New Zealand Spinach

A sprawling, heat- and drought-proof summer green that never bolts - the plant Captain Cook's crew ate against scurvy. It is not spinach and not even a relative, and unlike spinach it should be blanched before you eat it.

Soak the hard seed capsule 24 hours, sow into warm soil, and expect slow, uneven germination and several seedlings per capsule. Then give each plant two feet of room and largely leave it alone.

The single most common failure with this plant is at sowing. What the packet calls a seed is really a hard, woody fruit capsule containing several seeds, and dry it can sit in the soil for weeks. Soak it for 24 hours in warm water before sowing (some growers nick it with a file as well), sow about half an inch deep into soil above 60°F, keep the bed evenly moist, and then wait — 10 to 28 days is normal. Two or three seedlings emerging together from one capsule is also normal; thin them to one with scissors.

In zone 6 and warmer, direct-sow after the last frost. Further north, soak and start in pots three to six weeks before the last frost and set the plants out once the soil has warmed — in a short summer, transplanting is what makes this crop worth the bed space.

After that it is undemanding to the point of being dull. Full sun, any reasonably drained soil including poor sandy and salty ground, no particular fertility, and 18 to 24 inches between plants, which looks ridiculous in June and is exactly right in August. Two or three plants supply a household all summer. It grows well in a large container or a hanging basket, where the sprawl becomes an advantage, and it is one of the few vegetables genuinely happy in a windy seaside garden.

Pinch once to make it branch, mulch under the sprawling stems, and pick regularly - picking is the care. The real job is deciding whether to let it set seed, because it will colonize the bed if you do.

Care is minimal. Pinch the growing tips once when the plant is about eight inches across to force it to branch low, mulch underneath so the sprawling stems keep their leaves off the dirt, and then harvest often — picking the tips is the pruning, and a plant cut back every few days stays tender and productive far longer than one left alone.

Water is optional in the sense that the plant will survive without it, but a deep soak every week or two in a long drought is the difference between tender leaves and small tough ones. Fertility is barely needed; rich ground gives lusher growth but this is not a hungry crop. Pests are close to nonexistent once the plant is established — slugs on seedlings and the occasional aphid colony on a shoot tip, and that is the list.

The one real decision is seed. Small greenish-yellow flowers appear in the leaf axils by midsummer and harden into woody knobbly capsules that fall and stay viable in the soil for years. If you want it back next year, do nothing. If you do not, run your fingers along the stems every couple of weeks in late summer, strip the capsules, and bin them rather than composting them. This matters most in mild coastal gardens, where it has naturalized on dunes and bluffs — do not plant it where it can walk out into open coastal ground, and pull volunteers beyond the bed.

Pick the top 3-4 inches of new growth every few days from midsummer until frost. Never strip the plant - each cut makes it branch, and it produces more the harder you pick it.

Harvest only the tender tips: the top three or four inches of new growth, with the soft stem attached. That is the whole technique. Older leaves further back are edible but tougher and stronger-tasting, and they are better left on the plant to keep it growing.

Pick every three or four days once the plant is established. Every cut makes it branch again, so a heavily-harvested plant is bushier and more productive than a neglected one — the opposite of true spinach, where a hot week ends the crop. Do not strip a plant bare; take a share from all over it and leave plenty of leaf behind.

The harvest runs from about 55-70 days after sowing until the first frost kills the plant outright, which usually means a solid three or four months of picking from one sowing. There is no bolting, no bitter phase, no succession sowing to plan. Give the tips a good rinse — the low sprawling habit means rain splashes soil onto them.

Use it fresh within a few days, or do the thing you have to do anyway - blanch it, squeeze it dry, and freeze it in portions. Blanching is the required preparation, so it is also the natural way to store a glut.

Fresh tips keep three to five days in a bag in the crisper. Store them unwashed and dry, and wash just before cooking; the thick leaves hold up better than spinach but surface water still turns them slimy.

Freezing is the obvious route for a surplus, and conveniently it uses the step you have to take anyway: blanch the tips for 1-3 minutes, drain and discard the water, cool, squeeze dry, and freeze in portions. That is exactly how you would prepare it for the pan, so frozen New Zealand spinach goes straight into soups, curries, pies and gratins later with no further work. It keeps about a year.

It does not dry into anything worth having, and it does not can well on its own. If you want it out of the garden and into the freezer in bulk, one heavy cut in late summer will fill several bags and the plant will have regrown within a fortnight.

Blanch first, always - one to three minutes, water discarded - then use it anywhere you would use cooked spinach. It is meatier than spinach and holds its texture instead of collapsing.

Blanch it first. Drop the tips into boiling water for one to three minutes, drain, and throw the water away; refresh in cold water if you want to keep the color. That single step removes much of the oxalate and all of the mild raw bitterness, and every cuisine that eats this plant — from New Zealand and Australian kitchens (where it is sold as warrigal greens) to Japanese cooking — does it. Skipping it gives you a slightly harsh, faintly metallic mouthful; doing it gives you a very good green.

After that, treat it as cooked spinach with more backbone. Squeeze it dry and sauté it with garlic and olive oil, fold it into eggs, frittata and quiche, stir it into curries, dals and soups, or layer it into spanakopita and gratins. It is meatier than spinach: it does not vanish to a spoonful in the pan, which makes it far better in pies, fillings and anything where you want the green to hold its own.

A note on raw: a leaf or two torn into a mixed salad is fine, and the flavor is pleasant and slightly succulent. A whole raw salad of it is not a good idea — the oxalate load is real and the raw bitterness is unappealing. Australian chefs who serve it raw treat it as a garnish, not a base.

Rich in vitamin A, vitamin C and iron and unusually high in protein for a leafy green - and high enough in oxalates that blanching is both the culinary and the nutritional recommendation.

New Zealand spinach is a nutrient-dense green: high in vitamin A (as beta-carotene), a good source of vitamin C, and useful for iron, calcium, magnesium and potassium, with a comparatively high protein content for a leaf. Its historical claim to fame is the vitamin C: it was eaten by ships' crews specifically as an anti-scorbutic, and it worked.

The counterweight is oxalate. Like true spinach and chard, this plant carries enough oxalic acid to bind a share of its own calcium and iron and to matter to anyone prone to calcium-oxalate kidney stones. Blanching in plenty of water and discarding that water removes a meaningful proportion of it, which is why the traditional preparation is also the sensible one. Vary your greens rather than eating any one high-oxalate leaf daily, and pair it with a little vitamin C and fat for better iron uptake.

Nothing came up because the seed was not soaked or the soil was cold. Bitter or harsh flavor means it was not blanched. Small tough leaves mean you are picking too far back or it is bone dry. Seedlings everywhere means the capsules dropped.

Nothing germinated: the classic failure. The woody capsule needs a 24-hour soak, warm soil (above 60°F), even moisture, and up to four weeks of patience. Cold soil and dry seed together mean a row that never comes up at all. Three seedlings in one spot: normal — several seeds per capsule; thin with scissors.

It sat there doing nothing until July: it grows slowly until real heat arrives, then takes off. Harsh, bitter or faintly metallic flavor: it was not blanched, or it was eaten raw. Boil one to three minutes and discard the water. Leaves small and tough: you are picking too far down the shoot — take only the top three or four inches — or the plant is severely drought-stressed; a deep soak fixes it.

It has smothered its neighbours: it sprawls two to four feet and will grow over anything low. Give it its own space, or the edge of a bed where it can spill out. Seedlings all over the garden next spring: the seed capsules dropped — strip them off in late summer next year, and hoe or pull the volunteers while small. Whole seedlings gone overnight: slugs, and only ever in the first few weeks. Plant collapsed after a cold night: frost; it is tender and dies at 32°F.

Built for hot, dry, salty, difficult sites: outstanding in zones 7-11 and in seaside gardens, workable everywhere with transplants, and perennial and self-perpetuating where there is no frost - which is where the caution applies.

This is a coastal plant from the southern hemisphere, and it is happiest in the conditions that defeat other greens. Zones 7-9: its best range — it takes Southern heat and humidity and mid-Atlantic July without flinching and produces from June to frost. Zones 10-11: frost-free, so it behaves as a perennial and one planting persists for years; this is also where it self-perpetuates most aggressively and where stripping the seed capsules matters. Zones 3-6: entirely growable, but soak the seed and start it indoors — direct-sown into a cool northern spring it wastes half the season getting going.

Two specialities are worth knowing. It is genuinely salt-tolerant, so it is one of the very few vegetables that will grow in a windy seaside garden with salt spray and sandy soil. And it is genuinely drought-tolerant, holding on and staying edible through dry spells that flatten lettuce and spinach.

Those same qualities are the reason for the caution on this entry. On the California, Gulf and Southeast coasts it has naturalized on dunes, bluffs and disturbed shoreline. In an inland vegetable bed it is simply a self-sower you manage with a hoe; in a coastal garden, treat the seed capsules as something to remove and dispose of rather than let fall.

It propagates itself, enthusiastically. Save the woody capsules as they dry, or simply let a few drop and transplant the volunteers - and cuttings root easily if you want a specific plant.

Seed saving could hardly be simpler. The woody capsules that form in the leaf axils dry and brown on the plant in late summer; strip them off, dry them thoroughly indoors, and store them cool and dry. They stay viable for three to five years, and because the plant is self-fertile and almost nothing else in a North American garden can cross with it, saved seed comes true. Remember the soak when you sow it again.

The lazier option is to let a dozen capsules fall in a corner of the bed and transplant the volunteers that appear the following spring, which is how most gardeners who grow this plant end up never buying seed again. That is the same behavior that makes it a nuisance when it happens where you did not intend it, so choose the corner deliberately.

Cuttings also work: a stem tip pushed into moist soil in warm weather roots readily, which is useful in frost-free zones for moving a plant you like or filling a gap without waiting on germination.

Collected in 1770 on Cook's first voyage and cooked for the crew as an anti-scurvy green - which is exactly how it got its name, and how it reached European and then American kitchen gardens.

The plant entered European horticulture through one of the most famous voyages in history. Joseph Banks and Daniel Solander, the naturalists aboard the Endeavour, collected it in New Zealand in 1770, and Cook's crew ate it cooked as a fresh green against scurvy — a serious matter on a long voyage and the reason it was worth carrying home. Seed reached Kew in the early 1770s, and by the nineteenth century it was a standard kitchen-garden vegetable across Europe and North America, valued for exactly the reason it is valued now: it gave you a spinach-like green through the summer months when spinach itself had bolted.

It was already food long before that. In Australia the same species is warrigal greens, eaten by Aboriginal peoples and now a fixture of modern Australian native-ingredient cooking, where chefs give precisely the same blanching instruction. The plant also grows wild on coasts in Japan, southern South America and around the Pacific.

Its American career has been quietly steady rather than fashionable — a reliable entry in seed catalogs for a century and a half, mostly grown by gardeners in the South and on the coasts who needed a green that did not quit in July. It deserves to be better known than it is.