Swiss chard 'Rainbow' (Swiss chard)

Plant your seeds just under a month before last expected frost. Sow seeds 1/2 to 1 inch (1 to 2 cm) deep, 2 to 6 inches (5 to15 cm) apart, in rows 18 to 24 inches (45 to 60 cm) apart. Chard seeds tend to produce more than one plant, like beets, and will require you to thin them to 6 to 12 inch (15 - 30 cm) spacings. Harvesting can begin with when leaves reach a decent size. Snip plants an inch or two above soil for cut-and-come-again harvest, or remove a leaf or two from each plant. Cut plants back down to 3-5 inches (6 - 12 cm) tall to encourage new growth, since older leaves get tough.
Whatever you do, be sure to avoid the growing point in the center of the plant.
Make succession plantings through late summer.