 12 Jun 17 – Jul 30 58d
Kohlrabi — Apr 14 – May 12 — May 24 – Jul 6 48d
Leek Mar 3 – Mar 17 — May 12 – May 26 Aug 20 – Sep 23 110d
Lettuce Mar 31 – Apr 14 Apr 14 – May 26 Apr 28 – May 12 May 29 – Jul 25 53d
Lima Bean — May 26 – Jul 7 — Jul 30 – Oct 5 78d
Loofah (Luffa) — May 26 – Jun 23 May 26 – Jun 9 Aug 24 – Oct 22 120d
Marconi Pepper Mar 17 – Mar 31 — May 26 – Jun 9 Aug 9 – Sep 2 80d
Mustard Greens — Apr 14 – May 26 — May 19 – Jul 10 40d
Napa Cabbage Mar 17 – Mar 31 — Apr 28 – May 12 Jun 17 – Jul 31 65d
Onion Mar 3 – Mar 17 — Apr 14 – Apr 28 Jul 13 – Aug 16 100d
Parsnip — Apr 28 – May 26 — Aug 6 – Sep 23 110d
Poblano Pepper Mar 17 – Mar 31 — May 26 – Jun 9 Jul 30 – Aug 28 73d
Pole Bean — May 19 – Jul 9 — Jul 18 – Sep 17 65d
Potato — Apr 28 – May 26 — Jul 7 – Sep 23 95d
Pumpkin — May 26 – Jun 9 — Aug 29 – Oct 7 108d
Radish — Apr 14 – Jun 9 — May 6 – Jul 9 26d
Rhubarb — — Apr 14 – May 12 — 1.5 yr
Roma Tomato Mar 31 – Apr 14 — May 19 – Jun 2 Jul 28 – Aug 21 75d
Rutabaga — Apr 28 – May 26 — Jul 27 – Sep 3 95d
Scallion (Bunching Onion) — Apr 14 – Jun 9 — Jun 13 – Aug 18 65d
Scarlet Runner Bean — May 19 – Jul 9 — Jul 18 – Sep 17 65d
Serrano Pepper Mar 17 – Mar 31 — May 26 – Jun 9 Aug 9 – Aug 28 78d
Shallot — — Apr 14 – Apr 28 Jul 13 – Aug 6 95d
Shishito Pepper Mar 17 – Mar 31 — May 26 – Jun 9 Jul 20 – Aug 13 60d
Snow Pea — Mar 31 – Apr 28 — May 30 – Jul 7 65d
Spinach — Mar 31 – May 12 — May 5 – Jun 26 40d
Sugar Snap Pea — Mar 31 – Apr 28 — May 25 – Jul 2 60d
Sweet Corn — May 19 – Jun 23 — Jul 23 – Sep 21 78d
Swiss Chard — Apr 28 – Jun 9 — Jun 17 – Aug 8 55d
Tomatillo Mar 31 – Apr 14 — May 19 – Jun 2 Aug 2 – Sep 10 88d
Tomato Mar 31 – Apr 14 — May 19 – Jun 2 Jul 18 – Aug 26 73d
Turnip — Apr 14 – May 26 — May 24 – Jul 25 50d
Winter Squash — May 26 – Jun 9 — Aug 24 – Sep 27 100d
Yellow Summer Squash Apr 21 – Apr 28 May 26 – Jul 24 May 26 – Jun 9 Jul 10 – Sep 17 50d
Zucchini Apr 21 – Apr 28 May 26 – Jul 24 May 26 – Jun 9 Jul 10 – Sep 17 50d

Herbs 19

CropStart indoorsSow outdoors TransplantHarvestMaturity JanFebMarAprMayJunJulAugSepOctNovDec
Anise Hyssop — — May 12 – Jun 9 — 1.5 yr
Basil Mar 31 – Apr 14 May 26 – Jul 9 May 26 – Jun 9 Jul 15 – Sep 17 60d
Chervil — Apr 28 – May 26 — Jun 12 – Jul 25 53d
Chives — Apr 14 – May 12 Apr 28 – May 26 — 75d
Cilantro — Apr 28 – May 26 — Jun 7 – Jul 20 48d
Dill — Apr 28 – Jun 9 — Jun 7 – Aug 3 48d
Fennel — May 12 – Jun 19 — Jul 16 – Sep 17 78d
French Tarragon — — May 12 – Jun 9 — 85d
German Chamomile — Apr 28 – May 26 — Jun 27 – Jul 30 63d
Ginger — — Jun 9 – Jul 7 — 270d
Lemon Balm — — May 12 – Jun 9 — 80d
Lemongrass — — May 12 – Jun 9 — 105d
Mint — — May 12 – Jun 9 — 75d
Oregano — — May 12 – Jun 9 — 85d
Parsley Mar 3 – Mar 17 — Apr 28 – May 26 Jul 7 – Aug 24 80d
Sage — — May 12 – Jun 9 — 83d
Shiso (Japanese Basil) Mar 31 – Apr 14 May 19 – Jun 24 May 19 – Jun 2 Jul 28 – Sep 17 78d
Summer Savory Mar 31 – Apr 14 May 26 – Jul 9 May 26 – Jun 9 Jul 25 – Sep 17 65d
Thai Basil Mar 31 – Apr 14 May 26 – Jul 4 May 26 – Jun 9 Jul 25 – Sep 17 68d

Fruits 19

CropStart indoorsSow outdoors TransplantHarvestMaturity JanFebMarAprMayJunJulAugSepOctNovDec
Apple — — Apr 14 – May 26 — 3.5 yr
Black Walnut — — Apr 28 – Jun 9 — 4.5 yr
Blackberry — — Apr 14 – May 12 — 1.2 yr
Blueberry — — Apr 28 – Jun 9 — 2.5 yr
Cantaloupe Apr 21 – Apr 28 May 26 – Jun 19 May 26 – Jun 9 Aug 4 – Sep 17 80d
Cranberry — — Apr 28 – Jun 9 — 1.5 yr
Elderberry — — Apr 28 – Jun 9 — 2.5 yr
Gooseberry — — Apr 28 – Jun 9 — 2.5 yr
Grape — — Apr 28 – May 26 — 2.5 yr
Ground Cherry Mar 31 – Apr 14 — May 19 – Jun 2 Jul 23 – Aug 16 70d
Honeyberry (Haskap) — — Apr 28 – Jun 9 — 2.5 yr
Honeydew Melon Apr 21 – Apr 28 May 26 – Jun 9 May 26 – Jun 9 Aug 14 – Sep 17 90d
Pear — — Apr 14 – May 26 — 3.5 yr
Plum — — Apr 14 – May 26 — 3.5 yr
Raspberry — — Apr 14 – May 12 — 1.2 yr
Red/Black Currant — — Apr 28 – Jun 9 — 2.5 yr
Strawberry — — Apr 14 – May 12 — 243d
Tart (Pie) Cherry — — Apr 14 – May 26 — 3.5 yr
Watermelon Apr 21 – Apr 28 May 26 – Jun 14 May 26 – Jun 9 Aug 9 – Sep 17 85d

Flowers 36

CropStart indoorsSow outdoors TransplantHarvestMaturity JanFebMarAprMayJunJulAugSepOctNovDec
Bachelor's Button (Cornflower) — Apr 14 – May 26 — Jun 18 – Aug 4 68d
Bee Balm — — May 12 – Jun 9 — 1.5 yr
Black-Eyed Susan — May 12 – Jun 9 May 12 – Jun 9 — 110d
Borage — May 12 – Jul 9 — Jul 6 – Sep 17 63d
Butterfly Milkweed — — May 12 – Jun 9 — 1.5 yr
Calendula — Apr 28 – May 26 — Jun 12 – Jul 25 53d
Cleome (Spider Flower) — May 19 – Jul 4 — Jul 13 – Sep 17 65d
Cosmos — May 19 – Jun 19 — Jul 18 – Sep 17 75d
Dahlia — — May 19 – Jun 2 Aug 17 – Sep 30 105d
Delphinium — — May 12 – Jun 9 — 1.5 yr
French Marigold Apr 7 – Apr 21 May 19 – Jul 19 May 19 – Jun 2 Jul 3 – Sep 17 53d
Garden Geranium (Zonal) Mar 3 – Mar 17 — May 19 – Jun 2 Jul 28 – Aug 31 80d
Garden Phlox — — May 12 – Jun 9 — 1.5 yr
Garden Rose (Shrub) — — May 12 – Jun 9 — 1.5 yr
Garden Verbena Mar 17 – Mar 31 May 19 – Jun 19 May 19 – Jun 2 Jul 28 – Sep 17 80d
Hardy Hibiscus — — May 12 – Jun 9 — 1.5 yr
Hearts & Flowers (Heartleaf Iceplant) — — May 19 – Jun 9 — 75d
Hollyhock Mar 17 – Mar 31 — Apr 28 – May 12 — 1.5 yr
Lantana Mar 17 – Mar 31 — May 19 – Jun 2 Jul 28 – Aug 31 80d
Lisianthus (Prairie Gentian) Feb 17 – Mar 3 — May 26 – Jun 9 Sep 3 – Oct 7 110d
Nasturtium — May 19 – Jul 14 — Jul 8 – Sep 17 58d
New England Aster — — May 12 – Jun 9 — 1.5 yr
Oriental Poppy — — May 12 – Jun 9 — 1.5 yr
Ornamental Sweet Potato Vine — — May 26 – Jun 23 Jul 25 – Sep 21 75d
Panicle Hydrangea — — Apr 28 – Jun 9 — 2.5 yr
Pansy Mar 3 – Mar 17 — Apr 14 – Apr 28 Jun 23 – Jul 27 80d
Petunia Mar 3 – Mar 17 — May 19 – Jun 2 Jul 28 – Aug 31 80d
Purple Coneflower — — May 12 – Jun 9 — 1.5 yr
Salvia — — May 19 – Jun 2 — 110d
Sedum ('Autumn Joy'-type) — — May 12 – Jun 9 — 1.5 yr
Snapdragon Mar 17 – Mar 31 — Apr 28 – May 12 Jul 17 – Aug 20 90d
Sunflower — May 19 – Jun 23 — Jul 28 – Oct 1 85d
Sweet Alyssum — Apr 28 – May 26 May 12 – May 26 Jun 17 – Jul 25 55d
Vinca (Madagascar Periwinkle) Apr 14 – Apr 28 May 19 – Jul 4 May 19 – Jun 2 Jul 18 – Sep 17 68d
Yarrow — — May 12 – Jun 9 — 135d
Zinnia Apr 14 – Apr 28 May 19 – Jul 4 May 19 – Jun 2 Jul 18 – Sep 17 68d
Local pages

Cities in zone 4b

4

Duluth, MN · Helena, MT · Great Falls, MT · Quebec City, QC

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