Learning how to grow kale is simple. This cool-season veggies is a staple in my winter garden. I plant kale in the fall and it keeps producing until temperatures warm in the spring. Each kale plant typically yields dozens and dozens of tasty leaves. Keep reading for 5 tips for growing kale including how to grow kale in Arizona.
According to The Vegetable Gardener’s Bible, kale is “almost perfect. Kale has just about everything – good looks, good flavor, and high vitamin and mineral content. Plus it’s super-hardy and rarely bothered by bugs. Kale is like a really good friend – there for you when everything else in the garden (and in life) has failed you. It’s easy to grow, healthful and hardy enough to harvest from under the snow.” I love author Edward C. Smith’s enthusiasm for growing kale!
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5 Tips for How to Grow Kale
1. How to grow kale: Understand temperature requirements for kale
Kale (Brassica oleracea) prefers cool weather, and a frost improves kale’s flavor. Kale can be grown in the heat but will become tough and bitter.
Begin planting kale 3-4 weeks before last spring frost date, and again in midsummer for a fall harvest. Plant kale in the fall and winter in hot summer areas.
When to plant kale in the low desert of Arizona:
- Start seeds indoors: August – December
- Plant seeds outside: September 15 – December
- Plant transplants outside: September 15 – January
Succession planting of kale ensures a steady harvest through spring and into summer.
As the weather warms, kale will become bitter and send up a flower stalk; this means the kale is bolting and has switched its focus to production of seeds
2. How to grow kale: Give kale room to grow
Each kale plant requires enough space to allow sunlight to reach the leaves and grow well.
Plant kale seeds ½ inch deep about 3 inches apart; when plants are about 5 inches tall, thin the plants to 12 inches apart. (Thinned kale seedlings are tender and delicious – be sure to eat them!) Rows of kale should be spaced about 18 inches apart.
When square foot gardening, allow one kale per square foot.
When planting kale transplants, plant kale up to the first leaves, burying the stem.
3. How to grow kale: Plant different varieties
Growing several varieties of kale adds variety to your garden and makes the most of this versatile vegetable.
Lacinato kale, also called dinosaur kale or Tuscan kale. This Italian kale may date back to the 18th century. The leaves have a savoy cabbage texture and are best eaten when leaves are small and tender. Plants can become quite tall on central stalk as leaves are harvested. Order seeds from Botanical Interests here.
Curly kale – one of the most common types is Siberian but there are several varieties. The finely-curled leaves of curly kale have a bright peppery flavor that is improved by frost. Plants grow about 18 inches tall. Order seeds from Renee’s Garden here.
Red Russian kale grows 2-3 feet tall with large oak-like purplish leaves. The flavor and color are enhanced by frost. Order seeds from Botanical Interests here.
4. How to grow kale: Grow kale organically
Kale is the easiest member of the the brassica family (which includes broccoli, cauliflower, Brussels sprouts, and more) to grow. Kale is less prone to pests and disease than many of its cousins. Follow these guidelines to easily grow kale organically:
- Plant kale in compost-rich soil, and mulch with more compost throughout the growing season.
- Water evenly. Having healthy plants is the best way to prevent pests.
- Pick off weathered or damaged leaves. Clean up debris around plants.
- Pick caterpillars by hand off lacinato kale; they are easy to spot, just look for the holes in the leaves. You can also use Bt to control caterpillars.
- Spray aphid infestations on kale with water or with a little dish soap mixed with water. Be sure to rinse off afterwards.
- Consider using floating row covers to prevent caterpillars and other pests.
- Practice companion planting to prevent pests. Nasturtiums and onions are both excellent companions for kale.
5. How to grow Kale: Harvest kale correctly
Kale leaves grow from a central stem that gets longer as the kale grows. Smaller leaves have a milder flavor and more tender texture than larger leaves.
- Harvest individual leaves when they are about the size of your hand.
- Harvest kale leaves from the bottom of the plant first, snapping or cutting off each leaf at the stem to avoid damaging the terminal bud (found at the top center of the plant). The plant will continue to produce leaves on the inner stem from the terminal bud.
- When the plant’s production slows or you wish to harvest the entire plant, cut the main stem at soil level allowing roots to break down and decompose in the soil.
Kale is best eaten fresh from the garden, but can be stored in the refrigerator in storage containers for up to 2 weeks. Kale freezes well. Rinse and store in a freezer container. Once frozen, the kale can be crumbled and added to soups and smoothies.
Make a green powder “superfood” with extra leaves from brassicas after harvesting. Learn how in this blog post.