Kale is a hardy leafy green belonging to the Brassica oleracea species, related to cabbage, broccoli, and Brussels sprouts. Unlike its relatives, kale does not form a compact head, instead producing a rosette of elongated, edible leaves. It is generally considered one of the easiest and most forgiving vegetables for home gardeners to cultivate, offering a long growing season.
Is Kale Truly Easy to Grow
Kale is genuinely resilient and simple to grow because it tolerates a wider range of conditions than many other garden crops. Its most notable trait is extreme cold hardiness, allowing it to withstand temperatures as low as -15°C (5°F) and continue producing into winter. This tolerance means it can be planted early in spring and late in summer, effectively extending the harvest period.
The plant is also less demanding regarding soil quality compared to other vegetables, and it quickly germinates from seed. However, this hardiness should not be mistaken for a complete lack of challenges. The primary obstacle for gardeners is intense pressure from specific pests attracted to this family of greens. Despite this common pest issue, kale is exceptionally forgiving of minor neglect and varied weather, making it a reliable crop for beginners.
Optimal Conditions for Planting and Growth
For robust growth and tender leaves, kale thrives best in full sun, though it will still produce a harvest in partial shade. The ideal soil is fertile and well-draining, amended with aged compost or other rich organic matter before planting. A slightly acidic to neutral soil pH, ideally between 6.5 and 6.8, promotes fast growth and deters certain diseases.
Kale is a cool-season crop, performing best when air temperatures do not consistently exceed 24°C (75°F). Gardeners can start seeds indoors four to six weeks before the last expected spring frost, or direct-seed into the garden as soon as the soil is workable. For a continuous harvest, succession planting involves sowing new seeds every few weeks throughout the cooler parts of the growing season.
Planting a second round in late summer, approximately 75 days before the first fall frost, ensures a substantial autumn and winter yield. Consistent moisture is important for leaf quality, requiring about 2.5 to 4 centimeters (1 to 1.5 inches) of water per week. Applying an organic mulch layer, such as straw or shredded leaves, helps maintain even soil moisture and keeps the roots cool.
Protecting Kale from Pests and Disease
The primary challenge in growing kale is managing the pests that target all members of the Brassica family. The cabbage worm, the larva of the Cabbage White butterfly, is a common culprit that chews large, ragged holes in the leaves. Another frequent pest is the flea beetle, which creates numerous small, shotgun-like holes, especially on young seedlings.
One of the most effective non-chemical methods for prevention is using physical exclusion barriers like fine mesh row covers. These covers are placed over the plants immediately after transplanting and prevent adult insects from laying eggs on the leaves. For an active infestation of caterpillars, an organic bacterial spray containing Bacillus thuringiensis (Bt) can be applied. This spray is toxic to the larvae but safe for beneficial insects and humans.
Disease issues are less frequent but can occur, such as leaf spot or clubroot, a soil-borne fungus. Proper spacing of plants, typically 30 to 60 centimeters (12 to 24 inches) apart, ensures good air circulation. This is a simple way to prevent the spread of fungal diseases. Crop rotation, where kale is not planted in the same spot for several years, minimizes the buildup of soil-borne pathogens.
Maximizing Your Kale Harvest
To ensure the kale plant continues to produce leaves for months, gardeners should employ the “cut-and-come-again” harvesting method. This technique involves picking only the mature, outer leaves from the bottom of the plant. It is important to leave the central growing point and at least four to six inner leaves intact so the plant can continue photosynthesizing and generating new growth.
The flavor of kale improves after the plant has been exposed to a light frost, which triggers the conversion of starches into sugars, resulting in a sweeter taste. Harvested leaves can be stored by washing and then wrapping loosely in a damp paper towel before placing them in a plastic bag in the refrigerator. This simple storage method helps the greens maintain crispness and freshness for up to a week.