Gardening for you: growing spring spinach
It’s time to plant spinach in the spring garden. Spinach is a cold hardy and super nutritious green crop. Spinach plants survive temperatures as low as 20°F. Seedlings started now will be at the ideal stage for transplanting into the garden. A good rule of thumb for spinach in the garden is to plant four to eight weeks before the last average frost. Lubbock’s average last frost is April 15-20.
Establishing a spinach crop is more successful when planted in the spring garden from transplants than from seed. If starting your own transplants is not practical, seeds can be sown directly in the garden now. Germination days vary with temperature – the cooler the temperatures, the longer the germination process and subsequent emergence. At soil temperatures of 70°F, spinach takes about six days to sprout. As of this writing, the ground temperature is 48°F; seeds planted now will take about two weeks for germination and emergence.
The first “leaves” to emerge from the seed are not true leaves, rather they are cotyledons (caw-tih-LEE-dons). Cotyledons are seed leaves, tender embryonic leaves that provide nutrients to the germinating embryo. The true leaves of seedlings most often have a different shape from that of their cotyledons. Spinach cotyledons are straight, long and thin. Nestled between the cotyledons are the true leaves which appear within days. The first true spinach leaves are usually round and flat. Successive leaves emerge from the rosette in the center of the plant and may be flat or tufted (wrinkled), with pointed leaf tips that are arrow-shaped or rounded in shape.
Grow spinach in full sun and soil amended with organic matter. Sow seeds ½ inch deep at 2 inch spacing with rows 12 to 18 inches apart; cover with soil, tamp lightly; keep soil moist until seedlings emerge. Spinach is a shallow-rooted crop requiring constant moisture.
Allow the seedlings to grow to several inches tall, then thin out each other plant to a final spacing of about 6 inches. Use thinnings as baby or gourmet greens.
Depending on the fertility of the garden soil, plants may benefit from light nitrogen applications. Indicators of low fertility are pale green leaves and slow or stunted growth. Liquid applications are more effective than granular nitrogen.
There are two main types of spinach: savoy leaf and flat leaf. Savoy types of spinach have thick, curly leaves that are ruffled. Savoy types are perfect in the vegetable garden. The other main type is flat hardwood, also called plain or smooth hardwood. These are the types most commonly available in grocery stores because sand and dirt tend to be trapped during growth and the flat leaves are easier to clean than Savoyard types.
Harvesting your own fresh spinach is a treat. Spinach grows well in containers too.
Ellen Peffley taught horticulture at the college level for 28 years, 25 of them at Texas Tech, during which time she developed two varieties of onions. She is now the sole owner of From the Garden, a vegetable farm. You can email him at [email protected]