Spinach should be cared for much like other leafy greens. Direct sunlight is best, but spinach can tolerate partial shade, especially during warmer seasons. Soil temperatures must be between 40 and 70 degrees for spinach to germinate and grow successfully; higher temperatures cause premature flowering. Use loose, slightly acidic soil and provide 1-2 inches of water per week. Add mulch around your spinach plants to manage moisture and weed growth.

Although spinach does best during cold, damp weather, this makes it more vulnerable to fungal diseases, including fusarium wilt, damping-off and downy mildew. To help combat these, ensure plenty of air circulation and water the plants first thing in the morning so the leaves can dry by evening. Also, watch for common pests such as aphids and flea beetles; use fencing to deter rabbits and other wild animals.

As a cool-season vegetable, starting spinach indoors may be necessary in warmer areas to maximize the growing season. Use seed-starting mix in a tray or other container with good drainage. Sow the seeds 2-3 inches apart and about half an inch deep. Keep the ambient temperature around 60 degrees and water them enough to keep the soil consistently moist. Use a windowsill or grow lights to provide sufficient UV light. When the seedlings develop two “true leaf” sets, thin or transplant the seedlings so they are about six inches apart. Transplant them when they are approximately one inch tall.

As soon as the outdoor soil is workable, it’s ready to plant or transplant spinach. Space the plants and rows by 12-18 inches. Succession plant every two weeks for a continuous harvest. In the spring, plant new seeds beneath taller plants to give them partial shade as temperatures warm. Container planting spinach is a great way to control temperatures and soil conditions. Use well-draining pots that are at least 14 inches wide and six inches deep.

Spinach goes from seed to harvest in about six weeks, and that requires a lot of nutrients. Add compost or balanced granular fertilizer to the soil when planting. When the plants have 4-5 true leaves, start applying a high-nitrogen fertilizer as a side dressing or liquid spray. Beware that too much fertilizer will create leaves that are big but less flavorful. Regular soil testing will determine what feeding is necessary.

Spinach can handle light frost, but more serious frost causes damage. In the coldest grow zones, add mulch and use row covers or low tunnels to continue growing outdoor spinach throughout late fall and early winter. Bring container plants indoors once air temperatures regularly fall below 40 degrees. In warmer growing zones (7-11), you can grow spinach throughout the winter with little or no care modifications.

You don’t need to do any specific pruning with spinach. Simply harvesting the leaves when they’re ready will spur new growth. We recommend removing any plants that show signs of damage or disease to prevent spreading.

There is no hard rule for when to harvest spinach. When the outer leaves are large enough to suit your fancy, trim them using garden scissors or shears. Leave the inner leaves so they can continue growing.