in , ,

How to Plant, Grow, and Harvest Spinach

Spinach in the garden1
Spinach in garden

Spinach is a great-tasting early-season green. Next to the dandelion is the first green that can be harvested in early spring. It is also one of the best fall and winter crops.

Spinach is a cool-season annual. Plant spinach before the weather warms in spring and again as the weather cools in early autumn. (When days lengthen in late spring and the weather becomes dry and hot, spinach bolts and stops making new leaves.)

Spinach can be grown under cover in cold weather. Plant spinach in early fall then cover plants with a plastic tunnel or set plants in a cold frame for a harvest of fresh spinach, both tender leaves cut and come again or the entire plant in winter. Where winters are mild, spinach can be harvested without cover from October to April–and that is the time of year when it is not bothered by insects and diseases.

Here is your complete guide to growing spinach!

Where to Grow Spinach

  • Grow spinach in full sun in spring and autumn in most regions. Grow spinach in partial shade in warm regions.
  • Plant spinach in loamy soil rich in organic matter. Adding aged compost to the soil should ensure good drainage. Add two inches of aged compost or a commercial organic planting mix to the planting beds before planting then turn the soil to 12 inches (30cm) deep.
  • Spinach prefers a soil pH of 6.0 to 6.8. Spinach does not grow well in alkaline soil.
  • Spinach is hardy and thrives in cool weather; ideal spinach growing weather is 50°F to 70°F (10-21°C).
  • Warm weather and long days will cause spinach to bolt—that is it will flower and go to seed.

More tips: Spinach Planting.

Spinach seedlings
Sow spinach indoors 6 to 8 weeks before the last average frost date in spring.

Spinach Growing Time

  • Spinach is a cool-season annual. It needs 6 weeks of cool weather from seed sowing to harvest.
  • Spinach grows best when planted outdoors in early spring and then again in autumn. In mild-winter regions grow spinach outdoors in winter.
  • Sow spinach seeds directly in the garden as soon as the soil temperature reaches 35°F and the ground is workable.
  • Direct sow spinach outdoors or set out transplants 4 weeks before the last average frost date.
  • Sow spinach indoors 6 to 8 weeks before the last average frost date in spring for transplanting out as early as 4 weeks before the last frost. However, seedlings may suffer transplant shock if the roots are disturbed at transplant time.
  • Plant succession crops of spinach in spring every 10 to 14 days until daytime temperatures are consistently greater than 75°F. Succession planting will ensure a continual harvest of fresh spinach leaves.
  • Long days and temperatures greater than 75°F encourage mature spinach plants to bolt.
  • Young plants may bolt if exposed to temperatures below 40°F for one or two weeks after they come up.
  • In mild-winter regions, plant spinach in late summer or early autumn for harvest in autumn or winter; sow spinach for autumn harvest 6 to 8 weeks before the first fall frost.
  • Spinach can be grown through the winter everywhere in a cold frame or plastic tunnel.
  • Spinach planted in autumn can survive the winter under thick mulch; plants will resume growing in the spring. The best alternative is to grow winter spinach in a cold frame or plastic tunnel.
  • Temperatures of 20°F or below can freeze leaves and kill plants.
  • Don’t grow spinach through the summer in hot summer regions. Instead, grow New Zealand spinach or Malabar spinach which are heat tolerant.
Space spinach plants for even growth
Thin spinach to 12 inches apart; s[ace rows 12 inches apart.

Planting Spinach

  • Plant spinach seed ½ inch (12mm)deep. Cover seed lightly with soil.
  • Refrigerate seeds 1 week before sowing to help germination.
  • Sow seed 2 to 4 inches (5-10cm) apart.
  • Space rows 12 to 14 inches (30-35cm) apart.
  • Spinach seed will germinate in 5 to 9 days at 70°F (21°C) Germination will take longer if the soil is cooler, about 21 days at 50°F (10°C).
  • Thin spinach to 12 inches (30cm) apart when seedlings are 3 inches (7cm). Thin to the strongest seedlings. Remove weak seedlings by cutting them off at the soil level with scissors.
  • Thin spinach so that there is good air circulation between mature plants.
  • Grow 15 plants per household member.

More tips: Spinach Seed Starting Tips.

Container Growing Spinach

  • Spinach will grow in a container. Allow one plant for each 8-inch (20cm)pot; in large containers plant spinach on 10-inch (25cm) centers.
  • If you plan to harvest young leaves or young plants, you can grow 4 plants in a 12-inch pot. To harvest mature leaves, grow fewer plants in a pot.
  • Spinach is heat-sensitive; move containers into the shade on warm and hot days.
  • Containers will warm more quickly than garden soil in spring.

Companion Plants for Spinach

  • Grow spinach with other greens.
  • Spinach is a good companion in the shadows of tall crops such as corn, pole beans, or other members of the amaranth family such as beets and Swiss chard.

Watering and Feeding Spinach

  • Keep the soil evenly moist throughout the growing season to grow spinach quickly.
  • Water spinach at the base of the plant. The base of plant watering will avoid splashing muddy water onto leaves.
  • Mulch around spinach plants with straw, chopped leaves, or garden compost to prevent soil moisture evaporation and to avoid splashing soil on leaves.
  • Side dress plants with compost tea or a dilute solution of fish emulsion every two weeks during the growing season.
  • Side dress spinach with aged compost at midseason.
Mature spinach plants
Mature spinach plants can tolerate temperatures as cold as 20°F.

Caring for Spinach

  • Keep planting beds free of weeds to avoid competition for light, water, and nutrients.
  • Cut weeds at soil level rather than digging them out; spinach has a deep taproot but shallow feeder roots that can be injured easily.
  • Mature spinach plants can tolerate temperatures as cold as 20°F (-6.7°C), but it is best to protect plants from freezing weather by covering the bed with a portable plastic tunnel or row cover.
  • Spinach will bolt in temperatures greater than 75°F (24°C). If the weather warms, try protecting spinach under a shade cloth set over a frame.

Spinach Season Extension

  • Plant spinach in a cold frame in late winter (February), and the crop will be ready in early spring.
  • Choose heat- and bolt-resistant cultivars.
  • Grow spinach in light shade when the weather warms; plants in containers can be easily moved from a sunny location into a cooler, shady location.
  • Plant hardy cultivars for fall and winter harvest (check seed packets for hardiness).
  • Overwinter spinach plants by covering them with 8 to 12 inches of straw; when daytime temperatures reach 50° to 60°F in spring, gradually remove a few inches of straw each week.
  • In warm winter regions, plant spinach in fall as a winter crop.

Spinach Pests

  • Spinach can be attacked by aphids, flea beetles, leaf miners, slugs, and spider mites.
  • Knock aphids off plants with a strong blast of water. Pinch out heavily-infested foliage.
  • Remove leaves in which leafminers are tunneling-. Look for the eggs on the underside of the leaves. Floating row covers can exclude leafminer flies from the planting bed.
  • Spray flea beetles and spider mites with spinosad.
  • Use row cover over young plants to exclude attacks by flea beetles and caterpillars. Row covers can remain in place as long as temperatures are moderate.
  • Leafminers can spread quickly; till the soil at the end of the growing season to expose leafminer eggs to winter cold.
  • Keep slugs and snails away from spinach by sprinkling a barrier of diatomaceous earth around plants.

More on pests and diseases: Spinach Growing Problems: Troubleshooting.

Spinach Diseases

  • Spinach is susceptible to mildew, rust, and mosaic virus.
  • Plant rust and disease-resistant varieties.
  • Mildew and rust are fungal diseases. Spray-mist leaves with compost tea to prevent fungal diseases.
  • Plants hit by mosaic virus should be removed from the garden. The mosaic virus will cause leaves to be mottled or streaked with white or yellow spots.
  • Keep the garden clean of debris. Remove and destroy diseased plants.
  • Good air movement discourages fungal diseases such as downy mildew, white rust, and anthracnose.
  • Hot temperatures encourage Fusarium wilt and other fungal diseases, as well as promote bolting.
  • ‘Melody’, ‘Indian Summer’, and other cultivars resist mosaic virus and downy mildew. ‘Fall Green’ is a white rust-tolerant cultivar.
Spinach harvest
Cut leaves 4 to 7 inches long from plants that have 6 to 8 leaves.

Harvesting Spinach

  • Spinach leaves can be harvested as soon as they are big enough to eat.
  • Cut leaves 4 to 7 inches (10-17cm) long from plants that have 6 to 8 leaves. Cut the older outer leaves first. Allow the remaining young leaves to grow on to maturity.
  • If you harvest all of the leaves from a plant, cut the leaves 3 inches (7cm) above the soil; new leaves will grow on for a second harvest.
  • Very large leaves and older leaves can be bitter; harvest leaves sooner rather than later.
  • Lengthening days (days longer than 14 hours) and warming weather (temperatures greater than 75°F/24°C) will cause spinach to bolt, flower, and set seed. Bolting will mark the end of the harvest.

Storing and Preserving Spinach

  • Wash spinach thoroughly to eliminate the grit that sometimes sticks to crinkled leaves.
  • Spinach can be refrigerated for up to one week.
  • Spinach can be frozen canned or dried.
  • Spinach seeds can be sprouted.

Spinach in the Kitchen

  • Spinach can be eaten raw or cooked.
  • The dark green leaves of fresh spinach will add color to a lettuce salad.
  • Spinach can be pan-steamed in the water it is rinsed with.
  • Stir-fry spinach with garlic or bacon grease.
  • Bake spinach with alternating layers of pasta and cheese.
  • Add spinach to mushroom soup or cream soup.
  • Add spinach to omelets and quiche.

More tips: How to Harvest and Store Spinach.

Crinkle leaf spinach
Bloomsdale Long Standing spinach has crinkled leaves.

Saving Spinach Seeds

  • Spinach is a wind-pollinated, self-fertile annual.
  • Spinach will not cross with New Zealand spinach, but other spinach varieties will cross when the fine pollen is carried by the wind.
  • Plant spinach varieties apart to avoid cross-pollination or do not allow plants to flower.
  • Save seeds from late-bolting plants that are good-sized and abundantly leafy.
  • When green leaves turn yellow, pull up the plant and hand-strip seed stalks.
  • Spinach seeds will remain viable for about 5 years.

Spinach Varieties to Grow

  • ‘America’ (52 days): crumpled, dark green glossy leaves; mostly heat and drought tolerant.
  • ‘Bloomsdale Long Standing’ (43 days): thick crinkled, dark green, glossy leaves; slow to bolt; mosaic virus tolerant.
  • ‘Giant Noble’ (45 days): smooth flat leaves; leaves are large, thick, and pointed; resistant to mosaic virus.
  • ‘King of Denmark’ (46 days): rounded, slightly crumpled, dark green leaves; hardy plant.
  • ‘Melody’ (42 days) large plant with semi-crinkled leaves; resistant to mosaic and powdery mildew.
  • ‘Tyee’ (37-53 days): resistant to downy mildew.

Hot Weather Spinach Alternatives

Spinach Frequently Asked Questions

Q: What causes small white cottony blotches on the upper surfaces of spinach leaves (there are usually yellow spots on the undersides)?

A: This is called white rust, a fungus disease that can be controlled with an organic fungicide. Also, avoid overhead watering which can spread disease.

Q; What causes spinach to become stunted with yellow leaves and twisted leaves and stems?

A: This is caused by a disease called spinach blight or spinach yellow, which is spread by aphids. Grow resistant varieties (check seed packets) and control aphids as soon as they appear.

Q: What causes spinach to flower before it is ready to harvest?

A: Long days and warm summer temperatures force spinach to flower prematurely. Plant earlier in the spring or in fall, when days are shorter and cooler.

About Spinach

  • Spinach is a cool-season annual grown for its leaves.
  • Spinach forms a rosette of dark green leaves that can be flat or crinkled (savoy leaf spinach).
  • Spinach is related to beets and Swiss chard of the amaranth family.
  • Botanical name: Spinacia oleracea
  • Family: Amaranthaceae
  • Origin: Asia

More tips:

Spinach Growing Tips

How to Grow New Zealand Spinach

How to Grow Malabar Spinach

Grow 80 vegetables: THE KITCHEN GARDEN GROWERS’ GUIDE

Written by Stephen Albert

Stephen Albert is a horticulturist, master gardener, and certified nurseryman who has taught at the University of California for more than 25 years. He holds graduate degrees from the University of California and the University of Iowa. His books include Vegetable Garden Grower’s Guide, Vegetable Garden Almanac & Planner, Tomato Grower’s Answer Book, and Kitchen Garden Grower’s Guide. His Vegetable Garden Grower’s Masterclass is available online. Harvesttotable.com has more than 10 million visitors each year.

Comments

Comments are closed.
    • When spraying leaves and stems with a foliar fertilizer or pesticide be sure to follow the fertilizer or pesticide directions–and as a good practice error on the side of spraying a dilluted amount, rather than more. Test your spray on one or two plants before spraying the entire crop. A foliar spray heavy in nitrogen can burn leaves; the same is true of many liquid pesticides.

  1. Can I get some more details regarding cultivation of spinach .. I mean like I need details for seed production..for eg. Seed replacement ratio ,test weight ,seed treatment ,male sterile sources if any

  2. My seeds are germinating into very thin and long saplings for all types of seeds (same issue with spinach, peppers, tomato, bottle gourd). These saplings are dying after few days. I am using pure coco-peat as growing media, in net pots. I am keeping these in my garage, with in-direct light coming through the window glass for 6-7 hrs/day. I have noticed the same issue while placed under an open portico. I water them once in 1 or 2 days during day time, based on how dry the surface looks.
    Any idea on what is causing the saplings to die.

    • Place the flat or pots with seeds under a fluorescent light about 6 inches from the soil mix. When seedlings emerge, keep the light 3 to 4 inches above the growing seedlings for 12 to 14 hours each day. You will need to raise the light as the seedlings grow. You can purchase a grow light system with pulleys to raise the light. Place a fan near the seedlings turned to gentle breeze for 1 or 2 hours each day.

  3. The older leaves of my spinach are falling horizontally close to the the soil level when they’re supposed to be standing upright and vertical. What could be responsible for this?
    Plus which kind of fertilizer is best to use on my spinach, granular or liquid?
    Anticipating your reply. Many thanks!

    • Feed spinach with a dilute solution of fish emulsion or liquid seaweed. Older leaves can be harvested and eaten.

How To Grow Tips

How To Grow Tomatoes

How To Grow Peppers

How To Grow Broccoli

How To Grow Carrots

How To Grow Beans

How To Grow Corn

How To Grow Peas

How To Grow Lettuce

How To Grow Cucumbers

How To Grow Zucchini and Summer Squash

How To Grow Onions

How To Grow Potatoes

Cabbage in Raised Bed2

How to Plant, Grow, and Harvest Cabbage

How to Grow Broccoli

How to Plant, Grow, and Harvest Broccoli