Swiss Chard Seeds,
Japanese Mountain Spinach

This chard can be sown in early spring, 2-3 weeks before the last expected frost, and right on through summer. It germinates best when soil temperatures are between 50 F and 85 F, and unlike true spinach this selection from the mountains of Japan keeps producing in real heat, even at 104 F, so there is no need to stop sowing at midsummer. In milder winter climates, Japanese Mountain Spinach chard can be grown year-round, as it is frost-tolerant and will continue to produce in cooler weather. If you're not sure how to find your area's first and last frost dates, consult our blog post 'Our Experts Answer Questions, Share Resources.'

Sow Japanese Mountain Spinach chard seeds directly into the garden soil at a depth of about 1/2 inch, spacing them approximately 2 inches apart in rows that are 12 to 18 inches apart. After the seeds have sprouted, thin the seedlings to 8 inches apart to allow adequate space for the plants to mature. This variety can also be successfully grown in containers, which is convenient for gardeners with limited space.

Choose well-drained, moist soil and water regularly, especially during dry periods, to keep the leaves tender and flavorful. While Swiss chard is relatively drought-tolerant, consistent moisture will prevent bolting (premature flowering), which can affect the taste of the leaves. This plant is adaptable to various soil types, including those with higher alkalinity or salinity, and can grow well even without additional fertilization. However, incorporating organic matter into the soil can boost growth and improve leaf quality.

• Like other biennial plants, chard produces flowers and seeds in the spring of its second year, after it has been through winter.
• Chard is only winter hardy to about 15 degrees F, so in most areas, you must dig the plants in fall and replant them in spring if you want to save seed.
• Through winter, keep the trimmed plants packed in damp sand in the basement or another cool place.
• Set them out four to six weeks before your last frost date.
• Chard is wind-pollinated, so at least six closely spaced plants are needed for a good seed set.
• Look for greenish flowers followed by seed capsules clustered close to the stem. When the stems dry to brown, crush them inside a paper bag, and gather the largest seeds that fall to the bottom.
• Store them in a cool, dry place. Chard seeds will keep for at least three years, and often longer.