How to Grow Kale Microgreens: Red, Lacinato and Purple Reign

If there is one microgreen we wish more people would grow, it is kale. It is one of the easiest trays on the rack, it is ready in about a week and a half, and it gives you something no other microgreen does: a thick, soft chew, a mild flavor that does not taste like mature kale, and a scent that fills the room the second you harvest. You are not the only one who has noticed. Kale is the 6th most popular crop among growers in our Microgreen Tracker app, ahead of dozens of other crops.

Kale is also a favorite of commercial microgreen farms, and for a good reason. Many of them grow it out a little longer on purpose so the true leaves show, because the shape of the leaf is beautiful. Home growers, ourselves included, usually harvest before that point. We cover both options below. And whichever way you grow it, the method is the same on soil, coco coir, and reusable silicone grow medium, so this one guide covers all three, the same way our broccoli microgreens guide does.

Quick Answer: How to Grow Kale Microgreens

The method below works for every kale variety. Spread 20 to 25 grams of kale seed on a 10x20 tray, mist it, and cover it with a second tray plus weight. After about 3 to 4 days, move the tray to blackout or straight into the light, then start bottom watering. Harvest in 8 to 12 days when the leaves are open and the stems are tall and sturdy. No pre-soak is needed, and the method is the same on soil, coco coir, and reusable silicone grow medium. Soil gets plain water. Coco coir and silicone get fertilizer water.

Tip: kale is easy to repeat, so we log every tray in Microgreen Tracker from the first seed. It tracks the seed date, medium, and harvest date, and it sends web push reminders for watering and harvest. We cover it in more detail near the end of this guide, and every new grower starts with a 7-day free trial.

Why Kale Is One of the Top Crops to Grow

If you are picking what to grow next, kale deserves a spot near the top of the list. Here is why we keep coming back to it.

• It is popular with real growers. At the time of writing, kale is the sixth most-grown crop among growers logging trays in Microgreen Tracker, our web app. That is a lot of people choosing it over dozens of other crops.
• It is forgiving. Kale is a beginner-friendly brassica that germinates evenly and handles small mistakes in watering and timing.
• It is fast. Most of our trays are ready in 8 to 10 days.
• It yields well. In our own grows, a single 10x20 tray has given us anywhere from about 177 grams on a smaller tray to well over 300 grams on a full one. See the results table below.
• It is easy to eat. The flavor is mild enough for people who say they do not like greens, and the texture is a real standout.
• It works on every medium. Soil, coco coir, and reusable silicone grow medium all grow it well.

Kale Microgreens Health Benefits

Kale is a brassica, the same plant family as broccoli, cabbage, and mustard, and brassicas are well known for vitamins C, K, and A and for plant compounds called glucosinolates. Microgreens as a group have been studied too. The University of Maryland and USDA found that many microgreen varieties contained 4 to 40 times more nutrients than their mature counterparts, which you can read in the University of Maryland's Mighty Microgreens summary. We are not making kale-specific nutrient claims beyond that, because the numbers vary by variety and growing conditions.

What we can say from our own kitchen is that kale microgreens are an easy way to eat more leafy greens. A big handful on top of tacos, eggs, or a rice bowl takes no effort. For the bigger picture, see why microgreens are so good for you, and if you are wondering about eating them fresh, read can you eat microgreens raw.

What Do Kale Microgreens Taste Like?

This is where kale surprised us. It does not taste like mature kale.

• Texture: kale has a thicker chew than most microgreens, but it stays soft and never turns woody. It is just a pleasant bite.
• Flavor: mild, with a slightly egg-like note and a super mild spicy undertone. Red kale leans closer to mustard.
• Scent: the smell when you harvest is incredible, and it is different from the other kale types. Red kale smells spicy and almost eggy, and you notice it the moment the knife goes through the tray.

Our Favorite Kale Varieties Right Now

If you want to start with the ones we grow most, these are our current favorites. The full list of varieties is just below.

Swipe the table left or right on a phone to see every column.

Every Kale Variety You Can Grow as a Microgreen

There are a lot of kale varieties sold for microgreens, and this guide works for all of them. Kale is one species, so the method does not change from one variety to the next: seed, weight, blackout, light, bottom water, harvest. What changes is the look, the height, and sometimes the seed size. Swipe the table left or right on a phone to see every column.

Names and availability vary by seed supplier, so the same variety can be sold under a few different names. We have only logged grows for the first four, so we are not making flavor or yield claims for the rest. If you try one, start with the seeding rate in this guide and adjust on your second tray. A variety with larger seed may want a little more weight, and a taller variety may want a shorter blackout or an earlier harvest. Our seed compatibility guide confirms kale works on the 1.2mm reusable silicone grow medium.

Choosing Kale Seed

Buy seed sold for microgreens from a supplier with good germination and food safety practices. Our default is True Leaf Market. We do not sell seed ourselves. Our microgreen seed hub explains where we buy, and our seed quality and food safety guide covers what to check on the label.

Supplies You Need

• 10x20 shallow trays, one with holes and one without (see our 10x20 tray guide)
• A growing medium: soil, coco coir, or a 10x20 reusable silicone grow medium
• Kale seed, 20 to 25 grams per 10x20 tray
• A misting sprayer for germination
• A second tray or blackout dome, plus weight
• Tray clip labelers to mark the crop and seed date
• Fertilizer for coco coir and silicone, such as Ocean Solution 2-0-3
• A grow light and a shelf (see our grow light setup hub)
• A sharp harvest knife and a scale

Soil, Coco Coir, or Reusable Silicone Grow Medium

Kale grows well on all three, and the timeline barely changes. What changes is the prep and what goes in the water.

• Soil: add about 6 cups of pre-moistened soil to a 10x20 tray and level it. We water with plain water, since soil already supplies what the seedlings need over a short grow.
• Coco coir: use about 6 cups of pre-moistened coco coir per 10x20 tray. Bottom water with fertilizer water starting the day the tray goes into the light.
• Reusable silicone grow medium: lay one flat on the mesh tray and mist it first so the seeds stick. We use the 1.2mm for kale. Bottom water with fertilizer water. Order the size that matches your tray (7x14, 10x10, or 10x20). Our reusable grow medium guide and seed compatibility guide cover sizes and care.

For fertilizer on coco coir and silicone, we use Ocean Solution 2-0-3 at 0.5 oz per gallon with water at pH 5.5 to 6.0. Our free fertilizer ratio guide and our post on the best nutrients and fertilizers for microgreens go deeper.

Kale Seeding Rates by Tray Size

Swipe the table left or right on a phone to see every column.

Log the seed amount and medium for every tray in Microgreen Tracker so you can compare what worked next time. Spread the seed evenly with no large clumps, because clumps trap moisture and invite mold. Our free tray-specific seeding guide lists rates for other crops.

Step-by-Step: Seed to Harvest

This is the schedule from our own grows. Yours may land anywhere between 8 and 12 days depending on variety, temperature, and light.

Day 1: Seed, Mist, and Weight

Prepare your medium, then spread the seed evenly. On silicone, mist first so the seeds stick. Mist the seed for 15 to 20 seconds until it is evenly wet, label the tray with a clip labeler, then cover with a second tray and add weight. Kale does not need a pre-soak. We covered why weight matters in why microgreens need weight during germination.

How much weight? In our own kale test (Vates Blue Scotch Curled on coco coir), we compared no cover, a paper towel, an empty tray on top, and an empty tray plus a 7 lb paver. The uncovered tray barely germinated by day 3, while the empty tray and the weighted tray did far better. The weight also pushed roots into the medium and helped the seed hulls come off. For a 10x20 we use about 5 lbs, and we have gone up to 14 lbs on a full tray.

Days 2 and 3: Seeds Crack Open and Roots Appear

By day 2, seeds crack open. Mist once or twice a day, then put the cover and weight back. By day 3 you will see the first root, called a radicle, with fine white root hairs. Those root hairs are normal and often get mistaken for mold. If you are unsure, see our mold prevention and identification guide.

Day 4: Blackout (Or Skip It)

Once most seeds have sprouted and you no longer see many seed shells on the canopy, remove the weight and flip the top tray into a blackout dome. Mist first so nothing dries out. Our guide on when to move from weight to blackout shows what to look for.

Set your blackout and harvest reminders in Microgreen Tracker so the day-4 and day-8 checkpoints do not slip. Kale grows aggressively, so blackout is flexible. In one lighting test we ran 3 days under weight with no blackout at all, and the kale still grew tall. With Purple Reign on soil, our notes say it only needed a few hours of blackout, and we plan to skip it next time.

Day 5: Into the Light and Start Bottom Watering

Uncover the tray and place it under the light. Pale yellow leaves coming out of blackout are normal and green up within a day. Start bottom watering with about 1 cup per 10x20 tray, with fertilizer water for coco coir and silicone and plain water for soil. Make sure the tray bottom touches the water.

Days 6 to 8: Bottom Water and Watch the Canopy

Bottom water about twice a day, topping off only what the medium absorbs. Roots reaching down into the reservoir is a good sign, and you can lift the tray to check.

Our complete watering guide explains how to read the tray. For light, we use 16 to 17 hours a day with the light 8 to 12 inches above the canopy. In a side-by-side kale test, Barrina T5 LEDs averaged 305 g per tray against 300 g for T5HO fluorescent, and Mandi preferred the fluorescent tray for slightly more flavor and crunch. Flavor was similar overall, and the LEDs cost less to run. More in Microgreen Lighting: Best Grow Lights After 7 Years of Testing.

Days 8 to 11: Harvest

Our kale is usually ready between day 8 and day 10, and slower methods run to day 11 or 12. Harvest when the leaves are open and the canopy is tall and even, just above the medium with a sharp knife, keeping roots and medium out of the bowl. Harvest before the tray gets so tall it starts falling over. A tray gets one harvest, so once it is harvested the tray is finished.

Harvest Early or Let the True Leaf Show

Kale gives you a choice. Most home growers, including us, harvest when the cotyledons are open and the canopy is tall and even, which is the soft, tender stage in our harvest log. If you wait a little longer, the true leaves begin to come through, and that is the stage many commercial microgreen farms aim for with kale on purpose, since the true leaf has a more pronounced and attractive shape. You can see the first sign of it in our Kratky grow around day 11.

• Harvest early for the softest bite and the most tender texture. This is what we usually do.
• Let the true leaf show for a fuller, more decorative look on the plate. Keep an eye on height, because a tall tray can flop over, and kale grows fast.

Either way, harvest just above the medium, and log the harvest day in Microgreen Tracker so you can compare how each timing turned out.

For tools and technique, see what works best for harvesting microgreens and our harvesting tools list.

What Our Own Kale Trays Produced

These are real trays from our harvest log, the same kind of log you can keep for your own grows in Microgreen Tracker. They are our results in our grow space, not promises. Swipe the table left or right to see everything.

Two of our video grows landed in the same range. A 9-day Red Russian grow on reusable silicone grow medium gave us 213.5 grams from 20 grams of seed, and a Red Russian Kratky grow gave us 370 grams in 11 days from 25 grams. Purple Reign has been our heaviest crop, and it grows tall, so watch it as harvest day gets close.

The Kratky Method for Kale

Kale is also a great fit for the Kratky method, where a 2 inch deep reservoir tray sits under a mesh tray and the roots hang over the water. We added 14 cups of fertilizer water (0.5 oz per gallon, pH 5.5 to 6.0) on day 5, left about an inch of breathing room for the roots, and did a root drip test to confirm they touched the water. After that the reservoir lasted days with no extra watering. We sell the Kratky tray kit, and our Kratky method guide covers the full setup.

Watch Our Kale Grows

We have filmed kale grows from every angle: a full seed-to-harvest on reusable silicone grow medium, Kratky, weight and lighting tests, and a medium comparison. Here is the full silicone grow first, then more kale videos from our channel.

More walk-throughs are in our video library.

Troubleshooting Kale Microgreens

Most kale problems come down to water, airflow, and seeding density. Fix those three and almost everything else sorts itself out. Our troubleshooting hub collects every guide in one place.

Is it mold or root hairs?

Root hairs are fine white fuzz at the base of the seedlings in the first few days, and they often disappear when you mist. Mold looks patchy, spreads across the leaves or stems, and may smell musty. If you are unsure, mist the spot and check again in a few hours. If it is still there, treat it as mold. Fixes: seed less densely next time, add airflow with a small fan, and stop watering more than the tray absorbs. See our mold prevention and identification guide for the full breakdown.

Why are there wet spots in my tray?

Dense seeding can hold water in patches. When we saw this on a couple of hydroponic mediums in our older medium test, Mandi's tip was to seed a little thinner. Three things solve it for us:

• Seed less densely. Spread the seed evenly with no clumps so air can move through the canopy.
• Control the humidity. A dehumidifier is a huge help in a grow space, and our humidity and microgreens guide explains how to manage it.
• Do not over-water. Check the reservoir before you add more, and skip a watering if there is still water in the bottom tray.

Why is part of my tray not germinating?

Uneven moisture or a weight that does not sit flat is the usual reason. In one of our reusable silicone grow medium grows, one area did not germinate. Fixes: mist until the whole surface is evenly wet, spread the seed evenly, make sure the weight sits level on the tray, and use fresh seed. If a bare patch shows up on day 3, mist it and put the weight back for another day.

Why are the seed hulls still stuck on?

Seed hulls that stay on usually mean the seed was not held against the medium. Weight during germination pushes the roots down and helps the hulls come off, which is what we saw in our weight test. Make sure the weight is on from day 1 and covers the whole tray. A light mist on the canopy during the first days also helps loosen them.

Why are my kale microgreens short?

Common causes are too much light too early, water quality, cool temperatures, missing fertilizer on coco coir or silicone, or heavy seeding. Fixes: keep the tray covered until the roots are down, check your fertilizer water on coco coir and silicone, and thin the seeding on the next tray. See why microgreens stay short for the full list.

Why did my tray get so tall?

Kale, and Purple Reign in particular, grows fast. If a tray is getting tall enough to flop over, shorten or skip blackout and harvest a day earlier. If it is stretching toward the light, lower the light closer to the canopy. Our common growing mistakes guide covers more.

Fungus gnats

Fungus gnats are most common on soil and coco coir that stay too wet. Let the surface dry between waterings and do not over-water. See managing fungus gnats indoors.

When a tray does go wrong, the notes you took are the fastest way to find out why. We keep ours in Microgreen Tracker: the seed amount, the medium, how much water went in, and what we changed, so the next tray starts with the fix instead of a guess.

After Harvest: Storage and Cleanup

Store harvested kale dry in a container lined with paper towel in the refrigerator. One tray from our Kratky grow gave us about two weeks of greens for the two of us. Details are in how to store microgreens.

For reusable silicone grow medium, remove leftover roots with a medium scraper, then hand wash and follow our cleaning and sanitizing guide. For soil or coco coir, see what to do with the used grow medium. Wondering about a second harvest? See will microgreens regrow after harvesting.

Ways to Use Kale Microgreens

• Piled on salads for depth and color
• On chicken tacos, rice dishes, and eggs
• In burgers, wraps, and sandwiches
• On pizza after it comes out of the oven
• Blended with other brassicas, like the red cabbage, kale, and purple sprouting broccoli blend below

More ideas are in our microgreen recipes hub.

Frequently Asked Questions

How long does it take to grow kale microgreens?

Most trays are ready in 8 to 12 days. Ours are usually ready on day 8 to 10.

What do kale microgreens taste like?

Mild, with a slightly egg-like flavor and a very mild spicy undertone. They have a thicker chew than most microgreens that stays soft and never woody. Red kale leans closer to mustard.

When should I harvest kale microgreens?

Most home growers harvest at the cotyledon stage, usually day 8 to 10 for us. Many commercial farms let kale grow until the true leaves show because of the leaf shape. Both work, so it comes down to the look and texture you want.

Do kale microgreens need to be soaked?

No. Mist the seed and add weight.

How much kale seed do I need for a 10x20 tray?

20 to 25 grams. We use 25 grams in most recent grows.

Can I grow kale microgreens on soil, coco coir, and reusable silicone grow medium?

Yes. The method is the same on all three.

Does this guide work for every kale variety?

Yes. Kale is one species, so the same method works for every variety. Start with 20 to 25 grams on a 10x20 and adjust on your second tray. See the full variety list above.

Which kale variety should I grow first?

Red kale (Red Russian) is a great start for the color and flavor. Lacinato is our pick for height and chew, and Purple Reign for the heaviest harvest.

Will kale microgreens grow back after I harvest?

No. A tray gets one harvest.

Are kale microgreens good for beginners?

Yes. Our beginner's guide to growing microgreens and the Beginner's Guide PDF are good places to start.

Keep Track of Your Kale Grows With Microgreen Tracker

Kale is a crop worth repeating, and repeating it well comes down to remembering what you did. We log our trays in Microgreen Tracker, our web app for tracking microgreens, and kale is one of the most-grown crops among the growers who use it. For a kale tray, we log the seed date, medium, seed amount, and harvest date, so the next tray starts from the last one's notes instead of memory.

Here is how it fits a kale grow:

• Log the tray and harvest date: save the seed date and see where the tray is in its grow, such as a Purple Reign tray on soil at day 9 of 11.
• Reminders: web push reminders for watering and harvest help with bottom watering days and harvest day.
• Water and cost: the tray screen shows the water used and estimated cost for each tray.
• Tray notes: if a tray runs tall or comes up short, look back at the seed, medium, and what you changed.

It is a responsive web app that works in any phone or desktop browser and installs to your home screen with no app store. Every new grower starts with a 7-day free trial of the complete app. To see how it works, read Meet the Microgreen Tracker or follow the walk-through for planting your first tray, then Start My Free 7-Day Trial.

Final Thoughts

Kale microgreens are fast, forgiving, and a little bit special thanks to that soft, chewy bite and an unforgettable scent. Once you have the rhythm of seed, weight, blackout, light, and bottom water, you can grow any kale variety on any medium. New to all of this? Start at our Learn hub.

Related Blogs You Might Enjoy

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• Types of Microgreens
• How Many Types of Microgreens Are There?
• Best Microgreens to Grow in the Fall
• Growing Microgreens in Winter
• How to Grow Microgreens: A Complete Step-by-Step Guide
• Tracking Microgreen Grow Data
• Coco Coir vs. Reusable Grow Medium Case Study

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The results and opinions shared in this post are based on our own first-hand testing in our specific, controlled grow space. Any mention of a brand or product reflects our own experience, not a sponsored or definitive review. Your climate, water, seed, and setup are different from ours, so your results can vary. We always encourage you to run your own experiments and see what works best for you.

The information in this blog is for educational purposes only and is not intended as medical or nutritional advice. Always consult a qualified healthcare provider for personal health guidance.

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Updated: November 10, 2026

Happy growing!