English Spinach
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What was it about ordinary canned spinach that made Popeye’s biceps bulge? Spinach is a nutritional powerhouse, and if you’re willing to indulge its finicky nature, the rewards are great.
Spinach and other dark leafy greens like kale and silverbeet are packed with calcium, folates, vitamin K and iron. Spinach is also rich in lutein, vitamins A and C, fibre and carotenoids. So, not only did spinach make him super-strong, Popeye may also have been protecting himself against osteoporosis, heart disease, colon cancer, arthritis, memory loss and cataracts. Imagine if he’d eaten fresh spinach!
English spinach (Spinacia oleracea) is not silverbeet, as many greengrocers claimed in my youth. Spinach has soft leaves on slender stems, while silverbeet has firm crinkly leaves with well-defined ribs and veins. Spinach is native to south-western Asia and is an annual.
Silverbeet is from the coast of Spain and Portugal and is biennial. It is also (somewhat strangely, given its heritage) known as Swiss chard.
Unfortunately, the other way to tell the two apart is that spinach is much harder to grow than silverbeet, but is well worth the effort.
Site and soil
Spinach likes good drainage, a rich soil with plenty of compost and will tolerate light shade. Try to remove stones and weeds and turn the soil well before planting.
Spinach is best suited to cool climates and (in the right spot) will be productive in Canberra throughout winter and spring. I use a cloche to protect young seedlings from frost in late autumn and to protect mature plants from the heat in late spring.
Planting
Spinach can be successfully grown from seeds or seedlings. Germination of seeds is possible in temperatures as low as 5 degrees C, although 10-16 degrees is preferable. Sow seeds 1cm deep either directly or in punnets. Each seed produces two or three seedlings and it is suggested that these clumps be planted together.
Seedlings should be planted or thinned to around 30cm apart. Spinach does not respond well to root disturbance, so plan your final position in advance.
Cultivating
Weeding and mulching are important to reduce competition and to create stable (cool and moist) growing conditions.
Spinach grown in poorer soils will benefit from application of organic liquid fertiliser or mulch enriched with nutrients, particularly nitrogen.
Harvesting
Pick individual leaves as you need them, from the outside of the plant, but make sure you leave enough for the plant to be able to photosynthesise. It is better to cut (rather than pull) the leaves to avoid damage to the root system.
Alternatively, cut the whole plant once it’s large enough to use. Harvest can usually start 4-6 weeks from planting.
Problems
The biggest problem with spinach is its tendency to bolt to seed as soon as conditions become even slightly unfavourable. This is particularly an issue in late spring when days become longer and temperatures increase.
Spinach also tends to bolt under water or nutrient stress. Mature spinach plants don’t suffer from too many pests, but can be occasionally attacked by slugs and snails.
Choosing and using
Although spinach is available to buy all year round, it is best (and cheapest) in winter and spring.
When buying spinach, choose bright green, fresh-looking leaves. Use them as soon as possible after purchase, or keep them for a few days only in a plastic bag in the crisper. Don’t wash them until you’re ready to use them.
The leaves need very little water to cook and if you want to retain all the good Popeye-sustaining nutrients, cook them only until they are wilted and bright green. Baby leaves are great for salads.
References and further reading
Organic Vegetable Gardening (Annette McFarlane)
BBC Gardening: www.bbc.co.uk/gardening
Botanica’s Organic Gardening (Judyth McLeod)
