Growing spinach is an intense but deeply rewarding activity. A relative of Swiss chard and beets, spinach has a vigorous growth habit. A cool weather loving plant. Once you work out how to make the crop last as long as possible in the spring, when the lighter days can shorten the plants lifespan, it is a reliable addition to the vegetable garden.
Spinach (Spinacia oleracea) is also an ideal container plant.
As well as being easy to grow, spinach is also good for you. It is rich in iron, potassium, folic acid, thiamin and Vitamins A and C.
You can grow spinach as either a main crop or harvest the leaves when they are young for use in a salad.
If you want to learn how to grow spinach, this is your complete guide.
Rich in nutrients, growing spinach is not only good for you it is also pleasingly straightforward.
Selecting the Right Variety
An annual plant, spinach is classified as hardy in USDA Zones 2 to 11, but in warmer climates bolt resistant varieties are the best choice. These plants do best in temperatures between 35 and 75 ℉.
Most varieties reach a mature size and spread of 6 to 12 inches. A fast growing crop, the leaves are usually ready for harvest within a month of sowing the seeds.
Spinach comes in a range of varieties, these can be divided into two general categories, savoy and smooth leaf. In recent years baby or small leafed spinach, has become increasingly popular. When selecting your seeds, try to choose ones that will thrive in your climate.
F1 Amazon Seed is a true variety that produces round, dark green foliage. This cultivar tastes great when picked young, as baby leaves. It is perfect for both spring and fall growing.
Tetona F1 Hybrid is a productive variety known for its smooth, bright green foliage. Heat tolerant it is slow to bolt meaning that it can be harvested over an extended period. It is also mildew resistant making it an ideal choice for growers in damp climates.
Both Nordic IV and F1 Mikado are reliable, disease resistant cultivars. F1 Mikado is also bolt resistant. This is an oriental variety that can be sown from spring until fall, throughout the summer. It produces attractive dark green pointed foliage with a pink tip.
Gardeners in milder climates may want to try sowing seeds in the fall and harvesting overwinter. Cold Resistant Savoy and Bloomsdale Long Standing are both ideal for this. Razzle Dazzle, Melody, Indian Summer and Avon are also suitable for sowing in the fall.
Both Baby’s Leaf Hybrid and Melody are ideal for containers and window planters. Melody is particularly popular because it is a reliable, disease resistant variety.
Take the time to find a variety that suits your growing conditions. This makes care and maintenance a lot easier.
While garden centers may sell young plants, spinach is easily grown from seed. Seeds rarely keep well, so you will need to buy new seeds every year.
Growing spinach is best done in the cooler days of spring and fall. For a fall harvest sow in late August. Keep the seedlings in the shade and well regularly for a healthy September harvest.
You can sow seeds in Plant Growing Trays undercover or directly into the garden as soon as the soil is workable.
Sowing undercover enables you to harvest earlier. It also makes protecting delicate seedlings against unpredicted frosts a little easier. Remember, this is a quick growing crop. Sow the seeds no more than 3 weeks before you intend to transplant them into the garden.
Because spinach is so quick growing, and quick to go to seed, it is better to reseed every few weeks for a continuous crop than sowing one main crop to harvest over an extended period.
How to Sow
Sow the seeds in trays filled with fresh potting soil. Space the seeds in rows 12 to 18 inches apart as thinly as possible. You can use a seed dispenser if you find the seeds difficult to handle.
Alternatively, scatter the seeds and thin them out following germination. Seeds can be thinned out once they have developed at least one set of true leaves. At this stage they can be thinned out so that each seedling is spaced 6 to 10 inches apart. The thinned out seedlings are edible. You can also thin out as you transplant into the garden.
Cover the seeds lightly and water well. Use a spray bottle, such as the Yebeauty Plant Mister to moisten the soil. This gently moistens the soil meaning that the seeds aren’t disturbed or drowned during watering.
Growing spinach is temperature dependent. You will need to stop sowing seeds as the weather warms up, in May or June depending on where you live. Up until this point, successive sowings can be done every 10 days.
Fast growing varieties can also be sown in late summer for a fall harvest. When sowing in the fall, sow seeds heavily. Germination rates can fall by half in warm weather.
How to Transplant
Once the last frost date has passed and the seedlings are large enough to handle, they can be transplanted into the ground.
Before transplanting, dig the soil well. Growing spinach plants set out a deep tap root, so you should dig the soil over to a depth of at least 1 ft.
These are full sun plants but also tolerate shady positions. Late spring seedlings appreciate a partial shade position because it helps to keep them cool as the summer warms up.
The soil should be pH neutral and nitrogen rich. These plants won’t tolerate pH levels significantly lower than 6.0. If you are unsure of your soil’s profile, a soil test kit is a quick and reliable way to find out. Unsuitable soil should be amended before planting.
Cultivating this quick growing plant is also possible in pots or window boxes. Just make sure that the soil is well draining and the plant is in a light position.
You can also grow in containers. This is a good solution if space is limited. It is also useful if rabbits are a problem.
Fill a pot with good quality potting soil and plant as you would in the ground. Spinach grows happily in even a small, 10 to 12 inch pot or window box. Just make sure that your chosen container has drainage holes in the bottom and is clean.
Caring for Spinach
Keep the soil around the plants weed free. Weeds can smother young plants and deprive them of nutrients, stunting growth.
When to Water
Use a watering can to regularly water your growing crops. Aim to keep the soil evenly moist. It is particularly important to water growing plants regularly during warm weather. This helps to keep them cool and prevents bolting.
You will need to apply roughly 1 to 1.5 inches of water every week. In warm or dry climates you may need to water at least once a day. Watering a little every day is better than watering heavily once a week.
How Often Should I Fertilize?
A quick growing crop, you will need to regularly fertilize your plants. Evenly balanced fertilizer or those rich in nitrogen are ideal for producing large crops of dark, healthy foliage. Suitable organic solutions include soy meal and fish emulsion.
Water soluble or liquid fertilizers are recommended. These crops have shallow root systems, meaning that they can easily harvest the necessary nutrients when watered onto the soil.
How often you fertilize depends on the type of fertilizer you are using. The information on the fertilizer packet will tell you exactly when to apply but in general you will need to fertilize once every two to three weeks.
Mulching the soil around the base of the plant helps to improve moisture retention. It also keeps the soil cool and prevents bolt. If you apply an organic mulch it slowly breaks down, returning nutrients to the soil and further benefiting your plants.
What to Do if my Plant Produces Flowers?
The emergence of flowers is a clear sign of bolt. Bolting is caused by warm weather.
Just before the plant bolts it goes through a period of intense, quick growth. Its leaves will also change shape, becoming more arrowhead in form. As the plants grow taller they produce new, bitter leaves. Small clusters of flower buds also emerge.
Mulching the soil so that it remains cool and moist can help to keep plants cool and prevent bolt.
Bolt can be caused by lack of water or an increase in temperatures. Planting in a shaded position, mulching the soil and watering regularly can all help to keep plants cool and delay bolting. Growing in packed flower beds helps to shade the plants and keep them cool. It also adds interest to a garden.
Once the flower stalk emerges, the foliage will become bitter or completely lacking in taste. Pull up and discard bolted plants and sow a new crop in late summer as the temperatures begin to cool. Some gardeners try pinching off the flower buds to slow bolt down, but this is not very effective.
Alternatively allow the plants to flower and go to seed. The seeds can be harvested and sown the following year or in the fall. However, these seeds may not be viable. To increase the chances of viability, allow the seed heads to completely dry and brown on the plant. Harvest on a sunny day where the seeds are as dry as possible. Shake the seed heads into an envelope and store in a dry location until you are ready to sow.
If the temperatures fall and the ground begins to freeze before your crop has matured, mulch them with hay. The plants can be left, mulched in the ground until the spring temperatures begin to warm the soil.
You can also cover the plants with a fleece, such as the Agribon Floating Row Crop Cover. This protects crops from frosts and pests whilst also allowing moisture and light to reach the plants.
Once it is warm remove the mulch. As the soil warms up the plants continue to grow.
How to Harvest
You can harvest growing leaves within 4 to 6 weeks of sowing seeds, as soon as the foliage is large enough to taste. Using the cut and come again method, similar to harvesting other leafy greens such as lettuce, enables you to prolong the harvest and gives the plants time to grow.
To harvest, cut individual leaves away from the plant. Begin by harvesting the older, outer leaves. Allow the younger inner leaves to remain on the plant for a later harvest.
Begin by harvesting the older, outer leaves. This gives the younger foliage time and space to mature.
If you want a larger harvest you can also cut the entire plant. Cutting about an inch above the base, or crown, can encourage a new set of leaves to emerge.
Storing your Leaves
Don’t store your leaves alongside fruits such as tomatoes, apples or melons. These emit ethylene gas which can cause spinach and other crops to quickly spoil.
For long term storage you can freeze spinach leaves. Wash and dry the leaves before placing them in a resealable freezer bag. Microwave for a minute on high. Allow the leaves to cool before placing in the freezer. Use frozen spinach within 6 months of storing.
Common Problems and how to Prevent Them
These plants love cool, damp conditions. This means that mildew and fungal diseases, such as fusarium wilt can be common problems. Spacing your plants correctly, to improve air circulation, and keeping the foliage as dry as possible when watering helps to prevent these problems. If the problem persists, try growing one of the many mildew resistant varieties that are now available.
Regularly check crops for signs of aphid infestation. An application of homemade insecticidal soap wiped onto the foliage is a reliable way to cure this problem.
You may also need to install a fence if rabbits or other critters are a problem. Rabbits in particular can target growing leaves.
Leafminers can also target crops. A floating row cover is an easy way to protect your plants. You will also need to protect them from slugs and snails. Beer traps, copper tape, sawdust and eggshells are all effective organic ways to keep your plants safe.
Growing spinach is an easy process, just make sure to avoid growing in the heat of summer.
Growing spinach may seem complicated but it is infact one of the easiest plants that you can ever add to the vegetable garden. Quick to grow from seed it is an affordable option that is also ideal for beginners, container gardeners or keen window box growers. Just remember to sow around the heat of summer and keep the plants as cool as possible. In return you will be rewarded with a regular supply of great tasting, nutritious leaves.