How to Grow Swiss Chard in North Carolina

Check the soil pH in a well-draining area that gets at least six hours of sun each day in fall the year before planting. Amend acidic soil with 1-3/4 to 2 pounds of elemental sulfur per 25 square feet to raise the pH by one point, until it reaches Swiss chard’s ideal range of 6.0 to 6.8.

Distribute 1/4 pound of granular 8-8-8 NPK or 10-10-10 NPK fertilizer over the soil between March 15 and May 1, using a drop spreader, if planting a spring crop. Fertilize between Aug. 1 and Sept. 15 if planting a fall crop in eastern North Carolina, and between Aug. 1 and Oct. 15 if planting a fall crop in western North Carolina.

Spread 2 inches of compost over sandy or loamy soil, and 4 inches of compost over clay soil, using a shovel. Work the fertilizer and compost into the soil 6 to 8 inches deep, using a spade fork or shovel.

Plant the Swiss chard seeds 1/2 inch deep and spaced 6 inches apart in rows spaced 18 to 24 inches apart right after fertilizing and composting. Scrape soil over the seeds until covered.

Dig a 1-inch-deep furrow 3 to 4 inches to the side of each row of planted seeds, using a trowel. If you planted two rows, evenly spread 2 ounces of granular, 8-8-8 NPK or 10-10-10 NPK fertilizer in each furrow. If you sowed four rows of seed, evenly spread 1 ounce of granular 8-8-8 NPK or 10-10-10 NPK fertilizer in each row. Backfill the furrows with excavated soil.

Water the soil with 1 to 2 inches of water after planting. Water the soil once a week after planting, on the same day each week, with 1 to 2 inches of water. Use 1 inch of water during weeks with moderate rainfall, and 2 inches during dry spells.

Mulch the soil with 1 to 2 inches of shredded bark, shredded leaves or straw. Scrape the mulch 1 to 2 inches away from where you planted the seeds, and 1 to 2 inches away from the stems when they emerge.

Sprinkle 1 cup of granular, 8-8-8 NPK or 10-10-10 NPK fertilizer over every 25 square feet of soil, when the chard reaches 8 inches tall. Distribute it evenly among the rows of plants and keeping a distance of about 4 to 6 inches away from the stems. Water the fertilizer in with about 1/2 inch of water if you don’t expect rain for a couple days.

Snip Swiss chard leaves from the plants as needed during the growing season, using garden shears for the task. Thin out the Swiss chard to 12 inches apart, leaving only the healthiest plants, when the plants grow to between 2 and 2 1/2 feet tall, using garden pruners for the job. Harvest the leaves starting 60 to 70 days after planting if you don’t take them earlier.

Check the leaves regularly for leaf miners. Although Swiss chard is relatively disease and pest free, they sometimes attract leaf miners, especially if planted near beets or spinach. Leaf miners dig, or “mine,” their way through the center of chard leaves, leaving darkened, raised, serpentine-like trails behind on the leaf bottoms. Cut away any damaged leaves if you find leaf miners in them.

Mix together 1 ounce of 1.2 percent azadirachtin -- an organic insecticide that targets leaf miners -- with 1 gallon of water in a pesticide sprayer if several leaves are affected by leaf miners. Spray the leaves until covered on both sides every seven to 10 days until the problem clears up.