Zone 3

USDA Hardiness Zone 3 covers regions with cold climates, experiencing average minimum winter temperatures between -40°F to -30°F (-40°C to -34°C). This zone includes areas in parts of Alaska, the northern United States, and southern Canada. Gardeners in Zone 3 face unique challenges such as short growing seasons and extreme cold, requiring them to select hardy plants that can withstand these conditions. Commonly grown plants include cold-tolerant trees like spruce and birch, shrubs like lilac and juniper, and perennials such as peonies and daylilies. Proper planning and the right plant choices are essential for a successful garden in this zone​.

What is the climate like in Zone 3?

Zone 3 experiences average minimum winter temperatures ranging from -40°F to -30°F (-40°C to -34°C). These frigid conditions require selecting plants that are exceptionally cold-hardy and capable of surviving prolonged periods of extreme cold.

The growing season in Zone 3 is relatively short, typically lasting around 100 to 120 days. This limited timeframe necessitates careful planning to ensure that plants have enough time to mature and produce a harvest before the first frost of fall​.

Frost can occur late into the spring and early in the fall, further narrowing the effective growing season. Gardeners must be mindful of the average last frost date in spring and the first frost date in fall to maximize their planting and harvesting schedules.

Heavy snowfall is common in Zone 3, which can benefit gardens by insulating the soil and protecting plant roots from extreme cold. However, the lingering snow can delay the start of the gardening season as the soil takes longer to thaw and become workable.

Freeze-thaw cycles can lead to soil heaving, which can damage plant roots. Proper soil management, including the use of mulch and organic matter, can help mitigate these effects. Additionally, ensuring good drainage is crucial to prevent waterlogging during the thaw periods.

What is the recommended planting schedule?

Below, you can see the recommended planting schedule for vegetables and herbs.


Plant Sow seeds indoor Transplanting to outdoor Harvesting Month Last date
Cucumber N/A N/A N/A N/A
Brussels Sprouts N/A N/A N/A N/A
Tomato N/A N/A N/A N/A
Spinach May 2 May 12 June 16 August 10
Beets May 9th May 19th July 8th July 13th
Zucchini N/A N/A N/A N/A
Cabbages N/A N/A N/A N/A
Potato May 10 May 20 July 19 July 3
Radish May 19 May 24 June 21 August 2
Broccoli May 8 May 18 July 12 July 8
Carrot May 12 May 26 August 18 June 15
Cauliflower May 13 May 20 July 9 July 16
Onion April 12 April 23 August 19 June 3


Plant Sow seeds indoor Transplanting to outdoor Harvesting Month Last date
Marjoram June 11 June 18 July 23 June 27
Parsley April 24 May 14 July 3 July 20
Dill N/A N/A N/A N/A
Fennel April 30 May 14 July 29 July 6
Sage N/A N/A N/A N/A
Thyme February 29 March 20 May 19 August 9
Oregano January 24 January 31 March 16 November 14
Mustard May 17 May 24 June 23 July 31
Mint N/A N/A N/A N/A
Lavender May 10 May 24 July 3 July 20
Rosemary April 27 May 12 July 31 June 26
Ginger N/A N/A N/A N/A
Basil N/A N/A N/A N/A
Cilantro N/A N/A N/A N/A