Vegetable · Aizoaceae
New Zealand Spinach
Tetragonia tetragonioides
This heat-loving summer green carries thick, soft leaves you keep picking long after true spinach has bolted.
Full sun
Every 4–7 days
50–86°F · 10–30°C
50–70 days
Overview
As the summer heat drives true spinach to seed, New Zealand spinach is just filling out. It is no true spinach but a low, sprawling member of the fig-marigold family from coastal New Zealand and Australia, where it runs wild over dunes and shingle. Its leaves are thick and soft, and once cooked they carry much of the mild taste of true spinach.
The plant hugs the ground, its weak, trailing stems fanning out flat into a dense green mat a few feet across rather than rising into a bush. It holds up in hot, dry ground and keeps its hold even in the salty, alkaline soil that stops most greens. Each pinch of the tender growing tips draws out fresh, soft new shoots, so the plant keeps offering pickable leaves right up to the first fall frost.
The thick blades come with one detail to note: they hold oxalates and saponins in the raw leaf, so this is a green for the pot rather than the salad bowl in quantity. A short blanch in boiling water, with that water poured off, softens the leaves into good eating and yields a crop that keeps producing when other greens have quit.
Care
The short version: full sun and warm soil, with steady water through summer for the thickest, most tender leaves. Feed it monthly with a nitrogen-rich fertilizer, give the trailing stems plenty of room, and keep pinching the tips so soft new growth follows.
Light
Give it full sun for the thickest, most flavorful leaves, though it will take partial shade and keep pushing out foliage. More light draws out more of the tender tips worth picking.
Water
Once its roots are set it shrugs off heat and drought, but the blades stay plump and tender with steady, even moisture through summer. Water every 4 to 7 days, leaning to the shorter end in a heat wave or in loose, sandy ground.
Soil
Plant it in well-drained sandy loam worked full of organic matter. A pH of 6.5 to 7.5 suits it, and unlike most greens it holds on in alkaline and even salty coastal soil.
Temperature
This is a heat lover, at ease from about 50°F to 86°F (10°C to 30°C) and fullest in the warmth of high summer. Frost collapses the soft growth, so wait for warm soil before setting it out.
Humidity
Ordinary outdoor air suits it, somewhere around 40% to 70%, and it is not fussy either way. There is no number here to chase.
Feeding
Keep it fed for thick, leafy growth, since a hungry plant thins to a pale green and bolts early. A nitrogen-rich fertilizer monthly through the season, roughly 1/4 cup of N per 10 feet of row, holds the deep color and staves off premature flowering.
Pruning
Pruning and harvesting are one act here. Cut or pinch the top 4 inches of the growing tips often, and the plant pushes out soft new shoots and stays productive rather than running to seed.
Size & spacing
The plant stays low at 12 to 24 inches (30 to 60 cm) tall while its stems fan into a mat 3 to 4 feet (90 to 120 cm) across. Set plants about a foot apart within the row and leave roughly 3 feet between rows so the trailing stems have room to run.
When to plant
New Zealand spinach is a warm-season crop with no tolerance for frost, which collapses its soft stems. Start transplants indoors a few weeks ahead, set them out once the cold has passed and the soil has warmed, then pick young leaves and tips through the summer heat until the first fall frost.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Sow: Start transplants indoors 3-4 weeks before the last spring frost
- Plant: After the last frost when soil is warm; soak the hard seed in water ~24 hours before sowing and plant about 1 in deep
- Harvest: Harvest young leaves and growing tips continually through summer heat until the first fall frost
Hardiness
USDA hardiness zones: 9–11
Temperature: down to -7°C
Troubleshooting
This is a tough, easygoing plant, and most of what shows on the leaves and stems is either cosmetic or a sign of hunger. Reading the few signs below tells the real problems from the ones the plant will simply grow over.
Thick green leaves fading to a washed-out yellow with slow regrowth
When the deep green of the blades washes out toward a thin, pale yellow and regrowth after cutting drags, the plant is short on nitrogen, and a starved plant races to bolt and flower on top of it. A side-dressing of nitrogen fertilizer, about 1/4 cup of N per 10 feet of row each month, pulls the color back down into the leaves, with the soil kept evenly moist between feedings. That monthly feed holds the rich green tone and keeps tender leaves coming.
Fix:
- Side-dress with a nitrogen fertilizer
- Apply about 1/4 cup N per 10 ft of row monthly
- Keep soil evenly moist between feedings
Round holes punched through the fleshy leaf blades
Tiny round punctures scattered across the young leaf blades are the calling card of chewing beetles, usually flea beetles that land on the tender foliage. The pinprick holes look worse than they are, and a strong, well-fed plant fills back in and grows past them. A floating row cover laid over the seedlings keeps the beetles off the soft new leaves, and hand-picking or a treatment is worth it only once the holes start to riddle the fresh growth.
Fix:
- Tolerate minor cosmetic damage; vigorous plants outgrow it
- Use floating row cover over young plants
- Hand-pick or treat only if damage becomes heavy
Stems sprawl and flop across the ground
The stems lie down and wander because that is the shape this plant takes. It has a naturally trailing, weak-stemmed habit, so the soft stems fan out flat into a low carpet 2 to 3 feet wide instead of holding themselves upright, and crowding presses them into an even denser tangle. Set at 12 inches within the row and 3 feet between rows, the stems have room to snake across open ground, and pinching the tips draws out shorter, bushier side branches.
Fix:
- Allow 12 in within rows and 3 ft between rows
- Let stems trail into open ground or train through other vegetation
- Harvest tips to promote bushier branching
Toxicity
This is food, not poison, with one detail held in the leaf. The thick raw blades carry natural oxalates and saponins, which is why people cook them rather than eat them raw in quantity, and the same compounds make the raw greens a mild caution for pets and livestock. Cook the leaves for the table and keep large raw helpings away from animals, and everyone stays well.
Toxic to
Cats · Dogs · Horses · Rabbits · Livestock · Birds
Safe for
People
Cats Mild
A single nibble of a leaf rarely amounts to much. A cat that works through a mouthful after mouthful of the raw, oxalate-rich foliage may drool or turn queasy, and the plant is not a listed ASPCA toxin.
Dogs Mild
A dog that swallows a big wad of the raw, fleshy leaves can pick up a mild stomach upset from the oxalic acid and saponins packed in them. A small torn-off taste passes without trouble.
Horses Mild
The soluble oxalates held in the thick leaves make the raw greens a poor idea in quantity for horses, since a steady high-oxalate diet can throw off how they take up calcium. An occasional mouthful is unlikely to harm a healthy animal.
Rabbits Mild
Portions stay small. The oxalate load in the raw leaves keeps them off a rabbit's staple diet, though a little torn in among other greens is generally tolerated.
Livestock Mild
Grazing animals can crop some of the low, leafy mat, but the oxalic acid adds up when they feed on large amounts day after day. It belongs in a varied diet rather than as the main forage.
Birds Mild
Backyard hens and other birds tear at the soft foliage without much trouble, though the raw leaves are best offered sparingly because of the oxalates.
People Edible when cooked
For people the thick, soft leaves cook down into a safe, tasty green. A blanch of 1 to 3 minutes with the water poured off strips out much of the oxalate and saponin, and raw amounts stay modest for anyone prone to kidney stones.
Blanch leaves in boiling water about 1-3 minutes and discard that water before eating to reduce oxalate and saponin levels; avoid eating large amounts raw, particularly for people prone to kidney stones.
Helpline numbers
United States
ASPCA Animal Poison Control: (888) 426-4435 (fee applies)
Poison Control: (800) 222-1222
Canada
Poison Centres: 1-844-764-7669
Varieties
There is little to choose between here, since New Zealand spinach is nearly always grown as the plain species. A name or two still turns up in the seed catalogs.
Maori
This named selection shows up in extension references, though nearly all New Zealand spinach is grown as the plain, unimproved species.
Common (species type)
The wild-type species is the form most gardeners grow, since named cultivars of this plant are scarce.
How to propagate
Starting New Zealand spinach is simple, and it begins with the seed inside its hard, knobby fruit. The one point to know is how that tough fruit is coaxed into sprouting on time.
SeedEasy
After the last frost when soil is warm, or start indoors 3-4 weeks before the last frost · About 1-3 weeks to germinate (faster if seed is pre-soaked); roughly 50-70 days to first harvest
New Zealand spinach grows from seed carried in a hard, knobby fruit. Soaking that tough, corky fruit in water for about 24 hours before sowing softens it and speeds emergence. Sown roughly an inch deep and thinned to a foot apart, it germinates in 1 to 3 weeks, sooner from pre-soaked seed, and yields its first harvest of leaves and tips in about 50 to 70 days.
Myths
Its soft, fleshy leaves prove it is real spinach.
The name misleads the eye, because the plant belongs to the fig-marigold family (Aizoaceae) and shares no kinship with true spinach. It stands in as a heat-tolerant summer substitute, its thick leaves cropping on through the warmth that sends true spinach to bolt.
The thick raw leaves are as safe to graze on as lettuce.
The thick, soft blades carry oxalates and saponins, so they are not a raw salad green in quantity. Blanch them for 1 to 3 minutes and pour off the water before eating, and keep raw portions modest.
Its succulent leaves stand up to frost like true spinach.
This is a tender warm-season crop, and a frost will kill it outright, collapsing the soft stems and leaves. Sow or transplant only once the last frost has passed and the soil has warmed.