Selecting an Indoor Site for Growing Spinach
Spinach likes cool temperatures in the range of 50º-80ºF (10º to 27ºC), and this is true even if you are growing it indoors in planting containers. Find an area in your house where the temperature stays within this range both day and night and where the plants will not be subjected to blasts of hot or cold air.
Spinach grows quickly in full-sun, but it also tolerates a fair amount of shade. Choose an indoor growing site for spinach with at least six hours of sun, or, put the plants under a grow lamp for six or more hours a day.
Selecting a Container for Growing Spinach Indoors
Full-grown spinach plants are not very large, and you can grow one or two plants successfully in a 1 gallon (3.8 liter) pot, or you can use a larger container and grow more plants together.
If you are growing your spinach to full-size, give each plant a minimum of 6 square inches (15 square cm) of space in the container. If you prefer baby spinach, you can plant the seeds or seedling at 2 to 3 inches (5 to 7.6cm) apart.
Fill the container with a good-quality potting mix or garden soil mixed with compost or decomposed manure, because spinach requires a nutrient rich soil. Be sure your container has drainage holes in the bottom, and place the container on a water-catchment tray.
Caring for Spinach Indoors
Growing spinach indoors requires much the same care as growing it outdoors, except indoors, spinach plants have more protection against pests like slugs and snails.
Care for your indoor spinach plants by:
- Making sure the plants have at least six hours of direct sun or light from a grow lamp each day.
- Water frequently and keep soil moist.
- Fertilize weekly with a dilute fish emulsion or other nitrogen-rich fertilizer.
- Keep temperatures in the recommended range of 50º-80ºF (10º to 27ºC).
- Harvest individual leaves or the entire plant before it begins to bolt, usually in 40 to 50 days after germination. Check the seed package for days to maturity.
You can also harvest outer leaves of the plant sooner, but do not pick more than 50 percent of the leaves, allowing the inner core of leaves to develop and continue growing.