Horned Tetragon: planting, growing, caring for and harvesting

The Horned Tetragon (Tetragonia tetragonioides) belongs to the family of Aizoaceae. It owes its name to the small spikes or horns with which its fruits, capsules, are provided. This herbaceous plant is a forgotten vegetable many nutritional benefits since it is, among other things, well supplied with vitamins, minerals, fibers and is low in calories. It is eaten raw or cooked. In terms of taste, it is slightly iodized but its flavor is reminiscent of spinach, which is why it is also called New Zealand spinach or summer spinach. But these plants are botanically different. Be that as it may, the Horned Tetragon well deserves its place in the vegetable garden, especially as it is easy to cultivate. This is what we will see together.

Plant the Horned Tetragon

We can sow the Horned Tetragon from the month of may, even from April if you live in the south of France. The earth must be sufficiently warmed by the sun and it is essential that the risks of late frosts are completely eliminated. In a harsh climate, it is wiser to wait until June.

The germination temperature is between 20 and 30 ° C, it is necessary to soak the seeds in lukewarm water 24 hours before sowing. Then just:

  • To hoe the soil in the garden to loosen it up and take advantage of it to remove stones and weed roots,
  • To enrich the soil with organic material moderately acidic, of mature compost type, at the rate of two scoops per square meter,
  • To lighten the earth with a little sand,
  • To form furrows spaced more or less 1 meter from each other,
  • To sow in pockets of 4 seeds, these pockets must be at least 80 cm apart from each other,
  • Cover the seeds with 3 cm of soil,
  • To water in rain.

This plant is chilly. In areas where spring is slow to set in, it is therefore preferable to sow New Zealand Spinach under frame because to allow it to germinate, the ambient temperature must be at least 15 ° C. We can of course opt for sowing in pots. In this case, 3 seeds of the retorted Tetragon are placed per cup which are then placed well in the shade and in the light.

Ten to fifteen days after sowing, the cotyledons begin to emerge. As soon as they count four leaves, we proceed to thethinning in order to keep only one very vigorous plan per pocket or per bucket.

Cultivating the Horned Tetragon

The Tetragon needs a sunny exposure and sheltered from drafts. She likes them light, loose, humus-bearing, cool and well-drained soils. It is necessary to reserve a sufficient place for it and therefore to space the plants well. You might as well give it a very specific area of ​​the garden because it risks suffocating plantations that are too close.

Beware, the Horned Tetragon very difficult to tolerate transplanting. This is the reason why it is strongly recommended to use biodegradable cups that we place directly in the ground, in holes of the same size as the pots, respecting a spacing of at least 80 cm in all directions. If this type of container is not available, care must be taken to remove the whole root ball because the transplanting of a horned tetragon with bare roots is doomed to failure.

Maintaining a retort Tetragon

Undemanding, summer spinach can easily be grown by novice gardeners.


The Horned Tetragon needsmoderate watering but frequent. The soil should always be cool but not soggy. Even if it tolerates drought very well, it is tastier if it has benefited from regular watering. in dry weather. In any case, it must be watered sufficiently at the beginning to promote its rooting.


Once they are well rooted, we can lay a mulch at the foot of the tetragons to keep the soil cool. It’s a good solution to save water. It also saves time, especially since mulching also limits the development of unwanted weeds. The hoeing sessions are therefore less numerous.

Pinch and cut

It is during the summer that theend of rods New Zealand Spinach can be pinched to force branching. This simple little gesture is very useful in order to be able to benefit from an even more abundant harvest.

It is suitable in addition to remove its flower stalks as soon as they appear if one wishes to avoid the rise in seeds.

Parasites and diseases

At least the gardener can rest easy since the Horned Tetragon is not attacked by any parasite and is not susceptible to any disease. You just have to be wary of slugs and snails who appreciate its tender and fleshy young leaves.

Harvest the Horned Tetragon

New Zealand Spinach is very productive. Harvesting begins when the stems measure between 20 and 25 cm, that is to say a few weeks after germination, that is to say from summer and until the arrival of the first frosts.

We do not consume its stems. It is necessary pick only the leaves, one by one and not by handles. It is mainly the young leaves that are eaten raw. The oldest are preferably reserved for cooking. But young or not, the leaves of the Horned Tetragon must be harvested As things progress, depending on the needs, then consumed immediately after picking because they fade very quickly. It is undoubtedly because of conservation difficulties that we rarely find Tetragon leaves in the markets.

Once the seedlings of tetragon are successful, the harvests follow one another year after year without the need to intervene since this plant spontaneously reseeds. For this, we must not remove all its flower stems of course. In a small garden, it is essential to control it a little because it shows itself quickly intrusive. There is therefore no need to sow hundreds of seeds because the needs of a family of four are largely met with only three plants.

Photo credit: Forest & Kim Starr