How to Grow Red Amaranth Molten Fire

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Red Amaranth Molten Fire

Amaranthus cruentus

vegetable

Red Amaranth 'Molten Fire' is a striking ornamental and edible grain amaranth with deep crimson-red foliage and dramatic drooping flower plumes. The entire plant—leaves, stems, and grain—exhibits intense burgundy-red coloring, making it as visually stunning as it is nutritious. Both leaves and seeds are edible, offering exceptional nutritional value with high protein and mineral content.

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Example Red Amaranth Molten Fire timeline · Pittsburgh, PA (Zone 6b)

  1. Plant Red Amaranth Molten Fire

    Around Apr 17

    Near Pittsburgh's average last spring frost.

  2. Tend & protect

    Late spring–summer

    Watering, feeding, and pest-watch reminders.

  3. Harvest Red Amaranth Molten Fire

    Around Jun 26

    ≈ 70 days after planting

Sample dates for Pittsburgh, PA. Sign up to get exact Red Amaranth Molten Fire dates for your own zip code.

Growing Conditions

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Sun: Full sun, 6-8 hours daily minimum; prefers intense heat
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Water: Moderate watering; keep soil consistently moist but not waterlogged. Drought-tolerant once established. Reduce watering frequency in cooler climates to prevent fungal issues.
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Spacing: 12-18 inches
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Days to maturity: 70-90 days for grain harvest; 40-50 days for leaf harvest
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Planting depth: 0.25 inches (direct sow); surface sow in warm soil

Soil

Type: Well-draining loamy soil
pH: 6.0-7.0
Amendments:
compost well-rotted manure perlite for drainage

Growing Zones

Find your zone →

Thrives in zones 4-11; treats as warm-season annual in cooler zones

3a 3b 4a 4b 5a 5b 6a 6b 7a 7b 8a 8b 9a 9b 10a 10b 11a

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Growth Stages

1

Germination & Seedling

7-14 days

Tiny seeds emerge with cotyledons (seed leaves) visible; seedlings develop first true leaves with emerging red pigmentation within 7-10 days.

Keep soil warm (70-85°F) and consistently moist. Thin seedlings to spacing distance once they have 2-3 true leaves. Minimize transplanting as roots are sensitive.

2

Vegetative Growth

3-4 weeks

Plant establishes strong root system and develops multiple stems with increasingly vibrant deep-red foliage. Height rapidly increases to 18-36 inches.

Water regularly and provide balanced fertilizer every 2-3 weeks. Ensure full sun exposure for best color development. Pinch growing tips if bushier plants are desired.

3

Flowering & Inflorescence Development

2-3 weeks

Dramatic drooping crimson-red flower plumes (panicles) emerge from top and axils of plant, creating striking visual display. Plumes elongate and deepen in color.

Reduce nitrogen fertilizer to encourage flowering over leaf growth. Maintain consistent water and heat. These plumes are edible and can be harvested at this stage for grain.

4

Seed Development & Maturation

2-3 weeks

Flower plumes fill with tiny nutritious seeds; entire plant deepens to almost black-burgundy color. Seeds mature and begin dropping naturally.

Reduce watering as plant matures to help harden seeds. Harvest plumes before seeds drop heavily; dry hanging or on screens. Allow some seed to drop for self-seeding if desired.

5

Harvest & Senescence

Ongoing until frost

Plant enters senescence with final color intensification; seeds ready for collection or grain threshing. Foliage begins to decline.

Cut plumes at base once fully dry and brittle for threshing. Continue harvesting leaves up until first frost. Pull remaining plant for compost.

Companion Planting

Plan your garden →

Plant with:

Avoid planting near:

spinach beet fennel black walnut

Common Pests

  • Use row covers on young plants; spray neem oil or spinosad; encourage beneficial insects

  • Increase humidity and air circulation; spray water forcefully to dislodge; use miticide if severe

  • Hand-pick; use Bacillus thuringiensis (Bt); remove weeds near planting

  • Ensure warm soil (70-85°F), avoid overwatering seedlings, use sterile seed-starting mix

Uses

🍳

Grain & Flour

Culinary

High-protein grain amaranth is gluten-free and traditionally ground into flour for porridge, bread, and baking. Seeds can also be popped like popcorn. Contains essential amino acids including lysine, rare in grains. [source]

🍳

Leafy Greens

Culinary

Young leaves are cooked like spinach or eaten raw in salads, offering a mild, slightly nutty flavor. Rich in iron, calcium, magnesium, and vitamins A and C. [source]

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Traditional Herbal Use

Medicinal

Amaranth has been used in traditional medicine for anti-inflammatory and blood-building properties. Rich in polyphenols and antioxidants with potential cardiovascular benefits. [source]

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Dramatic Garden Display

Ornamental

The vivid deep-red foliage and crimson drooping plumes make 'Molten Fire' a striking ornamental specimen, attractive to birds and pollinators. Ideal as a focal point in borders and containers. [source]

🦋

Pollinator & Bird Feed

Wildlife

Prolific flowering attracts beneficial insects; mature seeds provide food for birds and wildlife. Self-seeds readily, creating a natural food source. [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 grain: Wait until flower plumes are fully mature and dry (late summer/early fall); cut plumes and hang upside-down indoors to dry completely, then thresh by hand or rubbing over screens to separate seeds. For leaves: Harvest young tender leaves continuously from 4-6 weeks onward by pinching tops; this encourages branching. Plumes can also be harvested green for cooking. Seeds store for up to 2 years in cool, dry conditions.

Fun Facts

  • 🌱 Red Amaranth 'Molten Fire' was a sacred crop of the Aztecs and was associated with rituals and ceremonies; amaranth remains a staple grain in parts of Mexico, Peru, and India.
  • 🌱 Amaranth is a pseudocereal grain—not botanically a true grain like wheat or rice—but nutritionally superior in complete protein content and amino acid profile, including rare lysine.
  • 🌱 The dramatic red pigmentation comes from betalain and polyphenol compounds; these pigments are more concentrated and stable in 'Molten Fire' compared to other varieties, intensifying during heat and stress.

Gardening Terms

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