May is the month when cold climate gardens come alive. In northern regions across Canada, Scandinavia, northern Europe, and the northern United States, May is often the first time the soil is warm enough to plant in earnest, and the pace of the growing season suddenly picks up.

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By May, cool-tolerant vegetables can go directly into the ground, and the seedlings you started indoors in April are ready to begin hardening off for transplanting. It is a busy and rewarding month.

This guide explains which vegetables to plant in May, which crops should still be started indoors, and how to take advantage of the short growing season.

Quick Answer: What to Plant in May in a Cold Climate

If you are gardening in a cold or northern climate, May is one of the most active planting months. As soil temperatures rise and daylight hours increase, many vegetables can be planted directly outdoors.

Vegetables you can plant in May include:

• carrots
• beets
• lettuce
• spinach
• radishes
• peas
• green onions
• kale

These crops tolerate cool spring conditions and grow steadily as temperatures gradually warm.

If you missed the April window, peas can still go in early May – just check that soil temperature is at least 7°C (45°F). Growing Peas in Cold Climates – complete guide →

Many of these vegetables are also ideal for succession planting, allowing gardeners to harvest continuously throughout the early growing season.

For a full seasonal overview, see our Cold Climate Planting Calendar.

May Planting Checklist for Cold Climate Gardens

Use this checklist to take advantage of the main spring planting window.

• Sow root crops such as carrots and beets

• Continue planting leafy greens like lettuce and spinach

• Plant peas and other cool-season crops

• Start succession planting every one to two weeks for continuous harvests

• Thin seedlings early to give plants room to grow

• Maintain consistent watering as temperatures begin to rise

May is one of the most productive months for planting in cold climate gardens.

Why May Planting Works in Cold Climate Gardens

May feels warmer, but it demands respect. Frost is still possible in most cold climate regions, sometimes well into the second half of the month. The smart approach is to plant frost-hardy crops directly and hold off on frost-sensitive ones until conditions are reliable.

Typical May conditions include:

• gradually warming soil
• cool nights
• increasing daylight

These conditions are ideal for cool-season vegetables and many fast-growing crops.

Starting the right vegetables in May helps establish strong plants before the warmer part of the summer arrives.

Vegetables You Can Plant in May

May opens up more planting options than any other month in cold climate gardens. Most cool-season crops can go directly in the ground, and the longer days help them establish quickly.

What you can plant in May include:

• spinach
• lettuce
• peas
• radishes
• carrots
• beets
• turnips

These crops tolerate cool temperatures and germinate well in slightly warmer spring soil.

Leafy greens are especially productive during this period because they grow quickly before summer heat arrives.

Learn more about these crops in our guide to leafy greens in a cold climate garden.

Fast Growing Vegetables for May Planting

May is an excellent time to plant fast growing vegetables.

These crops mature quickly and are ideal for regions with short summers.

Examples include:

• radish
• arugula
• spinach
• lettuce
• turnips

Many of these vegetables are ready to harvest in just a few weeks.

You can explore more quick crops in our guide to fast growing crops for cold climate gardening.

Transplanting Seedlings in May

May is often the time when seedlings started indoors can begin moving into the garden.

Common transplants include:

• cabbage
• kale
• onions
• broccoli

Before transplanting, it is important to harden off seedlings by gradually exposing them to outdoor conditions. How to Harden Off Seedlings in Cold Climates – complete 14-day guide →

If you are starting plants indoors, see our guide to seed starting in cold climates.

May is transplanting time for tomatoes in Zone 4–5 and H6–H7 – but only once soil has reached at least 15°C (60°F) and nights are reliably above 10°C. Full guide: Growing Tomatoes in Cold Climates →

Preparing the Garden for Rapid Growth

As temperatures increase in May, plant growth accelerates.

To support healthy plants:

• maintain soil moisture
• add compost if needed
• keep garden beds weed-free

Healthy soil structure helps vegetables grow faster and produce better harvests.

You can learn more about soil preparation in our article on soil preparation for cold climate gardening.

Protecting Plants from Late Frost

Although May brings warmer weather, late frost is still possible in many cold climates.

Gardeners often protect plants using:

• row covers
• cold frames
• low tunnels

These simple tools allow crops to continue growing even when temperatures drop unexpectedly.

For more information, see our guide to season extension for cold climate gardening.

Quick May Planting Checklist

In May you can:

plant cool-season vegetables
transplant hardy seedlings
plant fast growing crops
protect plants from late frost

May is one of the most productive planting months of the year in cold climates. Every crop you get in the ground now is a harvest you will enjoy through the summer.

Continue Planning Your Garden

By the end of May, the garden is filling up. June brings warmer soil, longer days, and the chance to plant a wider range of crops, including some that cannot go in until frost risk has fully passed.

If you are building a full planting schedule, these guides will help you plan the rest of the season:

• What to Plant in April
• What to Plant in June
• What to Plant in July
• What to Plant in August
• What to Plan in September

You can also explore our full cold climate planting calendar for a month-by-month overview of what to plant throughout the growing season.