Amaranth (Amaranthus cruentus) care guide

Amaranthus cruentus is commonly called amaranth in the United States. It may be grown for edible greens, grain, or colorful ornamental flower clusters, depending on the cultivar.

Amaranthus cruentus is a frost-tender annual. It completes its life cycle in one growing season and usually dies after exposure to freezing temperatures.

Amaranthus cruentus grows best in full sun, with at least 6 hours of direct light daily. It can tolerate some partial shade in hot climates, but reduced light may limit growth and color.

Water Amaranthus cruentus when the soil surface begins to dry, keeping moisture moderate and reasonably even. Established plants tolerate some drought, but severe dryness can cause early flowering and reduce leaf production.

Amaranthus cruentus commonly grows about 2 to 7 feet tall, depending on cultivar and growing conditions. Tall plants may need staking or a sheltered location to prevent lodging.

Amaranthus cruentus prefers warm conditions, generally around 70–85°F. Plant it outdoors only after the soil has warmed and the risk of frost has passed.

Amaranthus cruentus can be grown as a warm-season annual across much of the United States. In every zone, use local frost dates rather than the zone number alone to determine planting time.

Use fertile, well-drained loam for Amaranthus cruentus. It tolerates a broad soil-pH range, but growth is generally best in mildly acidic to neutral soil, roughly pH 5.5–7.0.

Amaranthus cruentus can grow in a large container with drainage holes, fertile potting mix, full sun, and consistent moisture. Choose a shorter cultivar when possible because mature plants can become top-heavy.

Amaranthus cruentus has moderate drought tolerance after establishment. Do not allow prolonged severe drought, especially while seedlings are developing or when growing the plant for tender greens.

Early flowering is often associated with drought, heat stress, crowding, cultivar response, or delayed transplanting. Keep plants evenly watered and harvest young shoots regularly if your goal is leafy greens.

Amaranthus cruentus may fall over because of its height, weak stems, wind, heavy flower heads, excessive nitrogen, or dense planting. Provide support early and avoid overly rich nitrogen fertilization.

Amaranthus cruentus may be attacked by flea beetles, leaf-feeding beetles, aphids, and other general garden pests. Inspect the undersides of leaves and use physical or locally approved controls when damage is significant.

Pale leaves may result from nutrient deficiency, water stress, root problems, or excessive fertilization. Check drainage and moisture first, then use a soil test before adding fertilizer.

Amaranthus cruentus usually performs well in fertile soil amended with compost or a balanced fertilizer used according to its label. Avoid excessive nitrogen because it can encourage weak growth and increase nitrate accumulation in edible foliage.

You can harvest Amaranthus cruentus repeatedly for greens by removing young leaves and tender shoot tips. Continued harvesting is most productive before heavy flowering, when foliage generally becomes less tender.

Sow Amaranthus cruentus outdoors after the last expected frost, when soil temperatures are at least about 60°F and preferably closer to 70°F. Cold, wet soil can delay or prevent germination.

Plant Amaranthus cruentus seeds very shallowly, about 1/8–1/4 inch deep, or barely cover them with fine soil. The seeds are tiny and may fail to emerge if planted too deeply.

Thin Amaranthus cruentus seedlings to about 6–12 inches apart for leafy production, or use wider spacing for large grain or ornamental plants. Rows are commonly spaced about 12–24 inches apart.

Amaranthus cruentus can be started indoors about 6–8 weeks before the local last frost date. Transplant carefully after hardening off, because mature roots and stems can be sensitive to disturbance.

Amaranthus cruentus commonly germinates in about 5–10 days under warm, moist conditions. Germination slows substantially in cool soil, particularly below approximately 50°F.

Young leaves may be harvested roughly 5–8 weeks after sowing, while seed maturity often takes about 90–100 days. Exact timing varies with cultivar, temperature, day length, and whether the plant is grown for greens or grain.

Amaranthus cruentus is normally propagated from seed. Sow fresh seed directly in the garden or start it indoors, then thin or transplant seedlings once conditions are warm.

Amaranthus cruentus can reseed itself if mature seed heads are left in place. Remove unwanted seed heads before seeds drop, because volunteer seedlings may appear throughout the garden.

Collect Amaranthus cruentus seeds when the flower heads are dry and the seeds release easily. Cut the heads into a bag, finish drying them in a protected place, then separate and store the clean seed in a cool, dry container.

Young Amaranthus cruentus leaves and tender stems are generally edible and can be eaten raw or cooked like spinach. Use plants grown from correctly identified, pesticide-free seed rather than unknown wild plants.

Amaranthus cruentus seeds are edible when properly cleaned and prepared, and some cultivars are grown specifically as grain amaranth. Do not assume every ornamental seed packet is suitable for food production.

Amaranthus cruentus leaves can contain oxalates and nitrates, with levels affected by cultivar, growing conditions, and plant age. People prone to kidney stones or advised to limit these compounds should ask a healthcare professional before eating large amounts.

Young Amaranthus cruentus leaves can be eaten raw, but cooking is commonly preferred. Cooking and discarding the cooking water may reduce some soluble antinutrients, although it does not eliminate every dietary concern.

Amaranthus cruentus usually flowers in summer to early fall, sometimes beginning about 4–8 weeks after sowing. Timing varies by cultivar, day length, temperature, and water availability.

Amaranthus cruentus produces dense, often upright or branching flower clusters that may be red, burgundy, green, gold, or purple depending on the cultivar. The small flowers are individually inconspicuous but form showy plume-like heads.

Remove flowers or developing seed heads if you want to prolong production of tender greens and limit reseeding. Leave them in place if you want ornamental display or mature seed.