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Planting CalendarSeed Starting Schedule

Zone 4a Planting Calendar 2026Complete Seed Starting Schedule

Zone 4a offers a growing season of about 135–145 days. With strategic indoor seed starting, gardeners can successfully grow a wide range of vegetables including tomatoes and peppers using short-season varieties. Covers parts of Minnesota, Wisconsin, Colorado, and the northern Midwest.

Cities: Minneapolis MN (suburbs), Green Bay WI, Madison WI (north), Boulder CO...

Last Frost

May 1

First Fall Frost

September 15

Growing Season

137 days

2026 Monthly Planting Schedule

Your month-by-month guide for Zone 4a

1January

🌱 Indoors: Start early crops indoors

☀️ Notes: Plan garden, order seeds

2February

🌱 Indoors: Start main season crops

🌍 Direct: Cold hardy crops direct sow

☀️ Notes: Prepare soil when workable

3March

🌱 Indoors: Continue seed starting

🌍 Direct: Direct sow cool season

☀️ Notes: Prepare beds

4April

🌱 Indoors: Finish warm season indoors

🌍 Direct: Direct sow beans, corn

☀️ Notes: Main transplant month

5May

🌍 Direct: Succession plant

☀️ Notes: Plant out all seedlings

6June

🌱 Indoors: Start fall crops

🌍 Direct: Plant fall vegetables

☀️ Notes: Maintain and water

7July

🌱 Indoors: Fall transplant seedlings

🌍 Direct: Plant fall crops

☀️ Notes: Begin fall planning

8August

🌍 Direct: Plant fall greens

☀️ Notes: Fall garden planting

9September

🌍 Direct: Plant garlic

☀️ Notes: Fall planting continues

10October

🌱 Indoors: Order seeds

☀️ Notes: Clean up, prepare winter

Recommended Varieties for Zone 4a

Top-performing varieties adapted to your zone

tomato

Better BoyEarly GirlCherokee PurpleBrandywine

pepper

California WonderJalapenoSweet BananaAnaheim

lettuce

ButtercrunchRomaineRed LeafSummertime

cucumber

Marketmore 76Straight EightBoston Pickling

squash

Yellow CrookneckBlack Beauty zucchiniButternut Waltham

Best Crops for Zone 4a

Top performers in your zone's climate

KaleCarrotBeetTomatoBush Bean

💡 Zone Tip: A hoop house or low tunnel can significantly extend your productive season. Start tomatoes 8 weeks before May 1 frost date.

Major Cities in Zone 4a

These areas share your hardiness zone

Minneapolis MN (suburbs)Green Bay WIMadison WI (north)Boulder COSpokane WA (east)Fargo ND

Zone 4a on the Map

Cities in your zone are highlighted. Click any marker to explore neighboring zone calendars.

Calculate Your 2026 Schedule

Neighboring Zones

Looking for a different zone?

Browse All 17 USDA Hardiness Zones →