In this article: Learn all about growing spinach in your backyard garden- including how to start from seed and when to harvest!
Spinach probably doesn’t get as much notice as other cool weather crops like lettuce or cabbage, but it is actually one of the more hardy vegetables that is perfectly suited for year round gardening.
Spinach is a rewarding, easy to grow, vegetable that is great for gardeners of all levels.
Everything You Need to Know About Growing Spinach at Home
Spinach is in the Amaranthaceae family along with swiss chard, beets, and amaranth. It is a cool weather crop that can be planted 4-6 weeks before your last frost in the spring, or earlier under certain conditions. You can also plant it again in the fall and with protection, it can last through winter!
Spinach can withstand light and hard frost, making it perfect for you winter, early spring, or fall gardens.
Choosing Which Spinach Varieties to Grow
There are 3 basic types of spinach:
Flat-Leafed Spinach: Also called smooth leaf spinach, this is the most common type of spinach and is what you will find in most commercial frozen, canned spinach or on the shelves in the produce section of the grocery store.
The leaves are flat, smooth, and spade shaped. ‘Baby’ spinach is a flat leafed spinach that has been harvested early.
Savoy Spinach: Savory spinach has curly, crinkled leaves that are very dark green in color. It is crisp and somewhat bitter. Savoy spinach is best used in cooking.
Semi-Savoy Spinach: This spinach is very similar to savoy though with a less crinkled leaf. It is easier to clean. It is typically used for cooking.
Below are some of my favorite spinach varieties:
Amsterdam Prickly Seeded Spinach: This variety is more pointed and arrow shaped than most. Very hardy and is much slower to bolt in hot weather.
Giant Nobel: Large leaves make it easy to pick and clean. Holds up great to freezing or canning. Slow to bolt.
Winter Bloomsdale: One of the most popular varieties available. Good germination and quick harvest. Dark green savoyed leaves are sweet, tender, and have good flavor. Is slow to bolt.
Tyee: Dark green, semi-savoyed variety. Has resistance to bolt and downy mildew
Space: Smooth leaved variety with smooth round leaves. Slow to bolt and has downy mildew resistance. Freezes well.
Growing Spinach from Seed
Spinach is easily grown from seed, and can be started early indoors and planted out in early spring 4-6 weeks before last frost. Transplanting can be tough on spinach seedling so direct sowing is recommended.
Spinach seeds should be directly sown into the garden 4-6 weeks before your last frost date.
Sow your spinach seeds ½ to 1 inch deep, about 2 inches apart in rows.
Keep your garden beds evenly moist to encourage good germination rates.
Seeds should sprout within 7-10 days.
Using a cold frame can help you extend your spinach growing season, by allowing you to plant much sooner in the early spring or late winter.
Tips to Growing the Best Spinach
Spinach can grow in full sun or part shade. It grows well alongside larger plants such as peppers or eggplant, which will provide needed shade in the afternoon and extend your spinach season a bit. Simply plant the spinach at the base of the plant and it will help control weeds around the larger plant and the larger plant will provide shade for the spinach.
Keep your young seedlings and spinach plants well watered. Water will help them grow better and also keep the soil cooler. Do not over water and be sure that you have provided well drained soil. No plant roots like to stay wet!
Even though it is small, spinach is a heavy feeder. Spinach grows best in well-drained soil that is rich in organic matter and nutrients. The pH of your soil should be around 6.5-7.
For the best results, dig aged compost into the top 6 inches of your garden soil before planting your spinach seeds or spinach seedlings. Sometimes it is beneficial to prepare you spinach beds in the fall so that you can plant the seeds as soon as the ground thaws in the spring.
Regular applications of fertilizer can help your spinach grow faster. Fish emulsion or blood meal are great choices for fertilizers for spinach.
Proper spacing is important for good growth. If you spinach plants are too close together this can cause stunted growth or early bolting. Thin your plants to about 4 inches as they grow. These early harvests are great to eat!
Want a longer spinach harvest? Try succession planting! To extend your season, make successive plantings of spinach every 1-2 weeks all spring long.
Spinach does not like hot weather, once the soil has warmed try planting related leafy greens, such as New Zealand Spinach, for a summer harvest.
Begin sowing spinach seeds again in the fall. Direct sow the seeds beginning in Mid-August- or 6 to 8 weeks before the first frost in the fall. Watering the soil can help keep the soil temperatures down to allow better germination in warm weather.
Spinach is hardy down to about 15 degrees. Spinach can be grown in cold frames or under floating row covers to protect them from frost and cold temperatures. Depending on your climate you may be able to grow spinach all year long this way.
In the spring, spinach plants will begin to bold when the days get longer- or when the days are about 14 hours long. High temperatures can also speed up bolting. This means they stop putting out leaves and instead begin to grow tall and begin to form seed pods.
Growing Spinach in Pots
Since spinach doesn’t take up a lot of room it grows great in containers. Try using a long window box type planter since spinach has shallow roots and doesn’t need a really deep planter.
Remember that spinach is a heavy feeder, so choose a good organic potting soil and fertilize as needed if your plants appear stunted.
Make sure your chosen container has good drainage holes and watch for draining water and unblock the holes as needed.
Container-grown plants dry out more quickly than those in the ground. Check your pots daily and water as needed to keep the soil evenly moist.
Spinach is perfectly suited for growing aeroponically in a container like a Tower Garden. These amazing towers are perfect for crops like spinach and greens that don’t require pollination and can even be grown year round inside with grow lights.
Related Reading: 21 Crops You Can Grow in Containers
Spinach Pests and Diseases
Spinach doesn’t have too many pests and for the most part you should have no trouble with pests or disease in your spinach bed. That said, here are some of the problems you may run into:
Downy Mildew can occur in cool, humid conditions. The spinach leaves may have yellow spots and grayish mold on the underside. Good air circulation and planting resistant varieties can help prevent downy mildew.
Leaf Miners can burrow into your spinach leaves. Pick and discard any infected leaves. You can also companion plant with radishes to help deter this pest or use a floating row cover.
If you plants have yellowing leaves and are stunted you may be dealing with spinach blight. This virus can be spread by aphids so controlling them in your garden can help prevent blight. Wet conditions are prime for blight- so avoid overcrowding, water from below, and don’t work or harvest when the plants are wet.
Flea Beetles can be an issue in some gardens. I use diatomaceous earth for flea beetles and it’s very effective. Just be sure to reapply after rain or it won’t work as well.
Bolting is probably the biggest issue for spinach growers. Bolting is simply the plant flowering and going to seed. This happens when the temperatures are too high and the days are long. It can’t really be prevented, but try planting slow bolt or bolt-resistant varieties, keep the soil moist and mulched, and use companion plants to shade your spinach.
When to Harvest Spinach
Spinach can be harvested whenever it is the size you prefer- usually by 40-50 days.
Spinach leaves are more tender and flavorful when they are small and larger leaves tend to be tough and bitter.
To harvest you can dig up the entire plant (great if you are thinning the plants) or simply harvest the outer leaves of the plant and allow the inner leaves to grow longer.
Continue to harvest until your spinach bolts.
What Can You Do With Your Spinach Harvest?
Growing Spinach FAQ
How long does spinach take to grow?
On average it takes about 40-50 days to harvest spinach. This can change based on the variety you are growing. Generally, you can harvest spinach as soon as it has 5-6 true leaves. Just harvest a few leaves at a time- and this young, baby spinach is much more tender and has a sweeter flavor.
How deep are spinach roots?
For the most part spinach has a very shallow branching root system. This makes it perfect to grow close by other, larger crops. It does develop a deep taproot that helps anchor it and draw nutrients from deep in the soil.
Why aren’t spinach seeds aren’t germinating?
Most of the time germination problems are due to old seeds. Other problems could include:
- The temperature is too high- seeds can germinate in soil temperatures between 40-70F and daytime temperatures between 50-70F
- The soil is too dry (or too wet)
- You didn’t sow the seeds deep enough
How much room do you need to grow spinach?
Not much! You can plant seeds as close as 2-3 inches apart. This makes it perfect for small gardens, square foot gardens, and container gardens!
Can you grow spinach in full sun?
Yes, spinach can grow in full sun or partial shade. Just remember that it also prefers cooler temperatures, so once the weather warms in the late spring providing some afternoon shade can help you spinach grow better and prevent bolting.
Can you growing spinach in the winter?
Yes! Spinach can withstand temperatures down to 15-20F! This means it can handle light frost, snow, and even some hard frosts. Once it’s consistently cold with hard frosts, adding a cold frame can help you grow spinach even longer in the winter!
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