Zone 3 Vegetable Planting Calendar: When to Sow and Transplant

When you buy through our links, we may earn a small commission at no additional cost to you. Learn more

Gardening in Hardiness Zone 3 can seem daunting due to the cold temperatures and shorter growing seasons. To help you navigate the challenges and capitalize on the opportunity, we’ve created the following Zone 3 Vegetable Planting Calendar.


The following table will give you an idea of when to sow seeds, either indoors or directly into the garden, and when to transplant them outdoors for optimal growth and yield.

What is Hardiness Zone 3?

The United States Department of Agriculture (USDA) Hardiness Zone Map categorizes geographical areas into zones based on their average annual minimum winter temperatures. Zone 3 is characterized by minimum temperatures ranging from -40°F to -30°F.

Planting Schedule for Zone 3

VegetableSow SeedsIndoors/OutdoorsTransplant Outdoors
Brussel SproutsFebruaryIndoorsApril
Collard GreensAprilOutdoorsN/A
Mustard GreensAprilOutdoorsN/A
Squash (Summer)MayIndoorsJune
Squash (Winter)MayIndoorsJune
Swiss ChardAprilOutdoorsN/A

(*) not recommended to be started from seed.
(**)not recommended for this hardiness zone.

Remember that these guidelines are general recommendations and can vary based on specific cultivars and local climate conditions. Always consider factors like the dates of your first and last frost, soil temperature, and daylight length when planning your garden.

Starting seeds indoors can extend the growing season, allowing for a greater range of vegetable types to be successfully grown in colder zones. It also provides a controlled environment that may result in stronger, healthier plants.

What States are in Zone 3?

  • Alaska
  • Minnesota
  • Montana
  • North Dakota
  • Wisconsin
  • Maine

Join Our Newsletter

Keep up to date on our latest articles

We’ll never send you spam or share your email address.
Find out more in our Privacy Policy.

Please note that only some portions of these states fall within Zone 3. Due to the localized nature of climate, it’s essential to consult the interactive USDA Hardiness Zone map to determine the specific hardiness zone for your given area.

Vegetable Gardening in Zone 3

While Hardiness Zone 3 can present a unique set of challenges due to its cold temperatures and shorter growing seasons, it’s still possible to enjoy a fruitful vegetable garden. With careful planning, soil preparation, and plant selection, and the use of our Zone 3 vegetable planting calendar, you can cultivate a range of delicious and nutritious vegetables right in your backyard.

Recommended Vegetables

Leafy Greens

Plants like kale, spinach, and collard greens not only tolerate cold but sometimes even become sweeter after a frost. These greens can be direct-sown in early spring or late summer for a fall crop.

Root Vegetables

Carrots, turnips, and beets are excellent choices for Zone 3. These root vegetables grow well in cooler soil and can be harvested late into the season.


Peas and beans can also be sown directly into the soil in late spring when the soil temperatures reach around 45°F. These crops can produce bountiful yields in the short growing season.

Indoor Sowing

Starting certain vegetables indoors can extend your growing season by several weeks. Plants like tomatoes, peppers, and eggplants need a long season to mature, so giving them a head start indoors is crucial.

Tips for Indoor Sowing:

Succession Planting

Succession planting involves sowing seeds at staggered intervals to ensure a continuous harvest throughout the growing season. This technique works well for quick-growing crops like radishes, arugula, and leaf lettuce.

Season Extension Techniques for Hardiness Zone 3: A Detailed Guide

Now that you’ve looked over our Zone 3 vegetable planting calendar, take a look at some ways you can extend your growing time. Season extension techniques can be a game-changer for gardeners in Hardiness Zone 3.

The colder climate and shorter growing seasons mean you have to make the most out of the available time.


What They Are:

Greenhouses are enclosed structures made of glass or plastic, providing a controlled environment for plants.


  • Consistent temperature
  • Humidity control
  • Protection from pests and strong winds

Best Practices:

  • Use thermal mass objects like water barrels to stabilize temperature.
  • Ensure proper ventilation to avoid mold and excessive humidity.

Cold Frames

What They Are:

Cold frames are a box-like structure with a transparent lid, often situated directly on the ground over your plants.


  • Easy and affordable to build
  • Can be used to harden off plants before transplanting
  • Provides a microclimate that is a few degrees warmer than outside

Best Practices:

  • Face the transparent lid towards the south for maximum light exposure.
  • Prop open the lid during the day to avoid overheating.

High Tunnels

What They Are:

High tunnels, also known as hoop houses, are taller than cold frames and usually made from a metal frame covered with plastic.


  • Walk-in access makes it easier for tending and harvesting
  • Can be used for a range of crops including taller plants like tomatoes
  • Generally easier to ventilate compared to smaller structures

Best Practices:

  • Install roll-up sides for better ventilation.
  • Use shade cloth during summer to reduce heat buildup.

Floating Row Covers

What They Are:

Row covers are lightweight blankets made of spun polyester or polypropylene placed directly over plants.


  • Lightweight and easy to install
  • Offers frost protection down to a few degrees
  • Allows water and light to reach the plants

Best Practices:

  • Use hoops or stakes to keep the material from directly touching sensitive plants.
  • Remove during the day if temperatures rise substantially.


What They Are:

Hotbeds are heated cold frames, often utilizing manure or electrical heating cables for warmth.


  • Provides a consistent heat source for seed germination
  • Ideal for plants that require higher soil temperatures

Best Practices:

  • Monitor temperature closely to avoid overheating.
  • Ensure adequate ventilation for humidity control.

Using one or more of these season extension techniques can significantly improve the range of plants you can grow and the duration of your growing season in Hardiness Zone 3. Whether you opt for a high-tech greenhouse or a simple cold frame, the goal is to create a more hospitable environment for your plants to thrive, despite the chillier conditions.

Tips for Successful Gardening in Zone 3

  1. Check Last Frost Dates: Always consult local frost dates before planting.
  2. Use Raised Beds: They warm up faster than ground soil, speeding up germination.
  3. Invest in Mulch: A layer of mulch helps retain soil moisture and temperature.

What Not to Grow

Certain plants like okra and artichoke are not suited for Zone 3 due to their high temperature and long growing season requirements.


Gardening in Hardiness Zone 3 is not about limitation; it’s about adaptation. By utilizing our Zone 3 vegetable planting calendar, understanding the unique climate and soil conditions, and by choosing plants wisely, you can cultivate a lush, productive garden.

So, put on those gardening gloves, and embrace the challenges of Zone 3!

FAQ: Zone 3 Vegetable Planting Calendar

About The Author

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Shopping Cart