Spinach is an edible flowering plant from the goosefoot family and was native to Asia. Spinach is a popular vegetable loaded with nutritional value and considered by nutritional experts to be a “super food”. Superfoods are foods that are known to help reduce cholesterol, the risk of heart disease and cancer. Spinach is high in vitamin K, Folate, Vitamin A, C, and Beta Carotene. It also contains iron, calcium and is a great anti-oxidant.
Spinach can be prepared in a variety of ways including both cooked and raw. It is a very hardy cool-season vegetable that grows well in the home garden and can be planted at multiple times for successive harvests (both in spring and fall).
Conditions for Growing Spinach
Spinach is cool season vegetable that can tolerate colder weather and frosts. Spinach needs full to part-sun and moist, organically rich soil. Spinach does not grow well in highly acidic soils and performs best with a pH range of 6.3-6.8. Adding lime to your soil may be necessary. To determine your soil conditions prior to any amendments, have a soil test performed. Your local University Extension office can perform a soil test.
Spinach is a very cold-hardy plant and can be sown directly into the garden as soon as the soil can be worked in the spring. In southern states, spinach seedlings or seeds from the prior season may begin growing again in early spring, even with snow still on the ground! If you sow successively (every few weeks) you can enjoy your spinach over a longer period of time. Seeds should be planted about 1/2 an inch in the soil and spaced about 2-4 inches apart in rows 18-24 inches apart.
It is best to sow freshly purchased seeds, and not seeds saved from the last growing season. Sow about 15-20 seeds per each linear foot of soil. Water the seeds well after planting. If your soil has a high level of organic matter, fertilizer is not necessary; if not, a fertilizer high in nitrogen should be mixed into the soil during planting. Once the plants start to grow, you can thin them to about 4 inches apart. Placing top mulch down will help to conserve moisture.
Photo courtesy of Sbocaj at Flickr.com.
Care for Spinach Plants
Spinach should receive about an inch of water per week. If there has been little rainfall you can supplement by hand watering. As your spinach grows you will probably need to thin the seedlings, unless you are harvesting the plants at the same time (as well as the entire plant) Be careful not to disturb the other plants roots as you pull.
Weed as necessary but, again, be careful not to disrupt the fragile and shallow root system of the spinach. Adding a side dressing of nitrogen every 2-3 weeks will help ensure a healthy crop with deep green leaves.
Spinach takes about 40-50 days to mature. Your individual preference will also determine when you harvest the leaves. Some people prefer to eat smaller leaves, others larger. If you do not harvest the entire plant, pick the outer leaves first. The inner leaves will continue to grow and can be harvested later.
Spinach will not keep for long after harvesting. The best time to eat them, both for flavor and nutrient value, is right after picking. Be certain to wash the leaves well before eating. Spinach can be stored in the refrigerator for a few days (wash and dry them first) if you do not eat them right away.
Spinach Diseases and Pests
- Downy mildew and other fungal diseases
- Blight disease, also called cucumber mosaic disease. Planting disease resistant types will prevent this.
- Leafminers: Adult females will poke holes in the leaves to feed on sap. Their eggs are left on leaves. The larvae that hatches days later and feeds on the plant leaves, eventually making them inedible. There are both organic and chemical treatments for leafminer control.
- Caterpillars, including cabbage loopers, armyworms, and cornear worms. Caterpillars eat and destroy the spinach leaves. Inspect your plants closely for infestations. If the numbers are small, you can physically remove the worms and dispose of without further treatment. If the numbers become larger, there are both organic and chemical pesticides available to use.
Varieties of Spinach
The University of Illinois horticulture department’s website, Watch Your Garden Grow, recommends trying the following varieties:
Bloomsdale Long Standing (48 days to harvest; thick, very crinkly, glossy dark green leaves)
Winter Bloomsdale (45 days, tolerant to cucumber mosaic virus, slow to bolt, cold tolerant, good for over-wintering)
Indian Summer (39 days; semi-savoy; resistant to downy mildew races 1 and 2, tolerant to spinach blight)
Melody (42 days; lightly crinkled; resistant to downy mildew, mosaic; good spring or fall)
Tyee (39 days; dark green; heavily savoyed; tolerant to downy mildew; spring, fall or winter)
Vienna (40 days; very savoyed; medium to long-standing; tolerant to downy mildew races 1 and 2 as well as spinach blight)
Giant Nobel (43 days; large, smooth leaves; long-standing).
Olympia (46 days; slow to bolt; spring, summer harvest).