About spinach and how to grow it
Spinach originally came from what is now Iran and nearby areas. It spread to China by A.D.647 and Spain by A.D. 1100, and came to North America with the first colonists.
Growing spinach is a problem for most home gardeners. The biggest obstacle is its tendency to bolt, which stops the production of usable foliage. Bolting in spinach is controlled by day length and is influenced by temperatures and variety grown. Long days hasten flowering, an effect increased by exposure to low temperatures during early growth and high temperatures in the later stage.
These circumstances make spring culture of a variety that is susceptible to bolting almost sure to fail; therefore, bolt-resistant (or long-standing) varieties must be used in spring. Some of the quick-bolting types that are otherwise good can be used in the fall, and in mild areas during the winter.
Make spring plantings in northern areas as early as possible, sowing seeds every 2 weeks until 6 weeks before daytime temperature reach 75 degrees. Make fall plantings about a month before the average date of the first frost. In mild winter areas plant anytime from October 1 to March 1.
Refrigerating seeds for 1 week before sowing will speed up germination if the soil is above 40 degrees. Sow seeds 1/2 inch deep and 2 inches apart in rows 15 to 18 inches apart; thin to 4 to 5 inches apart and use the thinnings in soups, salads and stews. Spinach likes fertile neutral moist soil. Harvest spinach when leaves are 6 to 8 inches long before the plants start to bolt. Cut off the outer leaves of the entire plant.
Besides the tendency to bolt, you may need to consider types that are resistant to three important diseases, downy mildew, or blue mold; mosaic virus, and spinach blight. Varieties differ by having either savoyed (heavily crinkled) or smooth leaves. Savoy types are harder to clean but are dark green, thick and usually preferred. Long-standing types are slower to bolt.
In the summer months when cool-season spinach fails the gardener, warm-season tropicals are available as another type to plant. They are as rich in vitamins as true spinach and comparable in flavor. (I know this as Malabar spinach, it is an attractive, glossy-leaved vine that grows rapidly to produce shoots in about 70 days. Start the seeds indoors and transplant seedlings in the garden in late spring. Train plants against a fence, wall, or trellis. Young leaves and growing tips can be cut throughout the summer).
Spinach may be served raw in salads or alone with dressing and a garnish of crumbled bacon and diced cooked eggs. For a traditional spinach salad, wilt the leaves with a hot dressing of bacon fat, then add vinegar, mustard, honey, chopped green onion and crumbled bacon.
A trick to preparing good cooked spinach is quick cooking in as little water as possible; what clings to the leaves after washing is enough. Cover the pot and cook until tender, 5 to 10 minutes. Drain and season with butter, salt and pepper and a touch of lemon juice.
Tip; spinach can be grown in containers or in window boxes.