When to Plant Kale: Your Comprehensive Kale Planting and Care Guide

Posted in: Other Vegetables
When to Plant Kale: Your Comprehensive Kale Planting and Care Guide

Whether you love smoothies, salads or sautés, kale is a must-grow in any home garden. A relative of broccoli and cabbage, you can grow a bumper crop of kale in mere weeks. If you're asking yourself questions like when to plant kale and how far apart to plant kale, we're here to help. Here's everything you need to know about growing kale for a lush, leafy harvest.

When Should You Plant Kale?

Kale is considered a cool season crop, which means it performs best in spring and fall in most parts of the country. If you're wondering when to plant kale in your hardiness zone, base your planting dates around your first and last frost dates. For northern states, plant kale seeds and seedlings outdoors in early spring — roughly three to five weeks before your average last frost date. Remove plants when they start to go to seed (also known as bolting) when summer temps set in. Then, begin growing kale again six to eight weeks before your anticipated first frost date for a fall crop. If you live in a southern or coastal climate with mild winters, you can grow kale from late fall through the winter.

How Far Apart Do You Plant Kale?

On average, plant kale 18 inches apart in rows 2 feet apart. However, you should always defer to your variety's seed packet or plant tag for spacing instructions. For example, 'Lacinato' kale needs 2 to 3 feet of space, while 'Red Russian' kale spreads only a foot wide. If you're planting seeds, you can always plant them closer together, then thin your rows to your variety's recommended spacing once seedlings emerge.

How Deep Should You Plant Kale?

Always let your seed packet be your guide, but in general, plant kale seeds 1/4 to 1/2 inches deep. For garden-ready plants, dig a hole twice as wide as the root ball and carefully place the plant at the same depth as its current container. Carefully cover with the surrounding soil.

Can You Start Kale Seeds Indoors?

You can either direct-sow kale seeds or start them indoors six to eight weeks before your last and first frost dates. Make seed-starting easy with a reusable tray filled with soil pellets, and place them under a sunny windowsill or grow light. Once seedlings have sprouted, harden them off by putting them outdoors in the morning for a couple of hours, then work your way up to leaving them outside around the clock over several days.

What Are the Ideal Growing Conditions for Kale?

Temperature

Kale grows its most vigorous (and delicious) below 75 degrees Fahrenheit and can even handle temperature dips below 25 F. In fact, many gardeners think kale tastes better after a light frost. However, it turns bitter and tough in the dog days of summer.

Sunlight

For maximum growth, plant kale in full sun, where it will receive six to eight hours of direct sunlight per day. However, it's possible to grow kale successfully in partial sun, with just four to six hours of sunlight. In other words, full sun is best, but don't sweat it if your kale encounters a little shade.

Soil

Plant kale in fertile, well-drained soil. Test your soil and aim for a pH of 6.0 to 7.5. If you need to change your soil's pH, your test results will advise what to do. Before planting, work compost into topsoil for an instant nutrient boost.

Water

Kale needs 1 to 1.5 inches of water each week. Keep the soil damp but not waterlogged. Opt for one to two deep waterings per week versus a daily spritz — less frequent waterings encourage roots to grow deeper and more robust.

Fertilizer

Kale benefits from a nitrogen boost once plants reach several inches tall. Apply a nitrogen-rich fertilizer, such as Burpee's Natural Organic Blood Meal 12-0-0, according to package directions.

Location

Grow versatile kale in a wide variety of areas. While you can opt for traditional in-ground or raised-bed vegetable gardens, kale adds a unique texture to large containers and adds an element of surprise when tucked in among ornamentals.

What Kind of Kale Should You Grow?

While you may remember it as the rabbit food-like garnish from the restaurants of your childhood, kale comes in a variety of colors, sizes and textures to please every palate. Here are a few fun picks to fuel your greens-growing obsession:

  • 'Red Winter Organic': Sweeter and easier to chew than many varieties, think of this as entry-level kale.

  • 'Prizm Hybrid': Whether you're after soups, sautés or kale chips, 'Prizm' features leaves strong enough for any use.

  • Kale Blend: Can't decide? Grow three top-performing varieties from the same seed packet.

When Do You Harvest Kale?

Harvest kale any time after the plant has eight or more leaves. Simply trim or snap at the base, starting with the outermost leaves.

FAQs About Growing Kale

Is kale easy to grow?

Yes, gardeners widely consider kale easy to grow.

How long does it take kale to grow?

You can grow kale from seed to harvest in six to eight weeks, depending on your growing environment.

How long do kale plants last?

Kale is technically a biennial, meaning it lives for two growing seasons. However, you should swap out plants after a spring harvest and again at the end of the growing season to maintain optimal flavor and texture.

Learn more about common kale pests and problems in Burpee's kale encyclopedia.

Written by Kelly Reilly, www.kelly-reilly.com

Kelly's passion is empowering new gardeners to achieve their goals through accessible, easy-to-understand digital content.

June 29, 2022
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