How to Grow Organic Kale
What is Kale?
Kale is an incredibly healthful crop that can be easily grown in the backyard garden. It is very similar to the cabbage family, which includes broccoli, collard greens and cauliflower. It can be grown in almost any climate zone, and some areas (zone 6 or warmer) you can possibly overwinter planted kale for spring harvest.
Frosts can add a touch of sweetness to this green. But hot unprotected weather can turn it bitter and give it a tough texture
When to Plant Kale
When starting kale outside, you can plant seeds in very early spring as soon as the ground in your garden can be worked at all. Seeds in the process of germinating and new plants should be protected with row covers from heavy or otherwise killing frosts (under 25 degrees F) under floating row covers. Milder frosts are not a problem, in fact mild frosts give kale a sweeter flavor many people like.
For late season harvest, you can plant as late as six to eight weeks before expected first frost.
Where to Plant Kale
Kale prefers cooler temperatures and partial shade with about four hours of sun. In warm or dry climates, planting your organic kale in partial shade and with a layer of organic mulch will keep your garden soil a bit cooler. If you're expecting warm weather in your climate zone, full sun garden plots will give the plant that nasty tough and bitter experience that many people dislike about kale.
Kale can thrive in containers and raised beds if you ensure it is at least ten inches deep to give your plants' roots enough depth to get to the cool moisture below. Like the rest of the cabbage family, kale roots can grow exceptionally deep, so shallow gardening methods like Square Foot Gardening on hard surfaces are not ideal.
Some kale varieties will grow into handsome plants with deep greens and reds, so kale can be included in more decorative areas of your garden to add interesting yet edible accents to flower beds.
Kale seeds are planted half inch deep and 12 to 15 inches apart. Once your seeds have pushed through with their first leaves, give them a two to three inch layer of mulch to help with soil moisture.
Preparing the Soil for your Kale Garden
Like the rest of the cabbage family, kale can provide a great amount of nutrition and nutrients if the roots can access them. A good organic compost (preferably home-made with a wide variety of input waste) mixed into the soil will give you all the micronutrients possible. Kale prefers soil with a ph in the 6.0-7.0 range.
Kale Seeds and Germination
Kale seeds will germinate in cold as low as 45 degrees F, but will sprout in as little as a week in warmer temperatures like 70-75 degrees F.
Kale seeds will keep for as long as three to four years if stored appropriately.
Kale seeds will germinate in temperatures as low as 45ºF but germinate the quickest (5-10 days) in 70-75ºF.
Once you've purchased your kale seeds, they should last up to 4 years if stored in a cool, dry location.
Starting Kale Seeds Indoors
You can start seeds indoors four weeks before your expected last frost in the spring, and transplant to your outside garden right around expected last frost.
However, this method is more for your own benefit not working outside in the cold than for the plant itself. It does so well in cold weather that some overwintered plants have survived under mulch or covers down to below zero F.
You can also grow kale indoors, as described in the article about growing kale and lettuce inside during the winter.
Transplanting or Planting Kale Outside
Although kale will grow well in cooler weather, warming your growing area with black plastic covers will warm the soil closer to the ideal 70-75 degree level. Before summer heat arrives, apply mulch around plants to cool the roots. This will keep soil moisture from evaporating and reduce the chance your kale gets tough and bitter. Add fertilizer every 3 to 4 weeks, preferably in the form of an organic fish emulsion or compost tea from your compost heap.
How Much To Water Your Kale
Be sure your plants get at least one inch of water per week whether naturally (rain) or yourself (hose watering).
Kale Companion Plants / Rotation
Planting where other brassica family members such as cabbage, cauliflower and broccoli have grown in the last season should be avoided to reduce pests and disease.
Pests and Problems
The most common pest for kale is cabbage worm. These small green worms are the larvae of the Cabbage White butterfly, and will eat holes in the leaves of your kale as fast as you could in a salad. To control cabbage worms, pick them off by hand and squish them. You can also keep your kale covered with a floating row cover to eliminate the problem completely. Overhead watering will help detach insects from the plant.
Using compost or straw mulches will reduce the number of larvae hatched directly into the soil. It will also provide a habitat for ground and rove beetles, predators of the cabbage worm.
When to Harvest Kale
Plants mature in 50 to 65 days, depending on the variety. If you want kale for salads, you can pick some leaves much earlier – the smaller and more tender leaves taste great raw. As the growing kale plant develops, harvest the outside leaves and leave the plant. This is known as “cut and come again” harvesting which is very effective for smaller gardens to keep eating kale throughout the season. Some of the health benefits of kale depend on very quick 'pick to plate' times.
Storing Harvested kale
Kale can be kept in the refrigerator for as much as two weeks. Longer term storage for cooking is possible: chop, blanch and freeze the leaves for winter meals.
Eating Your Organic Kale / Recipes
Some good kale recipes are available on the internet. In my family we love kale chips, which are kale leaves lightly drizzled with oil and salt and baked until crispy. Kale can also be used for chicken and other livestock feed, especially those unfortunate plants that got too much sun in the summer or bolted.