Spinach is a cool-season crop, more versatile than most because it can be served cooked or raw, and can be picked very young for gourmet greens or allowed to mature. Rich in vitamins and minerals, it’s an essential part of any vegetable garden. And your home-grown spinach will be a world apart in flavor from the stuff you see in supermarkets! So let’s get growing:
The best time to grow spinach depends upon where you live. For those in Northern climates, early spring is the best time to sow spinach, but folks in warmer areas can grow it in early spring or in fall for a winter harvest. Spinach is a cool-weather crop, but if your crop lingers on after the weather grows hot, you can try shading it with shade cloth to get just a little more out of the harvest before summer kicks in.
If you’re unsure of how to tell what time is best for your hardiness zone or climate, consult your local county extension agency for the best dates to sow crops according to where you live. Each state has a Land Grant Agricultural University that provides detailed information on plants, gardening, landscaping, insect control, etc. These universities also publish booklets and provide online information for all types of gardening and plants.
Spinach does best when grown in full sun, but will tolerate partial shade. Plant in well-drained, fertile soil with lots of organic matter mixed in, with as close to neutral pH as possible. If you’re starting in spring, prepare your soil this fall because late winter weather can make a mucky mess out of digging. Mix in a few inches of compost or well-aged manure to a depth of 8 to 10 inches and remove any rocks or large clumps in the process.
Sow seed ½ inch deep in rows 12 to 18 inches apart. Space seeds about 1 inch apart to begin with, but once seedlings reach an inch tall, thin them to 4 to 5 inches apart – remember, you can save the thinned seedlings for salads, too! Keep moist until germination occurs. Germination usually takes 8 to 10 days, but when sowing a late summer or fall crop, germination can be hastened by placing seeds in the refrigerator for 1 week prior to sowing.
In spring, sow successive plantings about a week apart until 6 weeks before daytime temperatures are above 75 degrees F to ensure a constant supply of spinach. Start sowing again in late summer for a fall and winter crop – spinach may stop growing once freezing weather arrives, but it will overwinter in warmer areas and start growing again in early spring.
Spinach has shallow roots and requires ample, consistent moisture to perform its best. If you’ve prepared your soil with good compost or aged manure, it shouldn’t require much fertilization throughout the season, but you can apply an all-purpose fertilizer (according to package directions) if the normally dark green leaves start to yellow. An inch-thick top-dressing of compost or mulch helps to keep roots cool and moist and discourages weeds.
Once the plant has at least four to six true leaves, you can start picking young outer leaves as needed for fresh use, but cut entire plant off at soil level when leaves are 6 to 8 inches long and before the flower stalk forms. Each variety has a different maturation rate, anywhere from 30 to 50 days.
Different spinach varieties can be more cold-tolerant, heat-tolerant, fast maturing, etc. Choose the right variety based upon where you live and the growing conditions of your garden.
Spinach leaves can either be smooth or crinkled (savoyed).
Pick young leaves for fresh salads and use older, larger leaves for cooking – stir-fries, sautéing, casseroles, soups, stews, etc.
For those in warmer climates who don’t ever really get a “cool” season – Hello South Florida! – or those that want to grow spinach throughout summer, try Space Hybrid. This variety stands up to high heat better than others we have seen. Or you can always grow spinach for baby greens in a pot on the windowsill indoors!
Give Easy Tunnels and Cold Frames a Try!
If you’d like to try growing spinach this fall and into the winter, chances are you will need frost protection. To extend your season by several weeks, a very effective tool is Easy Tunnel, a removable polypropylene row cover mounted on steel hoops. You just extend the tunnel over your plants, sink the ends of the hoops into the soil, and you’re good — the breathable fabric raises the temperature within the tunnel by several degrees, yet still lets in light and air!
For season-long protection, a cold frame will help keep temperatures above freezing, shelter tender plants from wind and rain, and extend the active growing period. Basically, cold frames are structures with four sides and a hinged, transparent top, usually made out of glass or plastic, that you can open and close depending upon the outside temperatures. They’re used during cold weather as mini-greenhouses, and also do a great job of starting seeds and overwintering tender ornamentals in pots. Cold frames are a great investment in the year-round garden!
Become a Multiseason Spinach Grower!
Spinach is too good (and good for us) to restrict its growth to spring and fall. Get creative with timing, succession planting, and frost protection, and you may find yourself harvesting those succulent greens almost year-round!