Mustard greens are part of the Brassica juncea L. family, together with collards, cauliflower, broccoli, and kale.
Also called vegetable mustard, brown mustard, or Chinese mustard, their bitter and spicy flavor make them a good addition to salads, smoothies, and stews.
If you want them in your garden, you’ll be thrilled to learn that they are easy to grow.
When to harvest mustard greens? You can harvest mustard greens early when they are about 20 to 30 days old. Wait six weeks after sowing if you want to enjoy their fully mature velvety leaves at their most flavorful state.
How Do You Know When Your Mustard Greens Are Ready to Harvest?
If it’s your first time growing mustard leaves, you won’t have to wait long to enjoy the fruits (or leaves?) of your labor.
Here’s how you can tell if they are ready to harvest:
Days of Maturity
The best way to tell if your mustard greens are ready for picking is by referring to their days of maturity.
As a cool-season leaf crop, you plant the seeds of mustard greens around early spring to late summer. They may tolerate light frost, but they aren’t as hardy as kale or collards.
Given the proper growing conditions, you can expect the seeds to germinate in about four to seven days.
These plants are fast growers and will grow quickly when you give them a steady supply of water. They will also benefit from regular feedings using water-soluble plant food.
In approximately 10 days after sowing the seeds, you can start picking some as microgreens.
About 10 to 20 days after, you can harvest them as baby mustard greens. They will be fully mature after 40 to 50 days after sowing.
Size of the Leaves
You can start picking mustard greens when they measure three to four inches. Note that they are still young and tender, so you might not get the full flavor yet.
If you’re looking to harvest baby mustard greens, wait until the leaves are about six to eight inches long.
For fully mature leaves, expect them to measure around 15 to 18 inches.
What Happens if You Don’t Harvest Mustard Greens?
Mustard greens will get increasingly bitter and tougher as they stay on the plant for longer than they should.
As mentioned, you can begin harvesting as early as four weeks after planting. In fact, it would be best to pick individual leaves regularly to encourage the plant to produce more.
That said, others wait until they are fully mature and harvest everything at once.
Once the weather begins warming up in summer, mustard plants will shift their energy to grow flower stalks and produce yellow blooms.
Called bolting, this stage in the plant’s life means it is done producing leaves. You will find that the leaves will have become too bitter to eat at this point.
The plant will not survive afterward, so you might want to harvest the flowers and put them in a vase instead.
How To Harvest Mustard Greens?
Even if you’re new to home gardening, growing mustard greens is quick and easy. They aren’t as demanding as other crops and will be ready for harvest sooner.
To give you an idea of what to expect, here are steps to harvesting mustard greens:
Step 1: Pick individual leaves or cut the entire plant.
Depending on your needs, you can choose to harvest only the outer leaves from time and time and leave the center to grow and mature more.
Others prefer cutting everything down to about four inches from the base and waiting for it to re-grow.
Step 2: Harvest regularly.
From the leaves are three to four inches long until they are fully grown, continue harvesting mustard greens regularly.
Make sure you complete the harvest before temperatures go too high, or the leaves will turn tough and bitter.
It’s also not a good idea to allow the plants to go to seed unless you want to harvest them for planting next season.
A little over a week after the seeds have produced true leaves, you can start harvesting mustard greens as microgreens.
Carefully uproot the young seedlings and then wash them under running water to remove any debris.
You can eat microgreens as is, mix them into salads, or use them as toppings for pizza or soups.
Picking Baby Mustard Greens
Baby mustard greens are mild-flavored, so they can be eaten raw in salads or sandwiches.
That said, it might be an acquired taste for some, so sample a couple of young leaves before picking many.
To harvest baby leaves, make sure you use sterile scissors and cut the outer leaves down to 0.5 inches from the ground.
Again, you can also cut the entire plant and leave the stub to grow a new set of leaves.
When it comes time to harvest fully grown leaves, we’re sure you’d be more confident because you already know what to do.
Harvesting Mature Mustard Greens
For harvesting mature mustard greens, make sure you only cut the larger outer leaves right down to the base.
The inner leaves will continue to grow, giving you enough supply throughout the season.
Step 3: Continue caring for the plants.
What we like about growing mustard greens is that they will continue producing leaves until the end of their growing season.
Even better, you can extend the harvest season by planting them in batches every few weeks.
It’s also a good idea to plant them where they aren’t exposed to too much direct sunlight that could easily scorch the leaves.
Adding mulch around late spring is another good trick to help the ground retain moisture, which mustard green plants love.
Step 4: Harvest the seeds.
If you plan on growing mustard greens again next year, you can allow a few of the plants to bolt and produce flowers.
Over time, the flowers will mature and produce seed pods. You can then gather the seeds either by cutting a couple of branches or entire plants.
Place your harvest in containers or drop cloths to prevent seed loss.
Mustard seeds can also be turned into a spice.
Should You Wash Mustard Greens After Harvesting?
You already know to wash microgreens before eating raw or cooking, but is the same true for baby leaves and fully grown mustard greens?
Certainly! And it’s fairly straightforward to do, too.
To remove sand and dirt, make sure you wash your harvest in a large bowl filled with lukewarm water.
After that, cut and throw away the stems, as well as any and all discolored parts. You can then braise, steam, sauté, or stir-fry.
Storing Freshly Harvested Mustard Greens
There are plenty of ways to enjoy mustard greens, but in case you have an abundant harvest, you can store them for future use.
Dry the leaves after washing and then place them in a sealed plastic bag. Put the bag in the fridge and use the leaves within three to four days.
If you want to store them longer, you can also freeze the leaves after washing them.
Before you do, blanch them first by dipping them in a pot of boiling water for approximately three minutes.
After enough time has passed, strain and transfer the leaves immediately into a bowl of ice water to cool them down.
Drain the water and then put the leaves in freezer bags. Remove as much air from the bag as possible before placing it in the freezer.
Can You Eat Mustard Greens Immediately After Harvesting?
Like other leafy greens, you don’t need to wait and ripen them off after harvesting. In fact, you can cook them or add them to your dish as soon as you wash them clean.
These tasty leaves are common in Mediterranean and Asian dishes and pair well with sausages, lamb, and pork.
You might also enjoy their flavor when added to creamy sauces, cheeses, and vinegar dips.
A lot of the time, mustard greens are cooked and seasoned with equally interesting flavors like garlic, dill, fennel, cilantro, and cumin.
This low-calorie yet high-fiber greens contain all the good vitamins and minerals you want in your diet. These include vitamins K and C, which help strengthen the immune system.
They also have a good amount of antioxidants and different kinds of B vitamins.
That said, those with problems with their kidneys might want to think twice about eating them regularly.
Mustard leaves have oxalates, which can increase a person’s risk of developing kidney stones.
Depending on where you live, you can grow mustard greens in your spring or fall garden.
They may not survive freezing temperatures, but they love the cold and will produce sweeter leaves in such conditions.
Besides being easy to care for, these plants are delicious and pack essential vitamins and minerals.
They are also a good companion plant for fall flowers like pansies and jasmine, as well as vegetables like snap peas and English peas.
Lastly, you can harvest them in several ways: as microgreens, as baby leaves, or as fully grown leaves.
This means you can enjoy its distinct flavor from 10 days after planting the seeds up until the end of the harvest season.