How to Plant, Grow, and Care For Swiss Chard
Swiss chard is often a favorite crop to grow for many gardeners, due to its ease of care, and many different uses. But to grow it successfully, you'll need to make sure that you meet the growth needs for this useful plant. In this article, gardening expert Logan Hailey examines how to plant, grow, and care for Swiss Chard, also known as Rainbow Chard.
Whether spring or fall, it’s never a bad time to plant vigorous, low-maintenance rainbow vegetables in the garden! Rainbow chard or Swiss chard (Beta vulgaris) is a leafy green with vibrant, colorful stems.
Chard is an ultra nutritious and easy-to-grow cousin of beets and spinach, and it comes in many different varieties. The leaves have an earthy, mild taste and the gorgeous technicolor stems visually resemble rhubarb or celery, but taste more like a mild beet. Swiss chard is one of the healthiest vegetables you can eat, with over 300% of your daily dose of vitamin K and more than 20% of recommended vitamin C.
Beyond its health benefits, this vegetable is the gift that keeps on giving in the garden. You can plant chard once a year and harvest rainbow greens all season long. Growing chard is fairly simple and perfect for beginner gardeners seeking to add some color to their harvests.
Swiss Chard Plant Overview
Plant Type Biennial Grown as Annual
Species Beta vulgaris
Hardiness Zone USDA 3-10
Season Spring and Fall
Plant Height 1-3 feet
Fertility Needs Light to Moderate
Plant With Brassicas, Cool Weather Greens, Scallions
Don’t Plant With Corn, Cucurbits, Spinach, Potatoes
Soil Type Fertile, Well-draining
Plant Spacing 1-2” for baby leaf, 4-6” for full size and 12-18” between rows
Watering Needs Moderate
Sun Exposure Full to Partial Shade
Days to Maturity 50-65 days
Pests Spinach Leafminer, Wildlife
Diseases Damping Off, Downy Mildew
Rainbow chard is a member of the Chenopodiaceae family, along with beets, spinach, quinoa, and lambsquarter. Beta vulgaris is technically a beet, which you will notice from its roots.
Chard has been bred for lush greenery with different colored stems rather than the deep-colored beetroot bulbs we are familiar with. You will notice that chard greens are significantly more tender and less bitter than beet greens thanks to these traditional breeding efforts.
Origins in Mediterranean, Not Switzerland
Contrary to its name, Swiss chard is not from Switzerland. It originated from wild beets that grew in Sicily, Italy. It has been used in Mediterranean cuisine since ancient Greece and has also been called “spinach beet,” “stem chard,” and “Roman kale.” It is also often called “Swiss chard” because it was given the scientific name Beta vulgaris by a Swiss botanist in the 19th century.
Chard remains extremely popular in Mediterranean food because of its neutral flavor, versatile uses, and impressive nutrient profile. It’s also traditionally used in fresh salads, couscous, orzo salads, soups, frittata, and pastas.
Supergreen Nutrients and Anticancer Properties
Rainbow chard is rich in vitamins and minerals. It is a nutritional powerhouse “supergreen” just like kale or spinach. It has an abundance of Vitamins A, C, E, and K, as well as calcium, copper, magnesium, iron, potassium, and manganese. Just one cup of cooked chard covers your recommended daily intake of vitamin A and K! It is also very low in calories and even has a bit of protein (about 3g per cup).
This vegetable has a flavonoid called syringic acid which could be beneficial for lowering blood sugar levels. It is also full of antioxidants like beta-carotene that help protect cells from free radical damage. A diet high in rainbow chard has been shown to lower the risk of lung cancer and even inhibit cancer cell growth in pancreatic cancer patients.
It’s important to also enjoy the stems (hint: chop them up tiny and use them like rainbow confetti on top of pizza, scrambles, or sautees). The stems are an incredible source of fiber and anti-inflammatory properties.
Biennial or Annual?
This plant is technically a biennial that is grown as an annual. Biennial means it takes two years to complete its life cycle: vegetative (leaf and root) growth in the first year and reproductive (flowers and seeds) growth in the second year.
However, most farmers and gardeners grow it as an annual and re-plant every season. In zones 7-10, chard can overwinter and sometimes grow as a perennial if it is continuously harvested and any flower stalks are cut back.
Propagation and Planting
If you want a bountiful crop, making sure you hit the right propagation and planting requirements is absolutely vital with swiss chard. Let’s take a look at the best ways to plant this vegetable, as well as what you can expect.
When to Plant
In northern climates, it is best to plant in early spring or midsummer. It can be transplanted out a few weeks before the last frost, as long as hard frosts have passed.
Use a soil thermometer to check the soil temperature before planting. Chard is cold hardy and will germinate in soil temperatures as low as 40°F, however, if you plant too early in the spring some varieties may bolt (go to seed) when exposed to long periods of freezing temperatures.
Seedlings tolerate light frosts (30-32°F) and mature plants can withstand moderate frosts (20-25°F). In zones 6 or warmer, this plant will overwinter and can be planted almost any time of year.
In the south, chard is typically sown in late summer or fall and harvested throughout winter and spring. Cool mild weather is ideal, but it will tolerate some heat.
Succession planting means preparing for multiple sowings of a given crop in order to maintain a continuous supply throughout your growing season.
When planning your garden, consider planting one or two successions of rainbow chard, beginning in early spring and potentially planting another in late summer or early fall. While you can harvest leaves from a chard plant continuously throughout the season, older plants may get more bitter or tough leaves as time goes on.
Prepare Soil for Planting
Chard needs well-drained, loose soil high in organic matter. It is best to add 1-3” deep of compost to your garden beds for planting. This plant prefers a soil pH between 6.0 and 7.0. It also prefers consistent moisture throughout the growing season, so be sure to use irrigation in your gardening patch if needed. Mulching around chard will conserve moisture and keep your plants even happier.
How to Direct Seed Chard
To direct seed chard, begin with shallow furrows about 18-24” apart. Chard seeds should be sown ½” deep and lightly covered with soil. Keep moist until germination. Seeds germinate best in soil temperatures around 86°F but will come up in soils between 40 and 100°F.
Like beets, chard seeds are also “seed clusters.” This means each seed holds multiple ovaries. As many as 1 to 6 seedlings could sprout from a single seed, so thinning is essential. When seedlings reach a couple of inches tall, thin them to 6-12” apart using needle-nose pruners. Choose the strongest plant to leave behind and be sure not to disturb it when thinning out the sister seedlings.
How to Transplant Chard
Unlike other root crops, the beetroot bulb of chard doesn’t mind transplanting, and in fact, performs best when transplanted. This will also give you a head start in early spring. Start seeds inside about 5 to 6 weeks before the last frost.
Sow ½” deep with 1-2 seeds per cell in 72-cell flats or 6-packs. Thin to 1 seedling per cell.
When their roots have filled their cell and they have a couple of sets of true leaves, you can plant them into the garden using a hori hori or hand trowel. Lay out a tape measure and make a hole about the dimensions of your seedlings. Plant about 6-12” apart in rows 12-18” apart.
Gently backfill, being sure not to bury the stem. The soil level should remain in line with the original plant. Chard should never be planted too deep because it is subject to damping off or rotting from the base in excess moisture conditions.
Rainbow chard is best spaced about 4-6” apart in rows 12-18” apart for full-size leaves.
Baby leaf production can be sown as close as 1-2 seeds per inch with rows 2” apart. Planting chard too dense will lead to stunted growth and overcrowding, as well as greater disease risk.
Companion planting improves the biodiversity of your garden while repelling pests and helping to prevent plant disease. Rainbow chard grows well alongside tomatoes, Brassicas (cabbage family plants), and Alliums (onion family plants). You can also interplant radish, lettuce, and celery alongside as long as they are given enough space to thrive.
Avoid planting chard near potatoes, cucumbers, corn, cantaloupe, or other melons. These plants may overgrow chard, compete for nutrients and water, or shade out the chard plants. It is best to separate chard from its cousins beets and spinach to maintain diversity and avoid attracting similar pests or pathogens.
Chard is typically planted in colorful mixes to yield rainbow bunches. You can buy multiple varieties of seeds by the color or in pre-mixed rainbow varieties such as ‘Bright Lights’.
The classic rainbow chard, ‘Bright Lights’ is a colorful blend known as the gold standard for chard plantings. The leaves are slightly savoyed (curly) and glossy, with stems of gold, pink, orange, purple, and red. There are bright and pastel colorations mixed into this population. ‘Bright Lights’ has the most bolt resistance, vigor, and growth consistency of any chard I’ve grown. It is, however, less frost-hardy than other varieties.
This organic strain has dark green, red-veined leaves and stems that range from candy-apple red to reddish-bronze. It has some bolt resistance but is best used in summer plantings because it may go to seed during prolonged cold night temperatures.
A new hybrid of super clean, lofty, vibrant leaves! ‘Charbell’ was originally bred for baby leaf production, but it is great when harvested at full size as well. It stands very upright, which prevents mud splash in winter or wetter climates. It is extremely bolt resistant for summer production and can be grown as close as 4-6” between plants.
Pelleted vs. Non-Pelleted Seeds
Some chard seeds come with a pellet covering. Typically made of kaolin clay, seed pelleting is an inert coating that makes seeds more uniform for sowing. It can be easier to singulate seeds and clearly see them in the soil while planting. Be sure that your pellet is an untreated organic-compliant coating. Pelleted seed needs to be kept continuously moist throughout germination in order to thoroughly dissolve the coating.
Non-pelleted chard seed looks like a standard knobby beet seed and is fairly easy to handle. Because of the larger seed size, it can be easier for children and elderly gardeners to seed by hand. Pelleted seed is especially beginner-friendly.
Swiss Chard Care
Rainbow chard is remarkably low-maintenance and not very finicky. It can take some neglect, but will definitely produce the lushest healthy growth in these conditions:
Chard prefers consistent moisture throughout its growing cycle. The larger plants can be thirsty in hot weather and should have easy access to irrigation. It is best to use soaker hoses, drip irrigation, or small sprinklers for watering. Chard prefers about 1 to 1.5” of water per week if there is no rain.
Check soil moisture 1-2 times per week by sticking your finger in the soil. If it comes out dry, you need to water. If it comes out with moderate soil sticking to your finger, this is an ideal moisture. The soil should never be so soggy that it feels muddy or waterlogged, as this could lead to root rot.
Soil and Fertility
Like most garden vegetables, rainbow chard loves rich, deep, and fertile soil with an alkaline pH between 6.0 and 7.0. The best way to attain these conditions is with no-till garden methods, high-quality organic compost, and mulching.
However, this plant is pretty hardy. It will tolerate poor soils but may not grow as quickly. If your soil is lacking in fertility or organic matter, consider spreading a small amount of blood meal (12-0-0) or feather meal (12-0-0) around the base of plants around 2 weeks after planting.
Chard also enjoys a diluted helping of fish emulsion once or twice per season. These are organically approved fertilizers that will nurture soil biology while boosting leaf growth. Avoid over-fertilizing as this could lead to leaf burn or stunting.
Chard performs well with organic mulches like straw or chopped leaf mulch. Mulching will help retain moisture and keep weeds under control. It can be applied 1-3” thick, leaving a bit of air space around the base of each plant to avoid creating slug habitat or root rot.
Like its cousin spinach, chard really enjoys the cool weather of spring and fall. If given time to mature, rainbow chard can tolerate some hard frosts (15° to 20°F). Seedlings are more sensitive and should be protected with a floating row cover.
Chard prefers to be grown in slight shade, or full sun. Avoid planting in areas of the garden that get less than 6 hours of sunlight per day, such as near a large tree or in the shade of a building.
The great thing about this plant is that it has very few pests or diseases. This trouble-free veggie grows vigorously and performs well even for the most novice gardener. But there are still a few common issues to look out for:
Chard does not like competition. It is best to keep beds well-weeded. When weeding newly germinated plants, be sure not to confuse baby chard seedlings with lambsquarter and pigweed. These cousins of B. vulgaris resemble the plant closely in the early stages, however, they are easy to tell apart once they are larger. Chard will have brighter colored stems and more tender rounded leaves.
Deer, rabbits, and wildlife tend to love Swiss chard as much as we do. Be sure to keep your garden fenced or protect your plants with a floating row cover. If you struggle with local wildlife, look to plant other types of plants that may keep pests out of your yard near the outskirts of your gardening area.
Damping off is the most challenging issue when growing this plant. Fortunately, it only affects young seedlings. So, once you get your plants past the seedling stage, you don’t have to worry much longer.
Damping off is a fungal disease that creates fuzzy whitish mold on the soil surface and girdles young plants at the base. These pathogens thrive in damp, humid, stagnant air conditions. The easiest way to prevent damping off in seedlings is to avoid overwatering and utilize plenty of fans in your nursery. When direct seeding chard, these conditions are harder to control, so it is best to transplant or buy high quality plant starts from an organic nursery.
Excess moisture or extra humid conditions can result in downy mildew. This fungal pathogen is not deadly to the plant, but it is unsightly and not exactly appetizing. Downy mildew looks like white or grey powdery spores on the leaf surface.
The best prevention is proper spacing and air circulation between plants. Avoid overhead irrigation so that the chard is watered only from the base and leaves remain dry most of the time. You can also use a diluted neem spray to help treat downy mildew infections.
One of chard’s only major pests, leafminers create long tunnels through the leaves and lay tiny white carrot-shaped maggots. The best prevention is simply using row cover, insect netting, or insecticidal soap.
How to Harvest
The average maturity for a fully grown plant is 50-65 days. You will know it is ready to harvest when leaves are approximately 6” to 1’ long from the base. Simply cut or snap mature stems from the base of the plant, leaving smaller leaves in the center to promote regrowth.
During the peak spring season, chard can be harvested multiple times per week. For best results, remove older browning leaves and keep plants clean to help support new growth and prevent disease.
Frequently Asked Questions
Why is my chard dying?
Overwatering may lead to brown and wilting leaves. Young seedlings are especially susceptible to damping off from excessively moist conditions. This may result in a whitish powdery mold on the soil surface that girdles seedlings at the base, killing young plants.
Does Swiss chard come back every year?
Chard is an annual in growing zones 3 to 6 and an overwintering biennial in zones 6 to 10. It does not come back every year and needs to be replanted. However, in regions zone 7 and warmer, it can be grown as a short-lived perennial if it is continuously harvested and flower stalks are removed.
How long does chard take to grow?
The average days to maturity for full-size leaves is 50-60 days. Baby leaves can be harvested in just 28-30 days.
When can I plant chard outside?
Chard is cold-hardy and can be planted a few weeks before the last frost of the spring. It is best to start with robust plant starts and use row cover when planting them outside to help seedlings stay warm through mild night freezes.
Does rainbow chard need full sun?
Rainbow chard does best in full sunlight or light shade. Too much shade will result in poor yields and vigor.
How Cold Hardy is Chard?
When mature, chard is moderately cold-hardy to below freezing. Seedlings tolerate light frosts (30-32°F) and mature plants can withstand moderate frosts (20-25°F). As the weather cools, the sugars become more concentrated in the leaves, creating a sweeter flavor. Chard does well under row cover or low tunnels during the winter.
Swiss chard is an excellent leafy vegetable that’s easy to grow in any garden. It’s an excellent choice for organic gardeners, and easy for beginners to get the hang of. It’s extremely versatile and can be grown across a range of different growing zones, depending on your local soil conditions. Hopefully, after reading this guide, you have all the knowledge you need to start planting swiss chard in your garden before your next harvest!