How to Grow Amaranthus
Amaranthus
Amaranthus spp.
vegetableAmaranthus is a fast-growing annual plant prized for its nutritious leaves and grain-like seeds. It thrives in hot weather and produces vibrant foliage ranging from green to deep red and purple, along with striking seed heads. Both the tender greens and seeds are edible and packed with protein, minerals, and micronutrients.
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Example Amaranthus timeline · Pittsburgh, PA (Zone 6b)
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Plant Amaranthus
Around Apr 17Near Pittsburgh's average last spring frost.
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Tend & protect
Late spring–summerWatering, feeding, and pest-watch reminders.
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Harvest Amaranthus
Around Jun 6≈ 50 days after planting
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Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 3-11; best in warm season (spring through fall in cooler zones)
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Germination & Seedling
2-3 weeksSeeds sprout in 7-10 days in warm soil. Seedlings develop true leaves with characteristic oval shape.
Keep soil consistently moist but not waterlogged. Thin seedlings to proper spacing early to reduce competition. Provide bright light to prevent leggy growth.
Vegetative Growth
3-4 weeksPlant rapidly develops multiple leaves and stems, building a robust canopy. Foliage deepens in color if variety is colored amaranthus.
Water regularly during dry spells. Pinch off the top when plants are 8-12 inches tall to encourage bushier growth and delay flowering. Apply balanced fertilizer every 3-4 weeks.
Flowering & Seed Head Development
2-3 weeksTall flower spikes emerge (upright or drooping depending on variety). Flowers are tiny but densely packed on dramatic seed heads in red, green, gold, or purple.
Continue watering regularly. If growing primarily for greens, remove flower buds early to extend leaf production. For seed harvest, allow flowering to proceed.
Seed Maturation
3-4 weeksSeed heads become heavy and full. Seeds harden and develop a smooth, glossy coat. Foliage may begin to fade slightly.
Reduce watering frequency slightly once seeds are setting. Support tall varieties with stakes if needed. Begin harvesting leaves while seeds mature.
Harvest Ready
OngoingSeed heads are fully mature, seeds fall easily when rubbed. Leaves are tender and packed with nutrients throughout the season.
Cut seed heads and dry them indoors or allow to dry on the plant. Freeze or blanch and dry mature leaves. Store dried seeds in cool, dry conditions.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Use row covers on seedlings; spray with neem oil or insecticidal soap if infestation is severe
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Increase humidity; spray foliage with water; use miticide if severe
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Ensure good air circulation; avoid overhead watering; apply sulfur or fungicide if needed
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Spray with neem oil or insecticidal soap; encourage beneficial insects
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Handpick larvae; apply Bacillus thuringiensis (Bt) if population is high
Uses
Nutritious Leafy Green
CulinaryTender amaranthus greens can be eaten raw in salads or cooked like spinach. High in calcium, iron, magnesium, and vitamins A and C, making them a superfood vegetable. [source]
Grain Crop & Flour
CulinaryDried seeds are ground into nutritious flour or popped like popcorn for a crunchy snack. Amaranth grain is a complete protein containing all nine essential amino acids. [source]
Traditional Medicine
MedicinalAmaranthus has been used in traditional medicine systems to reduce inflammation, control bleeding, and support digestive health. Seeds and leaves contain compounds with potential anti-inflammatory properties. [source]
Natural Food Dye
HouseholdRed and purple amaranthus varieties produce vibrant natural dyes for fabrics and foods. The pigment, derived from betalains, is used as a natural food coloring. [source]
Pollinator & Bird Food
WildlifeAmaranthus flowers attract pollinators and hummingbirds, while mature seed heads feed goldfinches and other seed-eating birds during late summer and fall. [source]
This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.
Harvest Tips
For greens: Begin picking outer leaves when plants are 6-8 inches tall; continue harvesting throughout the season by cutting leaves just above leaf nodes. Leaves are most tender before flowering. For seeds: Allow plants to fully mature, then cut entire seed heads and dry indoors in a warm, airy location for 2-3 weeks. Rub dried heads gently to release seeds, winnow to remove chaff, and store in airtight containers.
Fun Facts
- 🌱 Amaranthus was a staple crop of the Aztecs and was called 'kiwicha' (meaning 'little seed'); it remains an important crop in Peru, Bolivia, Mexico, and parts of Africa today.
- 🌱 Some varieties can grow over 6 feet tall with seed heads the size of a human head, making them both a food crop and a dramatic ornamental accent in the garden.
- 🌱 Amaranthus is one of the few plant-based foods considered a 'complete protein' because it contains all nine essential amino acids in significant amounts, similar to quinoa.
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