It wasn’t long ago that I had not heard of kale. Kale has grown in popularity due to its exceptional nutrient value, health benefits and flavor. I am fond of eating kale because it holds its texture even when cooked. For me, texture is one of the most important characteristics when eating vegetables. I like incorporating kale into pasta and soup recipes, one of which I have included below. This blog post will focus on how to successfully grow kale in your garden.
Kale has interesting varieties, including ornamental varieties. Here is a summary of the different varieties of kale:
- Curly Leaf (Darkibor, Westlander)
- Bumpy Leaf (Lacinato, Dinosaur)
- Plain Leaf (Red Russian, White Russian)
- Leaf and spear (a cross between curly and plain leaf)
- Ornamental (tougher leaves, grown for decoration)
A few interesting facts about kale:
- In 2012, kale salad at Brooklyn restaurant, Battersby, was named dish of the year by Bon Appétit
- Kale has its roots in Greek and Roman culture
- Before its rise to fame, kale was commonly used as a decorative garnish by restaurants
Kale is popular now, but people have been growing this super food for more than 2,000 years.
WebMD
SUCCESSFULLY GROW AND CARE FOR KALE
Kale is considered a cool season crop and therefore is one of the first crops that can be planted in the spring and can also be planted for a fall harvest. Young kale can withstand temperatures down to 25°F. Mature kale can withstand even colder temperatures. I can remember a gardener sharing a picture of his kale covered in snow.
In the spring, soil temperature should reach a minimum of 40°F before direct seeding or setting out transplants. For a fall planting, direct seed or set out transplants 6-8 weeks before the first fall frost. In both spring and fall, I use a fabric row cover to protect my transplants from cold and pests.
Kale plants can be grown from transplants or direct seeded in the ground. The soil needs to reach a temperature of 40°F before sowing seeds or setting out transplants. Transplants should have 4-6 true leaves and a well-developed root system before transplanting. It will take 5-6 weeks to grow transplants of this size. For more information on starting plants from seeds, read my blog titled “The complete guide to starting seeds indoors”. Kale also does well direct seeded if the temperature does not exceed 75°F. Here are the general guidelines to successfully grow kale:
Grow Kale
- Kale prefers a soil that is fertile, well-drained and amended with organic matter (e.g. the addition of compost and/or manures). Compost can be made at home or purchased from a garden center. For information on making compost at home, reference my blog titled “Recipes for Compost”. It is best to work compost into the soil in the fall for a spring planting. Kale prefers a soil pH of 6.0 to 7.5. T o understand your soil pH and nutrient levels, it is advised to get your soil tested.
- For soil fertility, apply a seaweed/fish emulsion fertilizer (with an NPK of 2-3-1) to the soil prior to transplanting or seeding and then again, every two to three weeks. NPK stands for N-Nitrogen, P-Phosphorus, K-Potassium. The three numbers (2-3-1) represent the percentage of each nutrient in a complete fertilizer.
- Kale transplants can be planted 4-5 weeks before the last frost date in your area. This is also the time to direct seed kale. For a fall planting, direct seed or set out transplants 6-8 weeks before the first anticipated fall frost. Kale will continue growing through the winter but needs a good start.
- Follow the guidelines on the back of the seed package for planting depth and spacing. If you are interested in intensive offset planting, then the recommended spacing for kale is 12 inches. This planting method is part of the ‘intensive organic planting’ method and increases, by approximately 10%, what can be planted in a given area. I follow this method of planting and have had good success.
Care for Kale
- Kale required 1-2 inches of water per week. It is best to water deeply and infrequently, keeping and even soil moisture.
- Organic mulches (e. g. straw, dry shredded leaves) can be used to ensure that the ground retains moisture and maintains the soil temperature. Plastic mulches can also be used to maintain soil temperatures, reduce weeds, maintain moisture and allow earlier planting. A row cover can be used to protect the crop from cold and insects.
- Fertilize by side dressing (apply to the ground around the plant) the kale once after transplanting with an organic nitrogen fertilizer such as Blood Meal. Place the fertilizer 6 inches to the side of the plant and water well.
- Companion crops include strawberries, tomatoes and pole beans
Kale going to seed
Below are two common insect problems with kale. When considering chemical controls or if you are unsure of the pest or disease, check with your Cooperative Extension for help in identifying and determining appropriate controls.
- Cabbage worms and loopers – worms are light to dark green. The loopers are yellow-green caterpillars. The worm adult is a white butterfly that lays eggs on the underside of leaves. These worms chew holes in leaves and hide in the center of the head. Options for control include:
- Manually removing the eggs
- Use sticky traps to catch the adult butterfly
- Aphids – tiny green or black insects that feed on the underside of leaves ultimately causing the leaf to die and fall off. Insecticidal soaps or a strong water stream from a hose can be used to dislodge.
Kale can be harvested 50-75 days after it is planted (depending upon the variety). Kale can either be harvested whole or can be continuously harvested by picking off the outermost leaves. I enjoy picking off the leaves because this allows me to pick just what is needed. New leaves will grow in to replace what was picked. Harvest early in the morning before the heat of the day begins. After harvesting, separate the leaves and clean in a bath of cold water, dry with dish or paper towels, place in a plastic bag and store in the refrigerator. Kale w ill keep 1-2 weeks if stored dry and at a refrigerated temperature of 32°F.
The stems on kale can be thick and tough. For large leaf kale, gently pull off the leaves on both sides of the stem . Kale can be eaten cold in a salad or can be cooked by blanching, microwaving, sautéing or steaming. Kale is low in calories, high in nutrients including vitamin A, C, K and B6, and is a good source of iron, fiber, potassium and calcium.
Here is my favorite kale recipe. Kale is also a great addition to soup and can be eaten as a salad.
- Curly Leaf: Westlander Kale (50 days to maturity) This variety is cold tolerant with large flavorful leaves reaching 14-20 inches tall. It is suitable for both spring and fall planting.
- Curly Leaf: Darkibor F1 Kale (50 days to maturity) Dark green hybrid kale with leaves reaching 18-36 inches tall. It is suitable for both spring and fall planting.
- Plain Leaf: Red Russian Kale (21 days baby, 50 days full size) Bright purple stems and green, deeply lobed foliage. Grows 24-36 inches tall and is cold tolerant.
Family: Brassicaceae
Genus: Brassica
Species: (depends upon variety)
Montana State University Extension
Utah State University Cooperative Extension
North Carolina State University Extension
