How to Grow Kale

Kale is a versatile and nutrient-packed leafy green that thrives in various climates and garden settings.

With its hardy nature and ability to grow year-round in many regions, kale offers a steady supply of fresh, flavorful leaves for a range of dishes. Understanding its growing requirements and care techniques helps the gardener enjoy abundant kale harvests.

Published: November 21, 2024.

Choosing the Right Kale Variety

Kale comes in several varieties, each offering unique flavors, textures, and growth characteristics.

Curly kale, the most common type, has bright green, frilly leaves and a slightly peppery taste that mellows when cooked. It is highly versatile and grows well in various conditions.

Lacinato kale, also known as dinosaur or Tuscan kale, has dark green, textured leaves and a sweet, nutty flavor. This variety is particularly prized for its ability to hold its shape in cooking, making it ideal for soups and stews.

Red Russian kale, with its tender, flat leaves tinged with purple veins, is known for its sweeter taste and suitability for salads and light cooking.

Choosing the right variety depends on your culinary preferences, garden space, and climate.

For colder regions, Red Russian kale is a hardy option, while Lacinato kale thrives in slightly warmer conditions. Mixing varieties in your garden can also provide diversity in both flavor and appearance.

Ideal Soil and Climate Conditions for Kale

Kale thrives in well-draining soil with a slightly acidic to neutral pH range of 6.0 to 7.5. Enrich the soil with organic matter such as compost or aged manure to support the plant's nutrient needs.

Kale is a heavy feeder, requiring adequate levels of nitrogen for lush leaf growth. Consider adding a balanced fertilizer or blood meal to provide a steady supply of nutrients.

This cool-season crop grows best in temperatures between 55°F and 75°F (13°C to 24°C) but can tolerate light frosts, which often enhance its flavor.

Avoid planting during extreme heat, as it can cause the leaves to become bitter. If you live in a warmer region, consider planting kale in partial shade or during the cooler months.

Preparing Your Garden for Planting Kale

Before planting kale, prepare your garden by clearing weeds and loosening the soil to a depth of at least 12 inches. Incorporate a layer of compost or well-rotted manure to improve soil fertility and structure. If your soil is particularly heavy, consider adding sand or perlite to enhance drainage.

Test the soil pH and adjust it if needed by adding lime to raise pH or sulfur to lower it. To further boost nutrient availability, mix in an organic fertilizer rich in nitrogen. Creating raised beds or rows can help ensure good drainage, especially in areas prone to heavy rainfall.

For an extra layer of protection against pests, consider using row covers after planting. These covers also help retain warmth, promoting faster seed germination and early growth. Preparing the garden thoughtfully sets the stage for healthy and productive kale plants.

Starting Kale: Seeds vs. Transplants

When starting kale, you have two primary options: growing from seeds or using transplants.

Growing from seeds offers the advantage of lower costs and a broader selection of varieties. Seeds can be directly sown into the garden soil or started indoors about 4-6 weeks before the last frost date to give the plants a head start. Direct sowing is ideal if you live in a region with a long growing season, while starting indoors allows for an earlier harvest in cooler climates.

Transplants, on the other hand, are convenient for gardeners who want to skip the germination process or have a shorter growing window. While slightly more expensive than seeds, transplants reduce the time to harvest and offer a reliable option for beginners or those with limited gardening experience.

Choose seeds if you want full control over the growing process and enjoy experimenting with varieties. Opt for transplants when time is limited or you want an easier start to your kale-growing journey.

Planting Kale: Spacing and Depth Guidelines

Proper spacing and planting depth are critical for healthy kale growth. If planting seeds directly into the soil, sow them about 1/4 to 1/2 inch (0.6 to 1.2 cm) deep, with rows spaced approximately 12 to 18 inches (30 to 45 cm) apart.

Once seedlings emerge, thin them to maintain a spacing of 8 to 12 inches (20 to 30 cm) between plants. This ensures each plant has enough room for air circulation and growth.

For transplants, dig a hole slightly larger than the root ball and position the plant so that the base of the stem is level with the soil surface. Space the transplants 12 to 18 inches (30 to 45 cm) apart in rows. If you are planting multiple rows, leave at least 18 inches (45 cm) between rows to facilitate airflow and ease of maintenance.

Crowding kale can lead to issues like reduced yield and increased susceptibility to diseases, so take care to follow these spacing guidelines for optimal results.

Watering and Fertilizing Kale for Maximum Yield

Kale requires consistent moisture to thrive, especially during its early growth stages. Aim to provide 1 to 1.5 inches (2.5 to 3.8 cm) of water per week, either through rainfall or supplemental irrigation.

Deep watering once or twice a week is more effective than shallow, frequent watering, as it encourages the roots to grow deeper into the soil. Mulching around the base of the plants helps retain moisture, regulate soil temperature, and suppress weeds.

Fertilizing kale is essential for sustained leaf production. Incorporate a nitrogen-rich fertilizer, such as fish emulsion or blood meal, every 4-6 weeks.

Alternatively, side-dress the plants with compost or a balanced organic fertilizer mid-season to replenish nutrients. Avoid over-fertilizing, as it can lead to overly lush growth and reduced flavor.

Monitoring soil moisture and nutrient levels ensures kale remains vibrant and productive throughout the growing season. Consistency in watering and feeding will reward you with tender, flavorful leaves.

Companion Planting: Best Partners for Kale

Companion planting is an effective way to enhance kale's growth and protect it from pests. Some plants act as natural repellents, while others improve soil health or attract beneficial insects.

Alliums such as garlic, onions, and chives help deter pests like aphids and cabbage worms with their strong scent. Marigolds are another excellent companion, as they repel nematodes and attract predatory insects that feed on kale pests.

Legumes like beans and peas contribute nitrogen to the soil, enriching the nutrient content for kale’s growth. Planting herbs such as dill, cilantro, or rosemary nearby can confuse pests with their fragrance while inviting pollinators to the garden.

Avoid planting kale near crops in the Brassica family (e.g., broccoli, cauliflower, or cabbage) to minimize competition for nutrients and reduce the risk of shared pests or diseases.

Thoughtful companion planting not only protects your kale but also fosters a healthier and more diverse garden ecosystem.

Managing Pests and Diseases in Kale

Kale is susceptible to a variety of pests and diseases, but proactive management can keep these issues under control.

Aphids, small sap-sucking insects, often cluster on the undersides of leaves. They can be removed with a strong spray of water or by introducing natural predators like ladybugs.

Cabbage worms, the larvae of moths and butterflies, chew holes in kale leaves. Hand-picking them or applying organic insecticides such as Bacillus thuringiensis (Bt) can effectively manage infestations.

Powdery mildew, a fungal disease that appears as white, powdery spots on the leaves, thrives in humid conditions. Improve air circulation by spacing plants correctly and avoiding overhead watering. For prevention and treatment, use a fungicidal spray made from neem oil or a mixture of baking soda and water.

Regularly inspect your kale for early signs of trouble, and remove any damaged or infected leaves to prevent the spread of diseases. Healthy plants are naturally more resilient, so maintaining optimal growing conditions is key.

Harvesting Kale: Timing and Techniques

Kale leaves are best harvested when they are tender and full of flavor. Begin harvesting once the leaves are about 6 to 8 inches (15 to 20 cm) long, typically 55 to 75 days after planting. Start with the outer leaves, cutting them close to the base of the stem while leaving the central growth point intact.

This approach, known as "cut-and-come-again," encourages the plant to continue producing new leaves throughout the season.

If a full harvest is desired, cut the entire plant at the soil level. This is often done at the end of the growing season or if the kale begins to bolt (flower).

For the sweetest flavor, harvest kale in the morning after a cool night or wait until after a light frost, as cold temperatures enhance its natural sugars.

Store freshly harvested kale in a cool, humid environment, such as the crisper drawer of your refrigerator. Proper harvesting techniques ensure a continuous supply of delicious, nutrient-rich leaves for weeks or even months.

Storing and Using Freshly Harvested Kale

To maintain the freshness of harvested kale, avoid washing it before storage, as excess moisture can lead to spoilage. Instead, gently shake off any dirt and remove damaged leaves. Store kale in a perforated plastic bag or a breathable container in the refrigerator's crisper drawer.

It can stay fresh for up to 1 week when kept at a temperature around 32°F (0°C) with high humidity. If you need longer storage, blanch the kale for 2-3 minutes, then freeze it in airtight containers or freezer bags for up to 12 months.

Fresh kale is incredibly versatile in the kitchen. It can be used raw in salads and smoothies, sautéed as a side dish, or added to soups and stews for a nutritional boost.

Kale chips, made by baking lightly oiled and seasoned leaves, are a healthy snack option. Its rich flavor and robust texture make it an excellent addition to a variety of meals.

Growing Kale in Containers or Small Spaces

Kale is an excellent choice for container gardening, as it thrives even in limited spaces. Choose a container that is at least 12 inches (30 cm) deep with adequate drainage holes to prevent waterlogging.

Use a high-quality potting mix enriched with organic compost to provide essential nutrients. Position the container in a location that receives 6-8 hours of sunlight daily, or use grow lights if natural light is insufficient.

Plant kale seeds or transplants with the same spacing guidelines as in-ground gardening, leaving 8-12 inches (20-30 cm) between plants. Regularly check soil moisture, as containers dry out faster than garden beds. Fertilize every few weeks with a liquid organic fertilizer to support continuous growth.

Kale grown in containers can be easily moved to optimize sunlight exposure or shield it from harsh weather, making it an ideal solution for urban gardens or patios.

Extending Kale’s Growing Season

With the right techniques, you can enjoy fresh kale nearly year-round. In colder climates, use row covers or frost blankets to protect plants from light frosts while maintaining a stable growing environment. Cold frames or hoop houses provide additional insulation, allowing kale to thrive even during winter months.

Planting frost-tolerant varieties like Red Russian or Siberian kale further extends the growing season, as these types can withstand temperatures as low as 20°F (-6°C). For extremely cold regions, growing kale indoors under grow lights is a viable option.

In warmer climates, extend the growing season into the summer by providing partial shade and mulching to keep the soil cool. By planning ahead and using these techniques, you can ensure a continuous harvest of kale regardless of the season.

Ornamental Kale: Beauty and Functionality in the Garden

Ornamental kale is a stunning addition to gardens and landscapes, known for its vibrant, frilly leaves that come in shades of purple, pink, white, and green.

Unlike traditional kale varieties grown for consumption, ornamental kale is cultivated primarily for its aesthetic appeal. Its ability to withstand cooler temperatures makes it a favorite for fall and winter displays, often used in flower beds, borders, or container arrangements to add texture and color.

Though ornamental kale is grown for its visual beauty, it is technically edible. The leaves are safe to eat, just like other varieties of kale. However, ornamental kale is not typically grown with taste in mind. Its leaves are tougher, more bitter, and less flavorful than culinary kale varieties. While it won’t harm you to consume ornamental kale, it’s best used as a garnish or in cooked dishes where its texture and bitterness can be softened.

In addition to its role in beautifying gardens, ornamental kale is low-maintenance and thrives in well-drained soil with plenty of sunlight. It can tolerate frost, making it an excellent choice for extending garden interest into colder months.

Whether used for its striking appearance or sparingly in the kitchen, ornamental kale adds versatility and charm to any outdoor space.