Spinach for late fall plantings
UC Master Gardener
The weather of Fall 2012 is turning out to be very unusual. Warm temperatures continue to persist; days are still pleasant with sunshine and nights are barely chilly. The lack of rainfall is holding off the flush of winter weeds and keeping the fog away. All this makes for good spinach planting weather.
When early settlers came to America from Europe they brought spinach with them because it was green, tasty and nutritious. Although it has been around for a long time, it took Popeye, the cartoon character, to popularize its genuine healthful qualities as a cooked vegetable. Only in the 1980s when salad bars became so popular in the United States, and in particular in California, did spinach become recognized as a premier salad vegetable.
Spinach is a cool season vegetable crop that grows at temperatures of 40 to 85 degrees with 60-65 degrees being best. It can be grown in raised beds in a vegetable garden or planted alongside flowering annuals and perennials. Be sure to plant spinach where it will receive full sun in winter. Freezing weather harms young seedlings, but older plants can tolerate subfreezing temperatures for weeks.
Spinach seed is planted about one-half inch deep in the soil. The best soils are sandy loams, but a variety of soil types will grow good spinach. Sandy soils work well in winter months because they drain fast, but they need to be amended with compost so that fertility is sufficient for leaf growth. Heavier soils can be quite productive, if they are well drained and watered carefully. Amending clay soils with compost improves drainage. Spinach is particularly sensitive to saturated soil conditions, but it is only moderately salt sensitive.
Spinach is fast growing and short-lived and matures its leafy foliage in about seven weeks. It does not use much fertilizer, because it is a relatively small plant when full grown. When ready to harvest, you can either cut the entire plant or just remove the outer leaves. If you carefully cut the plant above the growing point, you can often obtain a second crop.
During periods of warm temperatures and long days (for example in the spring) or when plants don’t get enough water or nutrients, they are likely to produce seed stalks before making sufficient foliage growth. This is called bolting. Spinach then quickly goes to seed.
Spinach varieties are often classified by their heat resistance (less tendency to bolt) and by the curliness of their leaf. Savoy is a term used to describe varieties with crumpled, textured leaves and contrast with smooth or flat leaf spinach cultivars that predominate in commercial production in California.
Some typical home garden variety names are Avon, Catalina, Giant 157, Harmony, Melody, Oriental Giant, Palco, Renegade, and Teton. Seeds are available from common dealers such as Burpee, Ferry Morse, Park, and Renee’s Garden Seeds.
New Zealand spinach, which forms short runners and resembles regular spinach in leaf shape, is frost sensitive but tolerates warm weather much better than regular spinach. This is a better spinach to plant in the spring. It is productive all season and can be cooked or used raw in salads.
Growers near Porterville commonly plant spinach in October and November, and harvest huge spinach plants with big leaves in March and April, but their spinach is destined for freezing and not the fresh market. Consumers would find their spinach a little too tough for the salad bar, but just perfect for Popeye.
Michelle Le Strange is the Adviser for the UC Master Gardener Program of Tulare-Kings Counties. Ask the Master Gardeners your gardening questions, phone 684-3326, email firstname.lastname@example.org, or write to 4437B S. Laspina St, Tulare, CA 93274.