Learn How to Grow Collard Greens in Containers Step by Step (From Seed to Harvest)

It started with a single leftover seed packet. The ground outside was rock-hard clay, so the only space left was an old 5-gallon bucket on the porch. I filled it with compost, pressed in a few seeds, and hoped for the best. A month later, those tiny sprouts were thick, dark collard leaves! Proof that growing collard greens in containers works even when the soil and space don’t. All you really need is good soil, sunlight, and a pot of some sort.

Collards are easy to grow, even in pots. Give them a deep container, consistent moisture, and a tiny bit of attention, and you’ll get months and months of harvests. It’s the perfect solution when you’ve got crappy soil or no space. Or you just want them closer to the kitchen instead of way out the back!

Here’s how to get it done.

How to Plant Collard Greens In Containers

Planting collards in containers is easy, just follow my simple starting tips below. You’ll be harvesting your own crop in no time! Further down, we’ll go through the best ways to grow them well, how much to water, and what kind of soil to use.

When to Plant Collard Greens

Collard greens are cool-season crops. Here are the best times to plant them:

• Southern U.S. (Zones 8–10): Plant in late summer to fall for a winter harvest, or again in late winter for spring growth.
• Northern U.S. (Zones 4–7): Start seeds 4–6 weeks before the last frost indoors, or direct sow outdoors 2–4 weeks before the last frost.

They tolerate frost well and taste even sweeter after light frosts.

The Best Container for Growing Collard Greens

Choose a sturdy pot or grow bag made of fabric, plastic, or glazed ceramic. Collards are heavy feeders with large root systems, so they need both depth and width.

• Make sure your containers have good drainage holes. Soggy soil leads to root rot.
• Fabric grow bags (5–10 gallons) work great for air pruning and moisture control.

What Size Pot for Collard Greens

Each plant needs at least 12–14 inches of depth and width, but bigger is better.

• One collard per 5-gallon pot (minimum).
• A 10–15 gallon container can support 2 to 3 plants comfortably if you fertilize enough.

If you crowd them, you’ll get smaller leaves, which can actually be nice for tender baby greens.

The Best Soil for Growing Collard Greens in Pots

Use a rich, well-draining potting mix, not garden soil. Look for:

• 50% high-quality potting mix
• 25% compost (worm castings or mushroom compost)
• 25% coconut coir or peat moss for moisture balance

Amend with a slow-release organic fertilizer high in nitrogen (like blood meal or feather meal) to encourage leafy growth. Collards are heavy feeders! Top up with liquid fish emulsion or seaweed every 2 to 3 weeks.

When to Plant for Successive Harvests

For continual harvests, stagger plantings every 2 to 3 weeks. In mild climates, you can grow them almost year-round. Just give them afternoon shade in summer heat. If you’re in a frosty zone, grow them in spring and fall.

How Deep Should You Plant Collard Green Seeds or Seedlings

• Seeds: Sow about ¼ to ½” deep. Cover lightly with fine soil, and keep moist.
• Seedlings: Plant so the soil line matches the top of the root ball – not deeper. Water immediately after transplanting.

How Many Collard Greens per Pot

• 5-gallon pot: 1 plant
• 10-gallon pot: 2 plants
• 15-gallon pot or larger: up to 3 plants (if well-fed and spaced at least 12 inches apart)

Crowding them reduces airflow and increases the risk of pests like aphids or cabbage loopers. Err on the side of more space, especially if you’re in a humid region.

How to Grow Collard Greens In Containers

Let’s take a look at what collards need to grow well in containers, including how much sun they need, when to water them, and the best types of fertilizers!

What Do Collard Greens Need to Grow Well in Containers

Collards are tough plants but they thrive when you give them steady moisture, rich soil, and full sunlight. In pots, the main things to look out for are nutrients and water. These run out water in pots than they do in the ground.

To keep your plants thriving:

• Use deep, nutrient-rich soil with excellent drainage.
• Feed them regularly (every 2 to 3 weeks is great).
• Keep them evenly moist. Don’t let them get bone dry or waterlogged.
• Give them at least 6 hours of direct sun daily. Collards love sun!
• Rotate or move your pots every few weeks if they start to lean or grow unevenly toward the light.

They’re happiest in cool temperatures (55 to 75°F), but they’ll handle heat if you give them some shade and keep them well-watered.

How Much Sun Do Collard Greens Need

Collards need full sun. Ideally, they should get 6 to 8 hours of direct light each day.

If you live in the southern U.S., a bit of afternoon shade helps prevent stress and bitterness during hot spells. If you’re in northern zones, full sun all day gives you the best leaf size and yield.

You can even grow them on balconies or patios as long as they get several hours of unfiltered sunlight.

How Much Water Do Collard Greens Need

They like consistently moist soil, but not soggy. Water when the top inch of soil feels dry. It’s easy to check – just poke your finger in! In containers, this often means:

• Spring/Fall: 2 to 3 times per week
• Summer heat: daily or every other day. Containers dry out much faster than ‘actual’ soil. Don’t let them get bone dry or it becomes almost impossible to re-wet the soil. You can add some water retention crystals if it becomes too hard to keep up with.

Use mulch (like shredded leaves or straw) on top of the pot to keep the roots cool and keep moisture where you want it. If you see the leaves drooping in the middle of the day, that’s a good sign you need to water your plants. They’ll perk right up by evening!

What’s the Best Fertilizer for Collard Greens in Pots

I can’t say this enough – collards are heavy feeders! They’ll gobble up nutrients fast in a container.
To keep your plants looking fantastic and healthy:

• Start with a balanced, slow-release fertilizer at planting time (something around 10-10-10 or organic equivalent).
• Boost the nitrogen every 2 to 3 weeks with a liquid fertilizer like fish emulsion, compost tea, or a water-soluble vegetable fertilizer (something like 5-10-5).

If the lower leaves start yellowing, that’s a sign they need more nitrogen. Regular feeding keeps the leaves yummy and productive for months.

Do You Need to Prune Collard Greens in Pots?

Nope, they don’t need pruning, but they do prefer some maintenance. Here’s how to go about it:

• Harvest outer leaves first and leave the center to keep growing. This encourages continuous production and keeps the plant tidy.
• Get rid of yellow or damaged leaves to improve airflow and prevent mildew or other pests.
• As the plant gets older, you can also pinch off the lower leaves to promote new growth on the top. This can also help reduce aphid buildup.

If you grow your collards long-term, they can become tall and woody (especially in warm climates). Don’t hesitate to cut them back by one-third if they get leggy! They’ll bounce right back with new shoots.

How to Grow Collard Greens From Seed In Containers

Here is a step-by-step guiding to growing your own collard greens from seed!

1. Pick your planting Time

• Zones 8–10 (South): Sow late summer to fall for a winter harvest, or late winter for a spring harvest.
• Zones 4–7 (North): Sow 2 to 4 weeks before the last frost outdoors (they’re frost-hardy) or 4 to 6 weeks before the last frost indoors and move them out after hardening off.

2. Choose the container (and how many seeds)

• Choose a 5 to 10 gallon pot or fabric grow bag with strong drainage. The bigger the better. You can grow one plant in a 5-gallon pot, 2 plants in a 10-gallon pot, and 3 plants in a 15-gallon pot.
• If you want to sow your seeds directly in the final pot, drop 2 to 3 seeds into each hole. You can then thin them out to the strongest plants.

3. Mix a seed-friendly potting blend

• Use a high-quality potting mix (not garden soil).
• For strong starts: ~60% potting mix + 20% compost + 20% coco coir/peat.
• Pre-water the mix (before sowing your seeds!) so it’s evenly damp. A bit like a wrung-out sponge.
• Optional but helpful: Mix in a gentle organic starter fertilizer or a small pinch of worm castings. Collards like a nutrient baseline straight away.

4. Fill and firm

• Fill the pot to 1 – 2 inches below the rim.
• Tap the sides to settle the mix. You want good contact, not compacted brick.

5. Sow the seeds at the right depth

• Make shallow holes with a finger or dibber, ¼” to ½” deep.
• Space your seeds around 12–14 inches apart. Or, you can thin your plants once they sprout to achieve this spacing. In a 10-gallon pot, for example, you’d make two holes in each side of the pot. Not right at the sides because the soil tends to get dryer around the edges, but close to it so the plants have enough spacing between them.
• Drop 2 to 3 seeds in each hole and cover them lightly.
• Water gently to settle the soil and seeds.

6. Label and cover (lightly)

• Label your container with the variety and the date of planting. Sometimes, it can feel like it’s taking ages for seeds to sprout, only to realize it’s been days – not weeks!
• Optional: Lay a thin layer of vermiculite or fine mix on top for even moisture.
• Don’t plastic-wrap the pot – collards like air flow. If the air is very dry, you can use a vented dome to help them germinate. Just make sure you remove it the moment you see sprouts!

7. Warmth and light

• Germination temp: Best at 60 to 75°F. They’ll sprout in 4 to 10 days. Your seeds germinate even quicker if the temp is near 70 to 72°F.
• Light: As soon as they break the surface, give the 6 – 8+ hours of direct sun or 14 – 16 hours under grow lights. If you use grow lights, put them 2-3″ above the leaves.
• Turn the pot or raise/lower the grow lights to keep your seedlings strong and stocky. We’re not aiming for leggy! No Barbie collards for us, thank you very much.

8. Water

• Keep the top ½ inch of the soil moist, not soggy.
• Bottom-water if possible. Place the pot or tray in a shallow pan of water for 10 to 20 minutes, then drain. This reduces damping-off disease.
• Mulch very lightly once your seedlings are 2 to 3 inches tall (fine bark, straw snips, or shredded leaves).

9. Thin the seedlings (save the extras for microgreens)

Once your seedlings have developed their first or second true leaf, thin each spot to one plant (the best one!). You can gently snip them off at ground level. Eat these little ones as mild and tasty microgreens!

10. Hardening off (if you started indoors)

Over 7 to 10 days, ease your babies outside:

• Day 1 – 2: One to two hours in a shady position
• Day 3 – 4: Two to three hours of morning sun
• Day 5 – 6: Four to six hours of mixed light
• Day 7+: Full day.

Starting Collard Seeds Indoors In Trays

You can get a headstart to the growing season by starting your collard greens indoors. Follow these simple steps:

1. Fill a 6-cell tray with seed mix and sow 2 seeds per cell, ¼ inch deep.
2. Aim for a temp of 70°F and bright light. Your seeds. will germinate in 4 to 10 days.
3. Thin to one seedling per cell.
4. If the roots fill the cells before it’s time to go outside, you can pot your seedlings into 3-4″ pots.
5. Harden off and transplant your collards into their final containers when they have 3 to 4 true leaves. Make sure you keep the same soil line (don’t bury the stems).

Can You grow collard greens indoors?

Yes! You can definitely grow collard greens indoors, but you do need the right setup. Collards are big, leafy plants and they do prefer full sun and cool air. Success depends on mimicking those outdoor conditions as best as you can inside your home.

Without strong light, your plants will stretch and get leggy. They might lose flavor, too. Most likely, they won’t grow as big indoors as they would outdoors, but you’ll still get to harvest plenty. If you’d like to give it a try, here’s how to get it done!

How to Grow Collards Indoors (Successfully)

1. Choose the Right Light

This is the make-or-break step.

• Use a full-spectrum LED grow light that mimics daylight (5000 – 6500K).
• Keep lights 2–4 inches above the leaves and on for 14–16 hours per day.
• Without grow lights, collards will grow weak and floppy, even in a bright window.

2. Pick Compact Varieties

Some varieties handle pots and limited light better than others. Some good options include Vates and Georgia Southern. Vates is compact with dark leaves and great for containers. Georgia Southern has big, broad, but tender leaves and tolerates indoor temps well.

3. Use a Large Enough Pot

Indoors, they still need space. Choose a 5-gallon minimum container per plant. Fabric pots are great because they drain exceptionally well, and they’re breathable.

4. Temperature and Airflow

• Keep room temps between 60 – 75°F.
• Collards actually prefer cooler nights (down to 50°F), which helps flavor.
• Use a small fan to improve air flow and reduce the risk of mold and mildew.

5. Watering Indoors

Indoor air is drier, so keep an eye on your soil and water when the top inch feels dry. Don’t overwater. If you use saucers, drain them regularly so the roots don’t continuously sit in water.

6. Feeding

Because containers indoors can’t flush naturally, use a diluted organic fertilizer (like liquid fish or seaweed) every 2 to 3 weeks. Skip anything high in salts! Salts build up and burn roots.

7. Harvesting

You can start cutting the outer leaves once the plants are about 8 – 10 inches tall. The center keeps growing, so you can harvest for months. Indoor-grown leaves tend to be smaller but very tender.

Enjoy!

Companion Plants for Collard Greens In Containers

Collards belong to the Brassica family, which means they’re heavy feeders and pull lots of nitrogen. Other plants in the same family include cabbage, kale, and broccoli, as examples. Their roots and canopy take up space fast. What this all means is that you can companion plant with collards, but you need to choose plants that are light feeders and pest repellers. Not other nutrient hogs!

If you, for example, tried to cram a bunch of Brassicas together, like collards, kale, and cabbage, they’ll all compete and your yields will drop. The trick is to think vertically and seasonally – short-term herbs, flowers, or shallow-rooted companions.

Good Companions for Collards in Containers

1. Dill

Dill attracts beneficial insects like ladybugs and parasitic wasps that eat aphids and cabbage worms. These are two of collards’ biggest pests. Sprinkle a few dill seeds around the edges of the pot. They’ll grow tall and feathery, and don’t interfere much with the collard’s root zone.

2. Chamomile

Chamomile is said to improve the flavor and growth of leafy greens and attract pollinators if you’re growing other flowering plants nearby. It also has shallow roots, so it won’t steal much nutrition.

3. Mint (in moderation)

Mint’s strong smell repels cabbage moths and flea beetles. A word of caution, however. Mint can spread aggressively. In a container, either plant a tiny rooted cutting in one corner or grow it in its own mini pot nearby for the scent benefit without the takeover.

4. Chives or Green Onions

The sulfur compounds in chives and green onions naturally repel aphids and certain worms. Plant them along the pot’s edge where they won’t compete much for vertical space.

5. Nasturtiums

Ah, Nasturtium! This would have to be one of my all-time favorite companion plants. For just about anything! It’s the sacrificial lamb. They attract aphids away from your collards and look gorgeous doing it! Tuck one seed near the rim of the container. It’ll trail over the side and not crowd the collard.

6. Lettuce or Spinach

Lettuce and spinach have shallow roots and they’re quick to harvest. They also enjoy the light shade from the collard’s leaves. Sow a few seeds early on and harvest them before the collard greens reach full size.

Bad Companion Plants for Collards In Pots

1. Other Brassicas

Cabbage, kale, broccoli, cauliflower…. These all share the same pests and require the same nutrients. Planting them together just attracts cabbage worms and forces the plants to compete for nutrients. Not a good idea.

2. Beans and Peas

Beans and peas are legumes. Legumes fix nitrogen (which is awesome), but they also prefer less acidic, less rich soil than collards. This combination can hinder both plants’ growth, especially in confined pots.

3. Strawberries

Strawberries don’t enjoy the nutrient draw or shade that collards create.

Collards as Companions for Other Plants

Collards aren’t known to be the ultimate companion plant, but they can do a few subtle things:

• Their big leaves create shade that you can use to protect tender greens or herbs from harsh summer sun.
• After harvest, their used soil is rich in organic matter, making it a good base for replanting quick crops like lettuce or radishes.
• If you let them flower (in long-term pots), collard blossoms attract hoverflies, bees, and predatory wasps, which improves the overall biodiversity in your container garden.

Example Companion Container

Here’s a reliable setup that looks good and works:

• 1 collard in the center (5–10 gallon fabric pot)
• 1 nasturtium trailing over the side
• 1 clump of chives or a few dill sprigs at the edge
• Optional: scatter a few lettuce seeds under the canopy for shade-tolerant greens

That combo creates a mini ecosystem! You’ll get pest control, visual appeal, and a super-efficient use of space.

When to Harvest Collard Greens In Containers

Collards grow fast once they settle in, and you don’t have to wait for the whole plant to mature before picking. Here’s how to get the most out of your plants.

• Early harvest (baby leaves): About 30 to 40 days after planting.
• Full-size leaves: Around 55 to 75 days after planting, depending on the variety and weather. Cool weather sweetens the leaves, so the best harvests often come in late fall, winter, and early spring in mild regions.

In southern states (Zones 8 – 10), you can harvest nearly all winter. In northern zones (4 – 7), pick before the hard freezes or grow them indoors or under cover to extend the season.

How Long Does It Take to Grow Collard Greens

Growth Stage	Timeline (Days)	Notes
Germination	4 – 10 days	Warmer soil = faster sprouting
Baby leaves	30 – 40 days	Tender, perfect for salads
Mature leaves	55 – 75+ days	Full flavor and size
Harvest window	Continuous for months	Pick outer leaves only

They’ll keep producing new leaves from the center as long as you don’t cut the growing tip. One healthy plant in a container can feed you for months.

How to Know When It’s Ready to Harvest

You can start harvesting once the leaves are large enough to use. Typically, that’s around 8 to 10″ long. A few clear signs:

• Color: Deep, even green. Pale leaves can mean nutrient deficiency or too little light.
• Texture: Crisp but flexible. Not tough or leathery. If they’re tough, you may have left them too long.
• Size: For baby collards, pick 3″ – 5″ leaves; for cooking greens, 8″ – 10″ leaves are ideal.
• Collards actually taste better after a light frost. Sugars concentrate in the leaves, which reduces bitterness. If you’re in a cooler zone, wait until after a mild frost to harvest your first big batch.

If you see yellowing at the base, those leaves are past their prime. You can remove them so the plant focuses on new growth.

How to Harvest Collard Greens in Pots

1. Use clean scissors or a sharp knife.
2. Cut the outer leaves near the base of the stem, leaving at least 3 or 4 inner leaves untouched.
3. Don’t remove more than one-third of the plant at once. It needs leaves to photosynthesize and keep producing.
4. Water and lightly fertilize after each big harvest to encourage fresh regrowth.

Collards are a “cut and come again” crop. Keep picking outer leaves and you’ll get a constant supply. Some plants last eight to ten months before bolting in hot weather!

How to Store Collards after harvest

Once you’ve harvested, rinse the leaves right away to remove any bugs or soil. Pat them dry and store in the fridge in a breathable produce bag for up to a week. For longer storage, blanch and freeze the leaves. They freeze well and go great in soups, stir-fries, and stews.

Problems Growing Collard Greens In Containers

Collards definitely experience some problems in containers. Cabbage moths, for one, are a real issue for me. But, there are some other things to look out for as well. Here’s a list, including solutions.

Aphids and Cabbage Worms

Aphids cluster under the leaves and leave a sticky residue and curling foliage. Cabbage worms chew ragged holes through your best greens. Collards are Brassicas and their scent draws in these pests, especially in warm, still air or when your plants are stressed.

How to Fix It

• Spray aphids off with a strong stream of water every few days.
• Use Bt (Bacillus thuringiensis) for cabbage worms. It’s organic and safe for other insects.
• Add companion herbs like dill or chives to deter pests naturally.
• Keep airflow high. Stagnant indoor or patio air encourages infestations.

Yellowing or Pale Leaves

If your lower leaves fade to yellow, the growth slows, or the plant looks tired, it’s usually a nitrogen deficiency. It could also be overwatering or compacted soil.

How to Fix it

• Feed every 2 – 3 weeks with a liquid fertilizer high in nitrogen (fish emulsion or balanced veg fertilizer).
• If the soil feels soggy, reduce watering and make sure the pot drains well. If this fails, repot your plant into fresh, well-draining soil. Don’t use garden soil!
• Topdress with worm castings or compost mid-season for a long-term nutrient boost.

Leggy, Weak Plants

If your plants have long, thin stems that flop over instead of standing tall, strong, and proud, it’s probably due to too little light. This is especially a problem if you’re growing indoors or on a shady patio.

How to Fix It

• Give your plants at least 6 to 8 hours of direct sunlight outdoors, or 14 to 16 hours under strong LED grow lights indoors.
• Rotate pots every few days if one side leans toward the light.
• Pinch off the lowest leaves if the stems start to stretch. This encourages sturdier regrowth.

Wilting or Drooping

If your leaves collapse in the middle of the day, or they stay limp overnight, it’s usually a lack of water. That’s usually a problem in warm weather. It can also be caused by overwatering, which causes root rot. This can have similar symptoms.

How to fix it

• Check the moisture by sticking your finger into the soil, 1 inch deep. If it’s dry, water.
• During hot weather, collards in containers may need daily watering. Sometimes more than once a day!
• If the soil stays wet for days, lift the pot slightly off the ground for better airflow, or switch to a fabric grow bag that breathes.

Powdery Mildew or Leaf Spot

Mildew looks like white powder on the leaves. Leaf spot appears as dark, circular spots that spread over the foliage. This usually happens because of poor air circulation and humid conditions.

How to fix it

• Space plants properly. A minimum of 12 inches apart.
• Water the soil, not the leaves.
• If mildew appears, spray with a mix of 1 tsp baking soda + a few drops of dish soap in a quart (1L) of water once a week.
• Keep older yellowing leaves trimmed off to improve airflow.

Stunted Growth

If your plants just sit there without growing, it’s usually due to too small a pot, compacted soil, or rootbound plants. Collards have large root systems and need space to spread.

How to fix it

• Use at least a 5-gallon pot per plant, deeper if possible.
• Loosen the soil if it’s too dense. You can mix in compost or coco coir.
• Feed regularly. Collards are heavy feeders and will stall if they’re hungry.

Bitter Leaves

If your collards aren’t tasting as yummy as they could, and they taste harsh or peppery, it’s often caused by heat stress. Collards are cool-season plants, and their bitterness increases with high temperatures or drought.

how To Fix It

• Grow collards in spring or fall for the best flavor.
• In summer, move pots to morning sun and afternoon shade.
• Keep them consistently watered. Stress makes the flavor harsher.

Cold Damage

If you’ve checked on your plants after a hard frost and their leaves are blackened and limp, it’s probably cold damage. Collards handle frost well but not deep freezes in small pots. The roots chill faster than in-ground plants.

How to Fix It

• Bring your containers under cover (garage, porch) during hard freezes below 20°F (-6°C).
• Wrap pots in burlap or old blankets to insulate the roots. Or bales of hay/straw! These work a treat to insulate your container garden.
• Don’t harvest frozen leaves. Wait for them to thaw fully to avoid splitting or an ‘off’ flavor.

Container Problems Summary Table

Problem	Likely Cause	Fix
Yellow leaves	Nitrogen deficiency or soggy soil	Feed regularly, improve drainage
Holes in leaves	Aphids or cabbage worms	Spray water, add Bt or companion herbs
Stunted growth	Pot too small or rootbound	Use larger container, feed more
Bitter flavor	Hot temps or drought	Water consistently, move to shade
Mildew on leaves	Humidity, crowding	Space plants, water soil not leaves
Leggy stems	Low light	More sun or stronger grow lights

So, Can You Really Grow Collard Greens in Containers?

Yes! And I dare say you might even prefer it over growing them in garden beds. What started as a quick experiment in a 5-gallon bucket became a steady supply of greens right outside my door. Growing collard greens in containers gives you control over the soil quality, water, and pests, and keeps your harvest close to the kitchen.

You can start a whole container garden, and it’s rather addictive. Just check out some of my other articles on growing garlic in containers, or potatoes, or strawberries, or anything your heart (or tummy!) desires.