By Master Gardener Ellie Samuel
There are three main varieties of spinach: Savoy (Curly), Semi-Savoy and Flat Leaf. Baby spinach involves harvesting immature leaves. Most varieties mature in 40-50 days. Before planting, think about which kind of spinach you like to eat and how you will use it. Select disease-resistant varieties to avoid viruses and rust.
- Savoy has crisp, crinkly leaves and a firm texture that stands up to cooking or may be eaten fresh. Plant ‘America’ or ‘Winter Bloomsdale’
- Semi-savoy is less crinkly and is preferred by some because it’s easier to clean. Plant ‘Tyee,’ ‘Space’ or ‘Melody Hybrid.’
- Flat Leaf has large smooth leaves and is more tender than the curly variety, and, often, is eaten fresh. Plant ‘Olympia’ or ‘Grant Nobel.’
Also, when selecting varieties, consider whether you are growing spinach in the fall or in spring. Some varieties (such as ‘Winter Bloomsdale’) will tolerate light frost and will overwinter in milder microclimates or with winter protection. Other varieties (such as ‘Tyee’) are slower to bolt (i.e., go to seed) as spring warms up.
True spinach prefers well-drained, rich soil and a sunny location. Some light shade from taller plants in a succession garden is advisable if planted mid-spring or late-summer/early-fall which can be quite warm in Sonoma County. Amend your seed bed with compost or aged manure. Refrigerate seed one week before planting to encourage germination. Direct seeding is preferred; seed can be started indoors if soil temperature is not yet or is no longer at least 50 degrees. Sprinkle seed over a 2- to 4-inch wide band about 1/2-inch deep, and cover it lightly with soil. Thin to 3- to 4-inches apart when seedlings are 2-inches high. Use scissors at the soil line so as to not disturb the roots of plants chosen to remain. Because spinach is fast growing and short-lived, sow every two to three weeks for a continuous harvest. If container gardening, plant spinach in a pot at least 8-inches deep.
For a fall crop, sow seeds July through October (as late as four to six weeks before the first frost date—on average, about mid-November to early December in Sonoma County). Spinach at or near maturity can withstand moderate frost. If you live in an area with moderate winters, such as coastal Sonoma County, spinach may overwinter and grow again in late winter. In other areas, a row cover or cold frame may be required for winter protection. In the spring, sow the seeds as soon as the soil can be worked (February or March based the first frost date in your microclimate). Mid-April to early-May is the average last frost in Sonoma County for planning purposes. [Fun tip: Sow spinach seeds around emerging spring bulb foliage. You will have edible green leaves to cover bare spots left by deadheaded bulbs.]
Spinach requires even watering. Keep the soil moist, but not wet. Side dress spinach mid-season with compost, blood meal or kelp. The moist soil and nitrogen-rich amendments will encourage leaves to grow quickly so that they are tender.
Spinach can be harvested when leaves reach four to six inches on plants with at least eight leaves. Whole plants can be harvested at once; cut at the base. Or, outer leaves can be picked off which allows for a one or more additional harvests. Do not wait too long to harvest as larger leaves can taste bitter and the plant can bolt.
We don’t have to, like Popeye, eat spinach through a pipe. This highly nutritious and easy-to-grow vegetable can be eaten fresh, sautéed, blanched, boiled, creamed, pureed, steamed or fried. Add it to your salads, dips, sandwiches, sauces, wraps, casseroles, eggs, rice, pasta or smoothies.