Vegetable · Aizoaceae
New Zealand Spinach
Tetragonia tetragonioides
Plant this heat-loving summer green and pick tender leaves long after true spinach has bolted.
Full sun
Every 4–7 days
50–86°F · 10–30°C
50–70 days
Overview
When summer heat sends true spinach to seed, New Zealand spinach is just hitting its stride. It isn't a spinach at all, but a sprawling member of the fig-marigold family native to coastal New Zealand and Australia, where it grows wild on dunes and shingle. Cook the thick, soft leaves and they taste much like the spinach you know.
The plant spreads low and wide, trailing across the ground into a dense mat a few feet across rather than standing upright. It thrives where it's hot and dry, even tolerating salty and alkaline soil that would stop most greens. Pinch the tender growing tips through the season and the plant answers with fresh shoots, keeping the kitchen supplied right up to the first fall frost.
One thing to know going in: the raw leaves hold oxalates and saponins, so this is a green you cook rather than pile into a salad. A quick blanch in boiling water and a pour-off of that water makes it good eating, and you trade a little prep for a crop that keeps giving when nothing else will.
Care
The short version: full sun and warm soil, with consistent water through summer for the best leaves. Feed it monthly with a nitrogen-rich fertilizer, give it plenty of room to sprawl, and keep picking the tips to keep new growth coming.
Light
Give it full sun for the heaviest, most flavorful leaves, though it will take partial shade and keep producing. The more light it gets, the more tips you'll have to pick.
Water
It shrugs off heat and drought once it's settled in, but the leaves taste best and stay tender with steady, even moisture through summer. Water every 4 to 7 days, leaning toward the shorter end in a heat wave or in sandy ground.
Soil
Plant in well-drained sandy loam worked with plenty of organic matter. A pH of 6.5 to 7.5 suits it, and unlike most greens it shrugs off alkaline and even salty soil near the coast.
Temperature
This is a heat lover, comfortable from about 50°F to 86°F (10°C to 30°C) and happiest in the warmth of high summer. Frost ends it, so wait for warm soil before planting out.
Humidity
Ordinary outdoor air suits it fine, somewhere around 40% to 70%, and it isn't fussy either way. There's no number to chase here.
Feeding
Keep it fed for steady leafy growth, since a hungry plant pales and bolts early. Apply a nitrogen-rich fertilizer monthly through the season, roughly 1/4 cup of N per 10 feet of row, which also helps hold off premature flowering.
Pruning
Pruning and harvesting are the same job here. Cut or pinch the top 4 inches of the growing tips often, and the plant pushes out tender new shoots and stays productive instead of running to seed.
Size & spacing
Plants stand only 12 to 24 inches (30 to 60 cm) tall but sprawl into a mat 3 to 4 feet (90 to 120 cm) across. Set them about a foot apart within the row and leave roughly 3 feet between rows so the trailing stems have somewhere to run.
When to plant
New Zealand spinach is a warm-season crop with no tolerance for frost. Start transplants indoors a few weeks ahead, set them out once the cold has passed and the soil has warmed, then harvest young leaves and tips straight through the heat of summer 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 goes wrong is cosmetic or down to hunger. Learn the few signs below and you can sort out the real problems from the ones the plant will simply outgrow.
Pale, yellowing leaves with sluggish regrowth
Washed-out color and slow regrowth after cutting usually point to nitrogen deficiency, and a hungry plant also tends to bolt and flower early. Side-dress with a nitrogen fertilizer, about 1/4 cup of N per 10 feet of row each month, and keep the soil evenly moist between feedings. A monthly feed through the season keeps the leaves dark and the harvest 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
Small round shot holes chewed in the leaves
Those little punctures are the work of chewing beetles, usually flea beetles that hop onto the young foliage. The damage looks worse than it is, and a strong, well-fed plant simply grows past it. Cover seedlings with a floating row cover early on, and only hand-pick or treat if the holes start to overwhelm the new 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
This is just how the plant grows. New Zealand spinach has a naturally trailing, weak-stemmed habit and forms a low carpet 2 to 3 feet wide rather than standing tall, and crowding only makes the flopping worse. Give each plant 12 inches within the row and 3 feet between rows, let the stems trail into open ground, and pinch the tips to push bushier branching.
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, but it comes with a small catch. The leaves hold natural oxalates and saponins, so 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 nibble rarely causes much, but a cat that eats a lot of the raw, oxalate-rich leaves may drool or get an upset stomach. It isn't a listed ASPCA toxin.
Dogs Mild
Dogs that gulp down a big helping of raw leaves can end up with mild stomach upset from the oxalic acid and saponins. Small tastes tend to pass without trouble.
Horses Mild
The soluble oxalates make the raw greens a poor idea in quantity for horses, since regular high-oxalate forage can throw off how they take up calcium. An occasional mouthful is unlikely to harm a healthy animal.
Rabbits Mild
Keep portions small. The oxalate load means the raw leaves shouldn't be a staple in a rabbit's diet, though a little mixed with other greens is generally tolerated.
Livestock Mild
Grazing animals can handle some, but the oxalic acid adds up if they feed on large amounts day after day. Offer it as part of a varied diet rather than the main forage.
Birds Mild
Backyard hens and other birds pick at the foliage without much fuss, but the raw leaves are best given sparingly because of the oxalates.
People Edible when cooked
This is a kitchen green for people, safe and tasty once cooked. Blanch the leaves for 1 to 3 minutes and tip out the water to cut the oxalates and saponins, and go easy on raw quantities if you are 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 isn't much to choose from here, since New Zealand spinach is almost always grown as the plain species. Still, a name or two turns up in the seed catalogs.
Maori
A named selection cited in extension references, though almost all New Zealand spinach is grown simply as the unimproved species.
Common (species type)
The wild-type species is the form most gardeners grow, since few named cultivars of this plant exist.
How to propagate
Starting New Zealand spinach is straightforward, and seed is the way it's done. The one trick worth knowing is how to coax the hard seed 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
Grow it from seed, and give the hard, knobby fruit a head start by soaking it in water for about 24 hours before sowing. Sow roughly an inch deep and thin the seedlings to a foot apart. Expect germination in 1 to 3 weeks, quicker if you pre-soaked, and your first harvest of leaves and tips in about 50 to 70 days.
Myths
New Zealand spinach is a kind of true spinach.
Despite the name, it belongs to the fig-marigold family (Aizoaceae) and isn't related to true spinach at all. It just stands in as a heat-tolerant summer substitute that keeps producing when real spinach has long since bolted.
The leaves can be eaten raw and freely like lettuce.
The leaves carry oxalates and saponins, so they aren't meant for the salad bowl in big helpings. Blanch them for 1 to 3 minutes and pour off the water before eating, and keep raw portions modest.
It shrugs off frost like regular cool-season spinach.
This is a tender warm-season crop, and a frost will kill it outright. Sow or transplant only after the last frost has passed and the soil has warmed.