Kale prefers moist, nutrient-rich soil, though it also grows well in moderately fertile soil. Work about 2 inches of compost into the garden bed, and add a high-quality organic fertilizer if needed.

Set your seedlings 12 to 18 inches apart for full-sized plants, or about 6 inches apart if you’ll be harvesting baby leaves from a cut-and-come-again patch. Water the seedlings thoroughly, and be sure to keep them watered as they grow. Although kale can be drought-tolerant, it will look and taste best if it is kept well hydrated.

If the lower leaves of your kale start to look yellow midseason, side-dress with alfalfa meal, soy meal, blood meal, or young compost. These amendments supply nitrogen, which kale needs in abundance to grow well.

3. Time planting and harvest to avoid heat stress

Kale is cold hardy and can be overwintered with some protection in USDA Hardiness Zones 5b and higher. Mulch with straw and top with a floating row cover to help your plants survive the coldest months of winter. When the plants wake up in early spring, they produce big, strong leaves, followed by delicious, edible flowers.

Westlander

This vigorous variety from Germany is uniquely aromatic and very hardy. Compact plants grow a bit larger than Dwarf Green Curled kale but remain a good choice for a smaller garden.

Red Russian 

You probably won’t see this variety at the farmers’ market; its tender leaves do not travel well. But harvested fresh from the garden, Red Russian’s sweet flavor, and tender texture are unparalleled. It keeps its mild sweetness throughout the season and maybe eaten cooked or raw.

Lacinato 

Also known as dinosaur kale or Nero di Toscana, this Italian heirloom has been around since the 18th century. Although it can be a slow grower, especially during the summer months, Lacinato stalks eventually grow up to 3 feet tall and often produce new leaves well into the winter months.

Dwarf Green Curled

This robust, frost-hardy variety only gets about 18 inches tall, making it a good choice for containers and raised beds. It is very cold hardy and insect resistant. Try it at the baby leaf stage to add loft and texture to salads.

Pests

Protecting kale plants

If flea beetles or caterpillars are a problem where you garden, it may be worthwhile to cover your kale crop with a floating row cover for the first month after it is set out in the garden.

Caterpillars also can be controlled with organic pesticides. Bt (Bacillus thuringiensis) is available as a spray or powder. Since it is most effective when caterpillars are small and actively feeding, it should be applied as soon as the pests appear. Spinosad (the active ingredient in Monterey Garden Spray and Captain Jack’s Deadbug Brew) also can be used for caterpillar control. Alternating between Spinosad and Bt can help keep pest populations from developing pesticide resistance, a problem made worse by the proliferation of genetically modified crops that produce Bt in their tissues. All pesticides should be applied in the early morning or evening to minimize exposure to nontarget species like butterflies.