Collard Greens vs Wolffia: A Southern Classic Meets Its Match

	Cooked Collard Greens (per 100g)	Wolffia globosa
Calories	About 32 kcal	Low
Protein	About 3g	More than 45% of dry matter*
Protein quality	Has essential amino acids, but in small amounts	All 9 essential amino acids, PDCAAS of 89%*
Vitamin B12	Essentially none	Naturally occurring, bioactive forms*
Vitamin K	Extremely high	Low
Fiber	About 4g	Contains dietary fiber
Oxalates	Low (much lower than spinach)	Zero

Now let's break it down round by round.

Round 1: Protein

This is where things get lopsided.

One cup of raw collard greens has about 12 calories and roughly 1 gram of protein. Cooked, collards give you around 3 grams per 100g. That's great for leafy vegetables, but you'd need to eat a small mountain of cooked greens to build a meal around it.

Wolffia plays a different game. Research on Mankai found it's more than 45% protein by dry weight, with a protein digestibility score (PDCAAS) of 89%.

In a randomized controlled trial with 36 men, a Wolffia meal raised blood levels of several essential amino acids in a similar way to meals made from soft cheese and green peas.

So yes, collard greens contain protein. Wolffia is protein. Huge difference. Adding it to any drink makes it almost a superfood protein shake.

Winner: Wolffia 🏆

Round 2: Vitamin B12

This is the round that honestly made my brain short-circuit when I first learned about it.

Leafy vegetables, collards included, basically don't contain vitamin B12. Plants don't need it, so they don't make it. That's why people eating mostly plants and vegetables usually end up on a supplement.

Researchers found that Mankai contains the actual bioactive forms of B12, with no "pseudo B12" (the inactive version that shows up in some algae). In an 18-month trial, people had a green shake with 100g of frozen Mankai a day, and their B12 levels held up and rose instead of dropping.

A plant with real B12.

Still wild to me.

Winner: Wolffia 🏆

Want the deeper dive? I wrote more about plant-based B12 sources here.

Round 3: Minerals and Oxalates

Here's something most nutrition articles skip.

Plenty of dark green leaves contain oxalates. In food science terms, these are compounds that bind to minerals like calcium and iron and make them harder to absorb. Spinach is the famous offender.

Collard greens deserve credit here. They have much lower oxalate levels than spinach, so the calcium in collards is more usable.

Wolffia globosa has zero oxalates. It also packs a lot of zinc and iron for its size, more than most leafy greens or vegetables. In a nutrient analysis comparing dried samples, duckweed had about 15 mg of zinc per 100g, versus 3.2 mg for kale and 5.5 mg for spinach.

And in a study on rats, iron from Mankai was about as effective at restoring hemoglobin as an iron supplement (ferrous gluconate). Wolffia ranks among the top vegan protein supplements.

Winner: Wolffia, with collards a respectable second 🏆

Be One of the First to Try Wolfa

I'm not going to pretend I've got my nutrition figured out. Most days I'm too busy (or lazy) to cook a pot of collards for an hour. That's exactly why I'm bringing Wolffia to America. It's complete plant protein and natural B12 from a single, traceable farm in Thailand, and all you need is a spoon. We're still pre-launch, so the waitlist is the only way to get first access. Join the waitlist at mywolfa.com and I'll let you know the second it's ready.

Where Collards Actually Win

I promised honesty, so here it is.

• Vitamin K: collard greens are a monster here. Wolffia doesn't come close.
• Fiber: cooked collard greens bring about 4 grams per 100g.
• Vitamins A and C: collards are loaded, with significantly more vitamin A and calcium than broccoli.
• Choline: cooked collards contain significantly higher levels than raw ones, and collards edge out kale (even lacinato kale) on fiber, calcium, and choline.

Collards also have a strong antioxidant and anti-inflammatory profile. They're genuinely one of the most nutritious cooked greens you can put on a plate.

Winner: Collards 🏆

What Is the Healthiest Dark Leafy Green?

People ask me this a lot, and the honest answer is: it depends on what you're missing.

Spinach (cooked or raw) has more magnesium and potassium than collards, plus folate, iron, and vitamins A and C, though the oxalates get in the way. Kale is exceptionally high in vitamins K, A, and C. Swiss chard, rainbow chard, and beets (the greens on top) bring magnesium and potassium too. Cabbage is the budget all-rounder. Cooked collard greens win on calcium and fiber. Lettuce and most mixed greens are lovely in a salad, but they're mostly water.

Most leafy greens are amazing for vitamins and minerals. What they usually lack is serious protein and B12.

Technically, Wolffia isn't in the traditional leafy greens category. It's an aquatic plant, basically one tiny floating leaf. But if you're asking which green thing fills the gaps other leafy greens leave behind, that's where my vote goes.

Cooking Time, Texture, and Taste

This is where my lazy side really kicks in.

Collards Take Patience

Collards are hearty dark green vegetables, and their flavor mellows as they're cooked. But the cooking time is long.

The classic Southern cooking method is slow braising. Strip the tough stems, stack the collard leaves, roll them up, and cut them into thinly sliced ribbons. Sauté finely chopped onions and garlic. Then add the greens with ham hocks or other cured pork, chicken broth, a pinch of salt, and crushed red pepper. Let the slow cooking do its thing for an hour or more until the greens are tender. Finish with a splash of vinegar and more salt to taste.

(Want it meat-free? Swap in olive oil, extra garlic, and vegetable broth instead of chicken broth. Short on time? Some cooks blanch the leaves in boiling water first to cut the cooking time a little.)

Properly cooked, the result is incredible. The leftover liquid, called pot likker, is its own thing entirely.

But that's a lot of chopping, simmering, and dishwashing for a Tuesday.

Wolffia Takes a Spoon

Wolffia has a neutral, mild flavor and a soft, smooth texture. There's nothing to stem, chop, or cook.

Stir it into yogurt. Blend it into a smoothie. Fold it into soup or pasta right before serving.

That's it. That's the recipe.

Why Are Collard Greens So Central to Black Southern Cooking?

You can't talk about collards without talking about where they come from culturally.

Collards arrived in the American South from Europe, but the way they're cooked comes largely from Black cooks. Enslaved Africans brought West African traditions of stewing leafy greens. On plantations, they were often left with greens and scraps like ham hocks. They turned that into slow-simmered, deeply flavored dishes, and they saved the nutrient-rich pot likker instead of tossing it.

That tradition became a pillar of soul food and Southern cuisine as a whole, from Georgia to South Carolina. Collard greens are still a New Year's Day staple in many families, eaten for prosperity (the green leaves stand for money).

So when people say collards are "just a vegetable," they're missing a big part of the story.

What Are Collard Greens Called in Spanish?

In Spanish, collard greens are often called berza, and sometimes just col (the general word for cabbage). Names vary by region, so what you hear in a Mexican market can differ from what you'd hear in Spain or South America.

The Best Substitute for Collard Greens

Out of collards, or want other greens that cook faster? Here's what's comparable.

Kale

Kale is the best substitute for collard greens in cooking. Lacinato kale (also called dinosaur kale or Tuscan kale) has flat leaves that are more tender than collards and braise beautifully. Dinosaur kale also cooks faster than collards, and lacinato kale keeps its texture. Curly kale works too, but its texture is more ruffled and the flavor is a bit more peppery. If a recipe calls for collards, lacinato kale is my first pick.

Swiss Chard and Rainbow Chard

Swiss chard cooks down in 3 to 5 minutes, which makes chard way faster than collards. Rainbow chard, with its red, pink, and yellow stems, swaps in the same way. Chard and beets are closely related (same species), so chard tastes milder and a little earthy, like the greens from beets.

Quick tip: chop swiss chard stems and cook them a couple of minutes before the tender leaves go in. Rainbow chard stems look gorgeous sautéed in olive oil with garlic.

Turnip Greens and Mustard Greens

These are the traditional Southern substitutes. Cooked turnip greens are slightly bitter and tender. Mustard greens are more peppery, with a real mustard bite. Try mustard greens cooked with onions and a little vinegar. Many cooks mix collards, turnip greens, and mustard greens in the same pot.

Cabbage, Bok Choy, and Gai Lan

Cabbage has a similar brassica flavor and holds up to long cooking. Savoy cabbage is the closest match for texture. Bok choy and gai lan (Chinese broccoli) bring tender leaves, dark green color, and crunchy stems for quick stir-fries. Baby bok choy has the most tender leaves of the bunch. Discover more substitutes for bok choy.

And if you want to boost the protein in any of these dishes? Add a spoonful of Wolffia at the end. It's not a swap for greens. It's an upgrade on top of them.

Growing Collards vs Growing Wolffia

This part surprised me the most.

Growing Collards

Collards are a cool season crop, best planted in early spring or fall. Collards thrive in well-drained, loamy soils rich in organic matter, though they'll handle sandy soils too.

Plant seeds 1/2 to 3/4 inch deep in moist soil, and space them 15 to 18 inches apart for full-grown plants. An early spring planting gives you greens by summer. A light first frost actually sweetens the flavor, which is why gardeners in northern states love them.

The best part is that you can harvest the same plant multiple times. Just pick the outer leaves and let the center keep growing. NC State Extension publications are a great place to start if you want to grow your own.

To store collards, wrap unwashed leaves in a paper towel and keep them in a plastic bag in the fridge.

Growing Wolffia

Wolffia grows on water. No soil, no acres of farmland, and very little water compared to leafy greens grown in fields.

And it grows ridiculously fast, doubling its mass in just a couple of days.

That's the side of this plant that makes me think we'll see Wolffia farms on Mars one day. (I'm only half joking.)

Curious about the plant itself? Here's more on the world's smallest flowering plant.

So Who Actually Wins?

Let's tally it up.

Collards win on: vitamin K, fiber, vitamins A and C, choline, and centuries of flavor and culture.

Wolffia wins on: protein, protein quality, natural B12, zero oxalates, zinc, sustainability, and the fact that you don't have to cook it.

For me, it's Wolffia, and not just because I'm biased (okay, a little because I'm biased).

Here's why. Cooked collard greens are incredible, and I'd never tell anyone to stop eating them. But they're a side dish. Wolffia fills the exact gaps most leafy greens leave open: complete plant protein and real B12, with zero prep.

There's also some early clinical research worth knowing about. In a small crossover trial, a Wolffia shake was linked to a lower blood sugar peak after dinner compared to a matched yogurt shake, and participants rated it slightly more filling. You can read more about complete plant protein sources here.

Want to try it? I'm working with one of the top Wolffia farms in Thailand on a formulation that tastes great. You can join the waitlist at mywolfa.com to be first in line.

Where I Land

Eat your collards. Seriously. Braise them with garlic and red pepper, drink the pot likker, keep the tradition alive.

Then add a spoonful of Wolffia to your yogurt the next morning.

Best of both worlds.

And honestly? No dishes.