Ornamental
Red Spike Amaranth is a striking annual flower that delivers deep crimson plumes perfect for late summer and fall arrangements. This upright variety reaches maturity in 45 to 70 days and stays structurally sound once cut, with feathery flower spikes that retain movement and visual interest in bouquets. Beyond its ornamental appeal, the tender leaves are entirely edible, offering a nutritious green vegetable when harvested before full maturity. Thriving in full sun and adaptable to container growing, this amaranth bridges the line between flower garden and kitchen garden.
12-18 inches apart
Full Sun
Moderate
2-11
?in H x ?in W
Annual
High
Hover over chart points for details
The deep red coloring is precisely what you want for late-season arrangements; the upright growth habit means the flower spikes stay elegantly positioned in the vase rather than drooping. Unlike purely ornamental amaranths, Red Spike pulls double duty as a leafy green, with young foliage that's both tasty and nutrient-dense when picked early in the plant's development. The feathery plumes retain movement and dimension even after cutting, adding architectural interest that stiff, static flowers simply cannot match.
Red Spike Amaranth shines as a cut flower for late-summer and fall arrangements, where the deep red spikes and feathery texture add drama and movement to mixed bouquets. The tender young leaves work as a cooked green, similar to spinach or chard, offering a mild, slightly earthy flavor when prepared before the plant reaches full maturity. Home gardeners often harvest the foliage for fresh greens while allowing the plant to continue developing its ornamental flower spikes.
Start seeds indoors 4 to 6 weeks before your last expected frost date. Sow seeds 1/4 inch deep in moist seed-starting mix and maintain soil temperature between 70 and 85 degrees Fahrenheit for consistent germination. Provide bright light once seedlings emerge, as amaranth prefers strong illumination.
Transplant seedlings outdoors after the last frost date when soil has warmed to at least 60 degrees Fahrenheit, ideally 65 to 75 degrees. Harden off seedlings by gradually exposing them to outdoor conditions over 7 to 10 days. Space transplants 12 to 18 inches apart in full sun.
Direct sow seeds outdoors after all frost danger has passed and soil temperature reaches at least 60 degrees Fahrenheit. Sow seeds thinly and cover lightly with soil, pressing gently to ensure good seed-to-soil contact. Keep soil moist until seedlings are established.
For leaf harvesting, pick tender young foliage before the plant reaches full maturity and the leaves become tougher and more fibrous. Typically this window occurs 20 to 30 days after germination, when leaves are still pliable and mild in flavor. For cut flowers, harvest the deep red spikes once they have fully developed color and the feathery plumes are fully extended; cutting in the early morning when stems are hydrated ensures the longest vase life. Stems will remain upright and retain their feathery movement for weeks in a vase with fresh water.
No pruning is necessary for Red Spike Amaranth. The upright growth habit naturally produces a single, strong central stem with minimal branching. If harvesting leaves, pinch or cut tender foliage from the lower portions of the plant before the flower spike fully develops, which encourages bushier growth and extends the leafy harvest period.
Enter your ZIP code to see a personalized growing calendar for this plant.