How to Grow SpinachDOWNLOAD FILE
May 25, 2016
Spinach (Spinacea oleracea)
- Family: Chenopodiaceae (Goosefoot)
- Season: Cool
- Ease of growing: Easy
- Nutrient needs: Medium
- Water needs: Medium
- Common propagation: Seed
- Germination temperatures: 35°F to 75°F
- Germination time: 5 to 22 days
- Viability: 2 to 4 years
- Direct sow: April to May (spring crop); July to early August (fall crop)
- Weeks to grow transplants: 3 to 4
- Start: March to April (spring); June to July (fall)
- Plant out: 4 weeks before last frost
- Typical Spacing: 3” x 12”; 6” x 18”
- Plants per square foot: 9 to 16
- Succession sow: every 2 to 3 weeks
- Days to harvest: 50 to 90 from seed; 30 to 70 from transplanting
Two basic types are available, smooth-leaf and savoy, which has crinkled leaves. Most gardeners prefer the smooth-leaf spinach because it is easier to clean.
Preparation and planting
Spinach is an early spring or late fall crop. The heat of summer will cause it to bolt and flower. Usually the crop is started from seed. Spinach is slow to establish. Begin transplants in spring for an early start, or sow spinach as early as you can work the soil. You can sow a second crop about two weeks later and third crop in late July for use in the fall. Spinach grows well in a neutral to slightly alkaline soil.
Keep the plants weed-free. The shallow, fibrous roots do not compete well with weeds. They will benefit from light-colored, soil-cooling mulch. Keep the soil moist for the fastest growth.
Insects: Flea beetles, leafhoppers, leafminers, aphids, certain loopers
Diseases: Damping-off, downy mildew, anthracnose, Cercospora leaf spot
Harvesting and storage
If you want to keep plants producing, harvest by pinching off the outer leaves when they’re large enough to use. Do not harvest more than 50 percent of the leaves from a plant. To harvest the entire plant, cut at the base and remove the older leaves. At close to freezing temperature and high humidity, spinach can be stored for one to two weeks.
Developed by James Manning, Undergraduate Research Assistant, and Daniel Brainard, Vegetable Extension Specialist; MSU Department of Horticulture; Gary Heilig, MSU Extension educator.