How to Plant, Grow, and Care For Collards in Your Garden
Collards are a staple vegetable for many families across the world. They have many uses, and are especially popular in the kitchen. But growing them can be a little tricky without the right information. In this article, organic gardening expert Logan Hailey walks through every step you'll need to follow in order to plant, grow, and care for collards.
Most commonly known as a southern classic, collard greens are an under-appreciated superfood cousin of kale. They are the perfect cool-weather crop for any region and can be cultivated throughout the winter in southern gardens.
Collards are most notable for the hardiness in the garden as well as the kitchen. These beginner-friendly crops can withstand drought, some heat, and frosty weather, and the sturdy leaves hold up to long cooking times in soups, stews, and braises.
If you’ve been looking for a new way to diversify your fall, winter, and spring greens selection, this delicious cabbage-cousin is fun and easy to grow. Collard greens are highly productive and eager to please in a variety of conditions. It’s one of those crops you can plant once and harvest for many months for a continuous supply of vitamin-rich leaves.
Due to widespread pesticide use on conventional leafy greens like collards, it is always safer and cheaper to grow organic collards in your own garden. With a few simple tricks, pretty much anyone can successfully grow these earthy-flavored greens and learn to use them in recipes. Let’s dig into how to plant, grow, and care for collard greens!
Plant Type Biennial, grown as Annual
Plant Family Brassicaceae
Plant Genus Brassica
Plant Species oleracea
Hardiness Zone USDA Zones 6-10
Planting Season Spring or late summer
Plant Maintenance Low
Plant Height Up to 30”
Fertility Needs Moderate
Temperature 50-75°F, can tolerate cold
Companion Plants Chamomile, Garlic, Onions
Soil Type Well-drained, fertile, pH 6.0-7.5
Plant Spacing 12-18” plants; 18-36” rows
Watering Needs Moderate, consistent
Sun Exposure Full sun
Days to Maturity 50-80 days
Pests Aphids, cabbage loopers
Diseases Black leg, black rot
History and Cultivation
Collards are one of the earliest cultivated vegetables, dating back to prehistoric times. The ancient Greeks grew a diversity of both collards and kale, typically making no distinction between them. Collards even pre-date their better-known cabbage relatives because the wild cabbage varieties were actually more like leafy collards.
Over time, gardeners and plant breeders developed types that curled into heads of leaves to create the modern cabbage types. Collards branched off on their own and have diversified into broad-leaf or slightly crinkled varieties.
The Romans grew many of these collard types and, along with the Celts, were likely responsible for taking the cole crops to England, Scotland, and France around the 4th century BC. Collard greens were used for centuries before they arrived in the United States, however they became most famously associated with southern style cooking amongst African slaves in pre-Civil War America.
What are Collards?
Collards are cabbage-family vegetables with large, smooth, waxy-textured leaves that are dark green or bluish-tinted. They can be grown in the summer, but their flavor and texture improves with frosts, making them a popular fall or winter crop in southern gardens.
Collards are members of the Brassicaceae or cole crop family, which also includes cabbage, kale, brussels sprouts, turnips, radishes, mustards, cauliflower, broccoli, and kohlrabi. The name “collard” actually comes from the word “colewort”, which was the medieval term for leafy brassica crops that didn’t form a head.
Wild Cabbage Origins
The common wild ancestor of all of these crops was likely wild cabbage (Brassica oleracea) growing on the Atlantic or Mediterranean coasts of southern and western Europe. The biennial or perennial plant formed a loose head of blue-green leaves with wavy edges or purple-tinted coloration and enjoyed the cool, moist coastal weather.
Today, collards and cabbages have diverged into separate lines entirely, but both are most commonly grown as annuals in the garden that are replanted every year.
Where Do Collards Originate?
Contrary to popular belief, collards originated in Europe and are not native to Africa. Their wild cabbage ancestors have mostly been found in the Mediterranean and Asia minor. However, the cooking traditions surrounding collards are most certainly of African origin.
These robust greens became a very important source of nutrition and flavor amongst African American slaves due to their hardy growth habit and wide availability on southern plantations.
Collard greens are easy to propagate and very similar to kale, cabbage, or other brassicas. They are most commonly grown from seed either directly sown in the garden in the late summer or transplanted out in early spring.
How to Direct Seed Collards
Directly seeded collards work best for fall and winter plantings, but you can also direct sow in the spring. It’s best to sow collards in the garden from early spring through July (or about 3 months before the expected first frost). This ensures that they have enough time to mature before the frost and will be ready to provide those cold-sweetened leaves into the cooler months. Seed earlier in areas where heavy freezes occur sooner.
For bunching or large leaf harvests, collard seeds can be planted in groups of 3-4 seeds every 12-18” in rows 18-36” apart. They should be sown about ½” deep, gently covered with soil, and kept consistently moist until germination. Once cotyledons have emerged (typically after 6-12 days), thin collards to 1 plant per group to prevent overcrowding.
If you prefer baby collards, sow about 60 seeds per foot in a 2-4” wide band. They can be buried about ¼” to ½” deep and don’t need to be thinned. Keep in mind that baby greens have a shorter harvest window and may bolt quickly in heat due to crowding stress.
How to Seed Collards Indoors
If you prefer to get a head start on collard seedlings in the early spring or to transplant in the fall, the seeds are best sown indoors in 50 or 72-cell plug flats. Fill your plugs with a high quality organic seed starting mix that is well-drained with perlite or vermiculite.
Plant 2 seeds per cell about ½” deep and gently cover with more potting mix. Keep soil temperature over 75°F until germination by using a heating mat. Once seedlings emerge, the heating mat can be removed and air temperatures can be reduced to around 60°F. Thin to 1 plant per cell and allow to mature for 4-6 weeks before transplanting.
Planting collard greens is the same as any other vegetable seedling. Whether you buy your plant from a nursery or grow them yourself, the process will be the same. Preparing your beds with 2-4” of quality aged compost and loosening the soil with a garden fork is a great way to give your baby plants a boost as soon as they get into the garden.
If you plan on companion planting, consider adding vegetables that will not compete with the same nutrients. Some great options for companion planting collards would be garlic, mint, or chamomile.
Harden Off Seedlings
Collards aren’t nearly as finicky as other garden crops, however they still benefit from being “hardened off” or adjusted to outdoor temperature fluctuations before they are planted in the ground. It also helps to slightly cut back on watering to allow the plants to get used to less tending. Consider this process kind of like preparing your kid to go off into the adult world. They start in a college dorm room and later graduate to living on their own. But they need time to adjust!
Place seedlings in a slightly protected area (still with full sunlight) outdoors and let them acclimate to night time temperatures for 5 days to a week before planting. Bring them inside if temperatures get close to freezing, as collards need to be mature and established to properly deal with frost.
How to Transplant Collards
Once hardened off, collards are ready to transplant. The ideal spacing for bunch-sized collard plants is 12-18” between plants and 18-36” between rows. Ideally the temperatures should be between 55° and 75°F, but they will still produce good crops in hot weather.
Use a garden trowel or hori hori to make a planting hole a little bigger than your collard plugs. Grasp the seedling gently by the base and wiggle it out of the cell, placing into the hole and backfilling just to the soil line (careful not to bury the base of collard greens like you do with tomatoes).
Water in with a diluted kelp solution to help with transplant shock. I also like to drape a thin piece of row cover over the top to add a little extra protection from cold and pests during the establishment phase.
How to Grow Collards
Growing collards is straightforward and fairly hands-off once they are established. The secret is choosing regionally-adapted varieties, ensuring proper spacing, and providing moderate water. Regular harvests also keep collards going strong all season long.
Like all brassicas, collards require full sunlight and should never be planted in shady parts of the garden. Though they like cool weather, they will tolerate hot sunny days in the summer as long as they have plenty of moisture. Avoid planting collards in a place where they may get shaded out by trees or buildings.
Collards have moderate watering needs, typically needing a thorough drench about once a week if it doesn’t rain. Young plants are especially thirsty and need plenty of consistent moisture to establish their deep roots. Drought stress will inevitably produce lower quality collard leaves that may be tough or more rubbery in texture. For flavorful, tender leaves, aim for consistent irrigation and the cool-weather growing season.
To determine if you need to water, stick your finger in the soil near the base of collard plants. If your finger comes out clean, the soil is probably dry and the plants are thirsty. Collards will also readily wilt and let you know that they need some water in the heat of the day.
However, you should avoid drenching them or making the soil soggy. Water pooling up at the base of a collard plant is a bad sign and can cause a whole host of disease problems.
Collard roots can reach depths of 2 feet or more, so it is very important to grow them in good, well-drained soil that is loose and rich in organic matter. The ideal pH is between 6.0 to 7.5. Amending with compost or aged manure is the easiest way to fix overly sandy or heavy clay soil.
I also prefer to use a broadfork to loosen the lower levels of soil without tilling or disrupting the fragile soil ecology. Heavily tilled or damaged soil without good structure can result in compaction layers that severely limit crop growth, including collards and most garden vegetables. Aeration and fluffy quality compost is the key to yummy, happy greens.
Climate and Temperature
Collards are a cool-weather crop that thrives best in temperatures between 60° and 70°F, however they will tolerate down to the teens (if mature) and up into the 90s (if provided enough water). This makes them perfect for southern fall, winter, and spring plantings. In the north, collards do well in the summer and fall. Avoid exposing baby collard plants to temperature extremes without protection.
When it comes to plant nutrition, collards aren’t super needy. A quality nitrogen-rich organic fertilizer like liquid fish, feather meal, aged manure, alfalfa meal, blood meal, or nitrogen fixing plants like legumes are all great options for growing abundant leafy greens. Provide a dose of fertilizer at the time of planting and again in the mid-season to promote vigorous growth.
Collard plantings should be kept properly weeded to prevent too much competition. I usually avoid using harsh hoes that may disrupt the root zone, so hand pulling or surface-level scuffle hoeing are best.
About 2 months after planting you can begin harvesting your collard greens by clipping individual leaves. Once they are a bit bigger and more robust, you don’t need a knife or scissors. You can simply pull back outer leaves and snap their stems from the central stalk. Leaves will continue growing from the center all season long.
Collard leaves can be eaten at any stage, but I find they have the best texture and flavor at a medium 6-10” length. Too small and they may be too tender for cooking. Too large, and the stems start to get woody.
Collards are very hardy and actually reach their prime in late fall after the first light frosts. Protecting with row cover will extend your harvest window and allow you to continue enjoying the frost-sweetened greens.
Best Varieties of Collards
There have been lots of advancements in the realm of traditional plant breeding, particularly for vegetables like collards. There are many lovely heirloom as well as hybrid varieties on the market with great vigor, disease resistance, and delicious flavor. Depending on your climate, you may wish to select certain varieties that are known to perform best in the weather of your region.
Northern Climate Varieties:
- ‘Cash Crop’: This quick-maturing Georgia-type collard hybrid takes 50 days to begin harvesting and performs well in early spring or fall. The plants are tall, medium-green, and slightly curly around the edges.
- ‘Vates’: A classic open pollinated variety with exceptional cold tolerance that will overwinter in tunnels or greenhouses in the north. Plants are large and upright with crumpled leaves and mild cabbage-like flavor. 60 days.
Southern Climate Varieties:
- ‘Georgia’: A favorite amongst southern growers, this heirloom is perfect for early spring or late summer plantings. The plants have a mounding habit and smooth, juicy, blue-green leaves that take 65-70 days to be ready to harvest. It is more compact with a 12” spread and 25-30” height.
- ‘Top-Bunch’: A Georgia-type hybrid that provides the earliest harvest. Plants are tall and super productive, with medium-green slightly crinkled (“savoyed”) leaves that are very attractive at farm stands and on platters. 50 days to mature.
- ‘Flash’: This slow-to-bolt hybrid has smooth dark green rounded leaves that yield in great abundance. It takes about 55 days to mature to harvest size and tolerates warmer summer weather.
Pests and Diseases
Anyone who has grown collard greens in the south knows that they can be a magnet for the same pesky bugs that attack our kale, cabbage, and other brassicas. Fortunately, organic control or exclusion (with row cover) is very simple and effective.
These annoying white-to-green oval-shaped bugs will suck the sap of your collard plants, leaving behind unsightly holes and a sugary sticky substance that can attract ants. Aphids are most often found on the undersides of collard leaves. To dislodge them, use a heavy blast of water onto the leaves.
To prevent and treat infestations, dispose of the most damaged leaves and use a diluted neem solution to repel and kill remaining aphids. Planting an insectary of white alyssum, flowering dill, yarrow, and other beneficial plants can also help keep aphid populations under control by attracting ladybugs and other predators.
If you spot green caterpillars with white stripes on your collards, you probably have a cabbage looper problem. These butterfly larvae are exceptionally good at blending in with the leaves and chomping holes all over your collard greens. You may even spot their gross greenish balls of poop, called frass.
To get rid of cabbage loopers, you have a few options. Hand pick them, apply Bt (bacillus thuringiensis, a soil bacteria that attacks caterpillars), or use row cover to prevent the adult moths from laying eggs on your collards in the first place. I prefer the last option because row cover keeps other pests like flea beetles out of my collard patch from the time of planting.
Black Rot and Black Leg
These nasty seed-borne diseases are better prevented than treated. Source disease-free tested seeds from reputable seed companies and practice good sanitation by removing brassica plants and crop residue at the end of the season instead of letting it decay in the garden.
Now for the delicious part! Collard greens have a wide array of delicious culinary uses. The leaves are most often used, sometimes with the stems removed. I find that the stems are a nutritious source of fiber, so I prefer to strip the rest of the leaf away and dice the stems extra small for cooking.
A few tasty ways to enjoy collards include:
- Braised collard greens (simply cut and pan-cooked with broth or water and salt)
- Southern collard green stew (like the infamous “pot likker”) with cornbread
- Collard green wraps (a great tortilla or gluten substitute)
- Bacon roasted collard greens
- Olive oil and collard sauté
- Ribbon-cut and tossed in any soup or stew
- As a substitute in any recipe that calls for kale
Frequently Asked Questions
What exactly are collard greens?
Collard greens are a cabbage-family vegetable most often grown for their large blue-green smooth leaves and subtle cabbage-like flavor. Famous for their use in southern cuisine, collard greens are an underrated superfood equivalent to kale.
How long does it take to grow collard greens?
Collard greens take 50-80 days to mature, depending on the variety and growing conditions. For quicker harvests, collard seeds can be started indoors in the early spring and transplanted into the garden.
Do collard greens grow back after cutting?
Collard greens are the gift that keeps on giving in the garden! You can harvest outer leaves by gently pulling the stems down away from the central stalk, allowing inner leaves to continue growing. Collard greens will re-sprout and regrow all season as long as their roots are not disturbed.
What month do you plant collard greens?
Collards are a cool-weather crop that can be planted in the early spring (March to May) in most regions or in late summer for a fall harvest.
I honestly think kale gets way too much hype compared to collard greens. The gorgeous smooth leaves are so delicious and among the easiest garden vegetables to grow. Plus, there’s never any harm in adding more diversity to your brassica garden plantings.