By Erin Marissa Russell
Mustard greens are a member of the Brassica family of plants and are sometimes referred to as simply mustard or as brown mustard, Chinese mustard, Indian mustard, leaf mustard, mustard spinach,or white mustard. This cool-season vegetable is a popular choice for home gardeners because it’s easy to care for and matures quickly, with maturation periods ranging from four to six weeks.
Although in cuisine greens as a dish are most commonly associated with the American south, mustard greens can be grown by gardeners in the central and northern regions of the United States as well during the part of the growing season with cool weather in their regions. The mustard greens plant can be grown with success in USDA Hardiness Zones 6 through 11 as a springtime crop, and it can be grown in fall as well by those in zones 8 through 11.
Mustard greens are annual plants that reach heights between half a foot and two feet tall and measure one or two feet wide when mature. At the end of the growing season, like many other vegetables, mustard green plants will bolt, or go to seed.
Bolting is a natural part of the plant’s growth cycle and must eventually happen— though bolting can be delayed for a time, it cannot be avoided completely. Once the season begins to change as days get longer and hotter so that foliage production must come to an end, plants turn their attention to reproduction. Your mustard plants might also bolt when it isn’t yet time by the calendar as a response to stress of some kind.
When mustard greens bolt, they send up a flowering stalk from the center of the plant that will first open into a yellow blossom, then begin to produce seeds. This flowering stalk will leach energy and nutrients from the rest of the plant so forcefully that just a short time after the plant begins to bolt, the greens will become unappetizingly bitter, though not as bitter as bolted lettuce. So if you notice that your greens have started to go to seed just as the bolting process is beginning, it’s fine to still go ahead and harvest and eat the greens.
However, if you don’t notice right away, the greens won’t be good to eat any more, so you might as well leave the plant in the garden so it can produce seeds for you to collect so you can save them to plant another crop next year. Before you decide to do this, you should know that only heirloom varieties of mustard greens will produce a next season of plants that are true to type.
Other mustard green varieties can still be allowed to seed and planted later on, but plants in the new generation will vary slightly from the plants the seeds were collected from. To collect mustard green seeds, allow the seed pods to mature on the plants until they turn brown. Make sure to collect the pods before they open, unless you want to permit your mustard plants to sow their own seeds for next season.
You can also plant a new batch of mustard greens every two weeks to enjoy a continuous supply of mustard greens throughout the growing season. The dark green leaves have a distinctly spicy, bitter flavor. Varieties are available with red or purple-hued leaves as well.
Nutritionally, mustard greens are low in calories but pack plenty of fiber and valuable micronutrients. Just one cup of mustard greens, measured raw and chopped, offers 2 grams of fiber, 2 grams of protein, 6% of the daily value of vitamin B6 (pyridoxine), 8% of the daily value of vitamin E, 9% of the daily value of sugar, 10% of the daily value of copper, 44% of the daily value of vitamin C, and 120% of the daily value of vitamin K.
These mega-healthy greens also provide four or five percent of your daily value of the following: calcium, iron, potassium, riboflavin (also called vitamin B2), magnesium, and thiamine (sometimes referred to as vitamin B1). Cooking your cup of greens increases their nutritional value, making the measurements of vitamin A’s percent of daily value 96%, vitamin C’s percent of daily value to 22.7%, and vitamin K’s nutritional value 690%. (No, that’s not a typo—six hundred and ninety percent. .) However, cooked mustard doesn’t offer as much vitamin C or vitamin E as raw mustard greens do.
Varieties of Mustard Greens
There are four main categories of mustard green plants, with various plant species in each category. The major types for gardeners to choose from include Brassica hirta or yellow mustard, the best known type of mustard that most seeds come from; Brassica nigra or black mustard, which packs a spicy punch but is widely considered less tasty than yellow mustard; Brassica alba or white mustard, which has the mildest taste and is a favorite for pickling; and Brassica juncea, which is also called Oriental mustard or brown mustard and is known for its good taste.
Mustard plants may be curly leaf varieties or smooth leaf mustard (also called mustard spinach or tendergreen. Plants of the curly leaf varieties are likely to take longer to clean because the ruffles in their foliage tend to hold dirt and grit from the garden. Curly leaf mustard greens also have a longer growth period than the smooth leaf types, which perform better than those with curly leaves in hot, dry climates.
Cook’s Custom Mix: This multipack of mustard greens combines the varieties Florida broad leaf, mizuna, Osaka purple, and Red Giant Indian.
Florida broadleaf: The most popular variety of mustard greens for growing in gardens, Florida broadleaf is an heirloom with large, broad, flat leaves that have a sawtooth edge and savory flavor. 45 days.
Garnet giant: Garnet giant mustard offers the darkest baby leaves available, with burgundy foliage that turns green when cooked. However, it can be quick to bolt. 45 days.
Green wave: Frilly green wave mustard plants are slow to bolt and withstand heat well but are tolerant of cold. Known for high yields and spicy flavor. 50 days.
Old Fashion Ragged Edge: This southern heirloom with ruffly, narrow leaves is known for being considered best in flavor, though it can be quick to bolt. 42 days.
Red giant: Red giant mustard has burgundy textured leaves with green midribs and is almost as pretty as it is tasty. 40 days.
Savanna: This quickly growing mustard green has tender, sweet leaves. 20 days.
Southern giant curled: This curly mustard green variety produces large plants that resist cold well and are slow to bolt. Does well when frozen or canned. 50 to 70 days.
Tatsoi: This Asian mustard variety has bright, mild flavor and handles the cold so well you can harvest it from under snow cover. 45-55 days.
Tendergreen (mustard spinach): This heirloom variety has mild flavor and is known for resisting heat and drought. 35-40 days.
Growing Conditions for Mustard Greens
Prepare the soil where mustard plants will grow with your choice of either a two-inch layer of compost mixed down into the top six to 12 inches of the ground or a 10-10-10 fertilizer blend, applied at a rate of 14 cups per 10-foot row of mustard greens.
If you want to take advantage of companion gardening, whether it’s to save on space or simply to take advantage of the benefits, plant mustard greens next to beets, carrots, celery, cucumber, dill, lettuce, mint, nasturtium, onions, rosemary, thyme, tansy. Your mustard green plants should be kept well clear of spaces where strawberries, sunflowers, or beans are growing.
How to Plant Mustard Greens
For a springtime mustard crop, sow your seeds two to four weeks before the last expected frost of the spring. If you’re not sure what your last frost date is, you can learn how to find it out by clicking here. If you want to raise mustard greens as part of the fall garden, start your plants at the end of summer or beginning of fall. If your greens end up having to weather a light frost, their flavor will actually improve to be sweeter.
Of course, you also have the option of purchasing young mustard plants at the nursery or garden center and transplanting them into your garden when the time is right, but most gardeners find growing mustard greens from seed so easy that they go with that method.
When you’re ready to plant your mustard greens, sift through the soil in the spot you’ve picked out for them to remove any clods, clumps, stones, or twigs. Then work or till the soil to loosen it, raking the surface when you’re done.
Your mustard green plants can be laid out in either of two ways. Mustard can be grown in rows, or mustard plants can be clustered in their own garden bed. If you grow mustard in rows, position the rows with two feet of space between them. You’ll thin the seedlings later to leave 48 inches between each plant.
If you set up your mustard greens in a garden bed, simply sprinkle the seeds over the area allotted to mustard greens. Whichever option you choose, top your freshly planted seeds with a fine layer of soil, and mist the ground to moisten it immediately after planting. Check in often to ensure the soil stays moist at all times until your mustard green seeds have germinated.
Care for Mustard Greens
In order for mustard green plants to thrive, gardeners will have to supply them with an even and continuous water supply all season long. As with other plants, mustard greens should be watered from the base of the plant to prevent splashing the foliage. Gardeners use this technique to water their plants because wet foliage can contribute to plant problems like fungal diseases or root rot.
When your plants are established, consider adding a layer of mulch over the surface of the soil where your mustard greens are growing. Mulching will both improve the soil’s ability to retain water and prevent weeds from taking hold in your mustard greens bed.
Once your mustard plants are between three and four weeks old, feed them by providing a 10-10-10 fertilizer blend at the same rate as when you amended the soil before planting your greens. Simply apply the fertilizer around the base of your mustard plants, and if it’s a granular type, water the fertilizer in just afterward. Alternatively, you may wish to use a fish emulsion or seaweed fertilizer instead. Simply follow the manufacturer instructions regarding dosage and frequency.
Garden Pests and Diseases of Mustard Greens
Mustard plants don’t usually fall victim to the diseases that can plague other members of the Brassica family]. That means gardeners of mustard greens only really need to be vigilant against the pest insects we’ve listed here.
Aphids: There are lots of different kinds of aphids out there that vary in color and size, but all of them are tiny, and all of them tend to hang out on the underside of the leaves of plants they’re victimizing. Aphids suck the liquid out of leaves, resulting in crumpled, withered, or distorted foliage. You can fight off aphids by applying a homemade spray of one gallon of warm water mixed with four or five drops of dish soap and a tablespoon of neem oil.
Cabbage worms: You may detect cabbage worms on your mustard green plants by noticing either their bullet-shaped yellow or orange eggs that always appear alone, the velvety green caterpillars, or white cabbage butterflies. You may also see yellow-green pupae attached to plants or ragged holes where foliage is missing because the caterpillars have dined in your garden. Floating row covers work well as a preventive measure, and you should pick off caterpillars by hand and deposit in a pail of soapy water, then treat the garden with botanical Bt.
Flea beetles: If you don’t detect the presence of flea beetles by spotting the small black bugs, you may notice irregularly shaped holes where they’ve fed. Fight back with floating row covers or Microctonus vittatae, a braconid wasp that preys on flea beetles.
How to Harvest Mustard Greens
You can begin harvesting your mustard greens once the leaves have grown to reach three inches. Mustard greens that grow larger than three inches long should always be consumed cooked instead of raw. Mustard greens taste best when the foliage is still young and the temperature has not yet begun to get warm.
Like almost all varieties of greens, mustard is a “cut and come again” vegetable, which means that when you’re ready to cook some greens, you can simply trim the leaves you will use off the plant, choosing the outer leaves at the base. The mustard plant will continue to produce new leaves, replacing those you clipped off so there will be more to harvest next time you need to gather some greens from the garden.
Mustard greens are most commonly eaten braised in a flavorful broth ( often with bacon), as they’re prepared in the soul food tradition, but mustard can also be boiled, steamed, stir-fried, or picked young and enjoyed raw in a salad. Chinese and Japanese cooking feature pickled mustard greens, called takana in both cultures.