With good varieties, adequate soil fertility, and regular watering, you can harvest from late spring well into fall. During more than 10 years of commercial growing experience, I've learned by trial and error the best ways to grow Swiss chard. Following are my tips for successful growing. It seems that many gardeners, including veterans, don't pay much attention to which variety they grow. That's a mistake.
Some varieties perform much better than others.
Most Swiss chard varieties are categorized as white or red, but you will also find a range of colors, including yellow, magenta, and striped. This refers to the stem or leaf stalk color, not the leaves. Large White Ribbed' is more productive but not quite as tender. Their weak spot is pests. White-stemmed 'Fordhook Giant' is the standard in our market garden.