It’s not surprising that spinach plants are a staple of the kitchen garden, since they’re so delicious, nutritious, and easy to grow. They’re rich in vitamin A as well as many other nutrients, and this cool-weather vegetable is most productive when sown as a succession crop. Read on to learn more!
Spinach is a versatile addition to any garden, and in addition to traditional spinach plants, there are also crinkled leaf and savoy varieties available. If you want to learn more about this species, including how to grow it in your garden, then this is the guide for you.
Varieties of Spinach Plants
The variety that you choose to grow will in part be dictated by where you are growing. Gardeners in warmer climates should grow either bolt-resistant or quick-growing varieties. The good news is that even when your growing constraints are taken into account, there is still a wide range of spinach plants to choose from.
Here are some of the most common and interesting varieties to grow:
Atlanta AGM: A reliable hardy variety. It’s happiest in cold temperatures, making it ideal for a winter garden.
Palco AGM: This delicious variety is both slow to bolt, and mildew resistant.
Bloomsdale: A classic, thick-leaved savoy spinach that copes well in cold climates. It’s heavy yielding, but can be prone to bolting at the start of the summer.
Regiment: An F1 hybrid variety that is mildew resistant. This heavy-yielding spinach plant produces rich green leaves that stay tender even when they grow large.
Winter Bloomsdale: A crinkled leaf variety that grows best in autumnal temperatures. This reliable plant is tolerant to mosaic viruses.
Tyree: Resistant to downy mildew and will happily grow in both the fall and the spring.
How to Plant Spinach
You can begin to sow spinach seed six weeks before the last local frost date, or as soon as the soil is workable. Planting spinach as early in the spring as possible allows for an extended growing season. If your soil doesn’t freeze, you’ll be able to plant it in February for a March harvest.
Spinach likes loose, nitrogen-rich, well-draining soil. In terms of light requirements, this unfussy plant will grow in sun and partial shade. In warmer climates, planting in the shade of taller plants—such as beans—provides sun shelter and prevents bolting.
Fertilizing and improving the soil isn’t necessary. However, richer soil will intensify the plants’ sweet flavor. Work up to 2 buckets of well-rotted organic matter per square meter to sufficiently enrich the soil. You can further improve it by raking in 150g/5oz of general fertilizer.
Before sowing spinach plants, work the soil to a depth of at least 1 ft. This is because spinach forms a deep taproot. Working the soil loosens it, removing any rocks or pebbles that could impede your plants’ growth.
Sow seeds directly outdoors at a depth of about half an inch, and plant 12-15 seeds per foot. Spinach struggles to germinate in warmer weather, so heavy seed sowing increases the germination chances.
Following germination, once the seedlings are about an inch tall, thin them out to a spacing of 2-4 inches. If you’re growing more than one row of spinach plants, space the rows about 12 inches apart.
For an earlier harvest, try sowing spinach seeds under covers in late winter or early spring. Transplant outside when the soil has warmed and the seedlings are a healthy size. Be warned, however, that this isn’t always a successful method. Spinach seedlings are difficult to successfully transplant.
Sowing seeds every couple of weeks—known as succession planting—will provides you with a steady supply of spinach throughout the season. In cooler climates, sow seeds until mid May. After this date the weather becomes too warm to successfully grow spinach plants.
Start sowing winter crops in August. You can carry on sowing until late September, when the temperature becomes too cold. Gardeners in all but the coldest USDA zones can try growing spinach in cold frames, or under heavyweight row covers.
Caring for Spinach Plants
Spinach is similar to lettuce in growth habits and care needs.
Watering and Feeding
Over-watering or water stress can cause plants to bolt. Try to keep the soil moist but not soggy. If in doubt don’t water. You’ll need to water more often during warmer weather.
Spinach doesn’t require feeding, but applying compost tea or fish emulsion solution when the plants have produced four true leaves encourages healthy growth.
Thin out seedlings once they’ve reached about an inch in height. The required space depends on the variety you are growing so check the seed packet.
Keep the area around your spinach plants weed-free. Not only can weeds sap nutrients and moisture from your plants, but overcrowding can stunt growth and encourage plants to bolt. Pulling up weeds can harm spinach roots. Instead, spread a light mulch of straw, hay, or grass clippings around your plants, since mulch suppresses weeds.
Warm Weather Care
If the temperature reaches over 80F, cover the crop with a shade cloth. This helps to keep plants cool and deter bolt.
Spinach tolerates cold temperatures as low as 15 °F. It will also survive a frost. Unless you live in a mild area you’ll need to protect plants from the fall onwards. Cover plants with cloches or a cold frame. You can also mulch the crown and cover with a horticultural fleece.
Common Spinach Plant Problems
Since spinach is a cool weather crop, it may bolt in warmer climates. You can get around this problem by either growing bolt-resistant varieties, or sowing quick-growing varieties in the spring and fall. Keeping the soil moist also helps to slow or prevent bolt.
One of the benefits of growing cool-weather crops like these is that pests aren’t a major issue. The most common problem is leaf miner larvae. Their burrowing habit will turn cause tan patches to appear on leaves. To prevent attacks, cover crops with floating row covers. If a spinach plant does fall victim to leaf miners remove and destroy the affected leaves. Prompt action prevents the pest from spreading to other crops.
Another potential problem is spinach blight. This is spread by aphids and causes leaves to turn yellow. It also stunts plant growth. Making sure that there is room between the spinach plants for air to circulate will prevent this disease.
The easiest way to avoid leafminer and aphid attacks is to grow disease-resistant cultivars.
Birds and slugs can also attack young plants. Slugs can be controlled by chemical and natural methods. Birds, especially pigeons, can quickly destroy rows of young seedlings. To discourage bird attacks, cover the plants with a mesh or horticultural fleece.
Spinach plants grow well alongside other leafy greens, as well as garden peas, leeks, strawberries, eggplants, and radish. Swiss chard and spinach is a particularly happy combination that also works well with cauliflowers, brassicas and passion fruit. As mentioned earlier, growing spinach plants in the shade of taller crops such as beans, corn, and peas will reduce bolting.
Plants to avoid
Although spinach plants will happily grow alongside most other plants, never grow them alongside potatoes. This will harm the growth of both plants.
Harvesting Spinach Plants
You can begin to harvest as soon as the plants have at least 6 leaves that are about 3 or 4 inches long. Carefully cut away the outside leaves. This extends the plant’s productivity, especially if you’re growing in the fall.
Harvest the entire plant at the first sign of bolt, as mature or bolting plants taste bitter and unpleasant. Use a sharp knife to cut the main stem as close to the surface of the soil as possible.
Once harvested, wash the leaves and use them fresh for the best flavor. Young spinach leaves are best used fresh and raw in salads. Older, thicker leaves should be cooked before eating.
Storing Spinach Plants
Like all other vegetables, spinach starts to lose its nutrients almost as soon as it is harvested. To store in a refrigerator, wrap the spinach in a paper towel and place in a clean container. This will keep it fresh for up to 10 days.
If you want to freeze your spinach plants, you’ll first need to blanch the leaves in boiling water for no more than 2 minutes. Then cool the leaves in an ice water bath for 2 minutes.
Drain the cold water and squeeze excess moisture from the spinach by carefully twisting it with your hands.
Handfuls of wet spinach can then be formed into balls and wrapped tightly in a plastic wrap. These can then be placed in large freezer bags and stored for up to 14 months in the freezer. Defrost before using.
As we have seen, spinach plants are easy to grow and care for. With successional planting you will be able to harvest the crop all summer long, if not all year long. It’s little wonder why this great-tasting, nutrient-dense, low-maintenance plant is such a vegetable garden staple worldwide.