Best Time to Plant Kale in Massachusetts: Key Dates and Tips

Best Planting Times for Kale in Massachusetts

Planting Method	Activity	Recommended Dates
Outdoor Planting	Indoor Seed Starting	March 1 – April 1
	Transplant Outdoors	April 15 – May 15
Fall Planting	Direct Sow Outdoors	August 1 – September 1

Planting Conditions

Massachusetts has a humid continental climate with cold winters and warm summers, falling within USDA Hardiness Zones 5a to 7a. These conditions are ideal for cool-season crops like kale, particularly in the spring and fall.

Plant kale outdoors approximately 4-6 weeks before the last frost in spring, and 6-8 weeks before the first frost in fall.

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Useful Tools for Starting Kale Indoors

Using the right tools can save you time and increase your success rate.

Seeds

Quality seeds lead to better germination and healthier plants. Starting with high-quality seeds gives your kale the best chance to thrive from the very beginning.

Browse Kale Seeds on Amazon

Planting Trays

Planting trays help you organize your seedlings and ensure they have enough space to grow before you transplant them outdoors. This makes the process more efficient and increases the chances of strong, healthy plants.

Find Planting Trays on Amazon

Grow Lights

Grow lights are essential if you don’t have enough natural sunlight. They provide your seedlings with the light they need to grow strong and healthy, even in less-than-ideal conditions.

Check out Grow Lights on Amazon

Seed Starting Soil

Using light, fine soil specifically designed for seed starting helps young roots establish quickly and promotes healthy growth. It’s an easy way to give your seedlings the best start possible.

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Garden Tools and Fertilizer

Garden Trowel

A garden trowel is a handy tool that makes transplanting your seedlings easier and more precise, ensuring that each plant is placed at the right depth without damaging the roots.

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Soil and Fertilizer

Fertilizer is essential for enhancing growth, especially if your soil is nutrient-poor. By enriching the soil, you give your kale plants the nutrients they need to grow robust and produce a bountiful harvest.

Explore Fertilizer on Amazon

Other planting guides for Michigan:

Any questions on growing kale? Visit our forum to discuss: Growing Kale

Average Last Frost Dates for Massachusetts’s Largest Cities

City	Average Last Frost Date
Boston	April 20
Worcester	April 25
Springfield	April 28
Lowell	April 26
Cambridge	April 21
New Bedford	April 22
Brockton	April 23
Quincy	April 21
Lynn	April 22
Fall River	April 24

Average First Frost Dates for Massachusetts’s Largest Cities

City	Average First Frost Date
Boston	October 25
Worcester	October 15
Springfield	October 10
Lowell	October 15
Cambridge	October 20
New Bedford	October 25
Brockton	October 20
Quincy	October 22
Lynn	October 23
Fall River	October 24

Please note: These dates are averages and can vary from year to year. It’s always a good idea to monitor local weather forecasts and consider your specific location and microclimate when planning your gardening activities.

Starting Kale Indoors

In areas like Boston (Zone 6b), start kale seeds indoors from March 1 to April 1. This timing ensures that seedlings are ready for outdoor transplanting from mid-April to mid-May, after the last frost.

Transplanting Kale Seedlings

Transplant seedlings outdoors from April 15 to May 15, ensuring soil temperatures are consistently above 45°F. Space seedlings 12-18 inches apart in rows at least 18 inches apart to allow for good air circulation and sunlight exposure.

General Care and Maintenance

Watering:

Water deeply and consistently to keep the soil evenly moist. Massachusetts’s warm summers can dry out the soil quickly, so regular watering is essential.
Water at the base of the plants to prevent wetting the foliage, which helps reduce the risk of fungal diseases.

Fertilizing:

Apply a balanced fertilizer at planting and again when the leaves begin to develop. Adding compost to the soil before planting can improve fertility and soil structure.

Pest and Disease Management:

Monitor for common pests like aphids, flea beetles, and cabbage worms. The humid climate can also encourage fungal diseases, so vigilance is necessary.
Use organic or integrated pest management strategies to protect your plants from pests and diseases.

Harvesting Kale:

Harvest kale leaves when they are large enough to eat but still tender. Regular harvesting encourages new growth and extends the harvesting season, particularly in Massachusetts’s cooler fall climate.