Amaranthus spinosus Seeds | Spiny Amaranth
LATIN NAME: Amaranthus spinosus
COMMON NAME: Spiny Amaranth
Plant Profile
The paired axillary spines emerge directly from the stem node, not from the leaf itself, and they harden as the plant matures. The stem beneath is smooth, often tinged red, and branches freely from the base upward. A beginner who expects the soft, spineless leaf axils of a vegetable amaranth is usually surprised the first time a leaf rakes the knuckles.
Leaves are ovate to diamond shaped, alternate, and carried on long petioles, with a slightly mealy surface that rubs off on the fingers. The flowers are small, greenish, and packed into dense terminal and axillary spikes, and the plant is monoecious, bearing both kinds of florets on the same individual. The ripened seed is the part that matters to a seed buyer: a glossy, near-black, lens shaped grain barely a millimetre across, so small that a single spike can release hundreds.
Although its centre of diversity sits in the American tropics, the spiny amaranth now travels with people. It is established across the warm lowlands of Africa, South and Southeast Asia, and Australia, thriving on disturbed ground, riverbanks, and the edges of vegetable fields. Where it arrives it is as often welcomed as weeded, because the young shoots are a familiar cooked green.
A closer look at the plant shows why it travels so well: the tiny lens shaped seeds pass unharmed through the gut of birds and livestock, and the light chaff rides the wind on the smallest breeze, so a single season’s seed crop can colonise bare ground far from the parent plant.
The red and purple forms of the plant owe their colour to amaranthin, a betalain pigment that belongs to the same chemical family that colours beets and prickly pear. Unlike the anthocyanins found in most red flowers, betalains are stable across a wide pH range, which is why plant breeders and food scientists keep returning to amaranth as a natural colour source. The pigment concentrates in the leaf and stem rather than the flower.
Science & Biotechnology
Alongside the pigment, the leaves carry rutin and related flavonoids such as nicotiflorin, compounds studied for their effects on capillary strength. The same leaves are also high in soluble oxalates, which is the practical reason every traditional cuisine that eats this plant cooks it first and Discards the water. Eating the raw shoots in quantity is unwise for anyone prone to kidney stones, and the cooking step is not optional folklore.
In nutrition the young leaves are richer in iron and protein than many cultivated greens, which is one reason rural communities prize the plant where other vegetables are scarce. The seed is also edible once winnowed, though today it is mostly fed to poultry rather than to people.
Uses & Benefits
In West Africa the spiny amaranth is a staple potherb, gathered young and simmered with palm oil, onion, and ground pepper until tender. Across Southeast Asia and the Caribbean the same shoots are stir fried or added to soups, and the flavour is mild and spinach like once the oxalate rich water is poured off. Because the plant regrows quickly after cutting, a single patch can supply a kitchen for weeks.
Beyond the pot, the taproot has a long record in folk medicine as a diuretic and a wash for skin complaints, and the cooked leaf decoction is used in several regions as a tonic. These uses are local tradition rather than standardised therapy, and the plant should be treated as food first and medicine second.
Because the plant self sows freely, the simplest propagation is to let a few individuals stand and scatter, then thin the volunteers where wanted. For a tidy bed, start the seed in a warm frame and set out the sturdy seedlings once the risk of cold has passed and the soil has warmed.
Growing from Seed
Treat this as a warm season annual. Sow on the surface of a fine, well drained seedbed and press the dust fine seed in lightly, because it needs light to break dormancy and should never be buried deeply. A thin sift of sand or sieved compost is enough to hold it in place.
Seedlings appear rapidly once the soil is warm. Thin to the strongest plant every fifteen to twenty centimetres once they show their third true leaf, and do not crowd them, because air movement between stems keeps the otherwise healthy foliage from mildewing. Mature plants tolerate drought once established but crop better with steady moisture.
One caution for foragers: the spiny amaranth often grows beside stinging nettle and prickly bindweed, so gather with gloves and learn the leaf shape first. The smooth stem and paired thorns at every leaf base are the reliable marks that separate it from the edible leafy amaranths.
In the kitchen the young growing tips are best picked before the plant flowers, because once the seed spikes form the leaves turn coarse and the oxalate load climbs. A second cutting from the same plant keeps a steady supply through the warm months, and the flavour stays mild after the cooking water is discarded.
Among the amaranths this spiny form is the least likely to be confused with the grain types, because those lack the paired thorns entirely, yet all share the same basic leaf and seed chemistry, which is why the leafy and the grain forms are often discussed together in tropical agriculture and plant breeding alike.
Our Take
If you already grow leafy amaranths for the table, this prickly cousin is worth a row of its own, but keep leather gloves nearby for the harvest. For close botanical relatives and other amaranth choices, see the vegetable amaranth, the dramatic love lies bleeding, and the weedy Amaranthus palmeri. Wholesale seed for the amaranth group is available through specialist suppliers who list the category by the dozen.
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