How to Grow Tricolor Amaranthus Illumina

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Tricolor Amaranthus Illumina

Amaranthus tricolor 'Illumina'

vegetable

Amaranthus tricolor 'Illumina' is a striking ornamental and edible amaranth cultivar prized for its vibrant foliage featuring bright red, golden yellow, and green variegated leaves. The plant produces both ornamental foliage and edible leaves and grains, making it valuable for both decorative and nutritional purposes. It combines stunning visual appeal with practical culinary and nutritional benefits.

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Example Tricolor Amaranthus Illumina timeline · Pittsburgh, PA (Zone 6b)

Plant Tricolor Amaranthus Illumina
Around Apr 17

Near Pittsburgh's average last spring frost.
Tend & protect
Late spring–summer

Watering, feeding, and pest-watch reminders.
Harvest Tricolor Amaranthus Illumina
Around Jun 6

≈ 50 days after planting

Sample dates for Pittsburgh, PA. Sign up to get exact Tricolor Amaranthus Illumina dates for your own zip code.

Growing Conditions

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Sun: Full sun, 6-8 hours minimum daily; more sun intensifies leaf coloration

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Water: Moderate watering; keep soil consistently moist but not waterlogged. Water deeply at the base to avoid fungal issues. Amaranthus is somewhat drought-tolerant once established but performs better with regular moisture during the growing season.

📏

Spacing: 12-18 inches

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Days to maturity: 50-70 days for full foliage color and harvestable leaves

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Planting depth: 1/4 inch; press seeds lightly into soil

Soil

Type: Well-draining, fertile loamy soil

pH: 6.0-7.5

Amendments:

compost aged manure balanced fertilizer (10-10-10) perlite or sand for drainage

Growing Zones

Find your zone →

Thrives in zones 2b-11b; grows best as a warm-season annual in zones 2-8, and as a perennial in warmer zones

2b 3a 3b 4a 4b 5a 5b 6a 6b 7a 7b 8a 8b 9a 9b 10a 10b 11a 11b

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Growth Stages

Seedling

7-14 days

Tiny seedlings emerge with cotyledons and develop their first true leaves. Foliage begins showing hints of color variation.

Keep soil warm (70-80°F) and consistently moist. Thin seedlings to proper spacing once 2-3 true leaves appear. Provide bright light to prevent leggy growth.

Vegetative

3-4 weeks

Rapid leaf growth begins; plants develop multiple stems and the characteristic tricolor variegation becomes more pronounced with reds, yellows, and greens appearing distinctly.

Water regularly and fertilize every 2-3 weeks with balanced or slightly nitrogen-rich fertilizer to encourage leaf production. Pinch growing tips early to encourage bushier growth if desired. Ensure full sun exposure for best color intensity.

Peak Foliage

3-5 weeks

Plant reaches mature height (typically 18-30 inches) with maximum color saturation. All leaf coloration is vivid and fully developed. Foliage is densely packed and ornamentally stunning.

Begin harvesting outer leaves regularly to encourage continued growth and maintain plant shape. Continue regular watering and monthly fertilization. Monitor for pests and adjust light if needed.

Flowering & Seed Production

3-4 weeks

Tall inflorescences develop at the top of the plant with small, densely packed flowers. Seed heads form and gradually mature, becoming heavier and darker.

If saving seeds, allow flower spikes to mature fully on the plant. For continuous leaf harvesting, pinch off flower buds to redirect energy back to foliage. Reduce watering slightly as flowering begins.

Harvest & End of Season

2+ weeks until frost

Mature seeds are ready for collection if allowed to flower. Leaves remain edible throughout but may become tougher. Plant begins to decline as temperatures cool (below 60°F) or after first frost.

Harvest seed heads by cutting and drying indoors. Continue harvesting leaves until frost. Allow a few plants to self-seed for next season if desired. Clean up plant material once killed by frost.

Companion Planting

Plan your garden →

Plant with:

basil marigold nasturtium zinnias beans peas cucumber squash

Avoid planting near:

fennel walnut trees

Common Pests

Increase humidity and spray with water; use neem oil or insecticidal soap if severe. Remove heavily infested leaves.
Spray with strong water stream; apply insecticidal soap or neem oil. Encourage beneficial insects like ladybugs.
Hand-pick visible caterpillars; use Bacillus thuringiensis (Bt) if needed. Row covers protect young plants.
and
Remove by hand, especially at night. Use diatomaceous earth or copper tape barriers. Keep area dry.
Use row covers on seedlings. Apply neem oil or spinosad for older plants. Remove heavily damaged leaves.

Uses

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Nutritious leafy green

Culinary

Tricolor Amaranthus leaves are edible and highly nutritious, rich in vitamins A, C, and K, plus minerals like iron, magnesium, and calcium. Young tender leaves can be eaten raw in salads or cooked like spinach in stir-fries, curries, and soups. [source]

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Grain & seeds

Culinary

The small seeds produced by mature plants are gluten-free grains rich in complete protein and amino acids. Seeds can be popped like popcorn, ground into flour, or cooked as a porridge, and are valued in traditional cuisines worldwide. [source]

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Garden ornament & landscape accent

Ornamental

The brilliant tricolor foliage of 'Illumina' makes it an outstanding focal point or accent plant in borders, containers, and mixed beds. Its vivid reds, golds, and greens add dynamic color contrast and visual interest to garden designs. [source]

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Traditional remedy plant

Medicinal

Amaranthus species have been used in traditional medicine systems, particularly in Indian and Ayurvedic practices, for digestive health and anti-inflammatory properties. Leaf teas and preparations are believed to support digestion and overall wellness. [source]

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Bird and pollinator food source

Wildlife

Mature seed heads attract a variety of birds and beneficial insects including finches and pollinators. Leaving some seed heads standing provides a valuable late-season food source for wildlife before winter. [source]

This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.

Harvest Tips

Begin harvesting outer leaves once plants are 8-10 inches tall; this promotes bushier growth and continuous production. Pinch off top 2-3 inches of stems regularly for tender young foliage. For best flavor and nutrition, harvest leaves in the morning after dew dries. Mature leaves can be harvested throughout the season until frost. If saving seeds, allow flower heads to fully mature and dry on the plant, then cut and hang to finish drying indoors before storing in a cool, dry place.

Fun Facts

🌱 Amaranthus was a staple crop of the Aztec civilization, valued as highly as corn and beans, and held sacred significance in religious ceremonies.
🌱 The name 'Illumina' refers to the plant's striking luminous appearance when backlit by sunlight, with the leaf colors glowing brilliantly.
🌱 Amaranthus is one of the few plant species that can thrive in diverse climates from sea level to high altitude, and it's also drought-tolerant enough to be considered a crop for food security in marginal environments.

Gardening Terms

New to gardening? Learn about terms used in this guide:

Cultivar Full Sun True Leaves

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