Ornamental Annual
Red Flint Ageratum rewrites the script on this beloved cottage garden flower with blooms in reddish, berry tones that evoke boysenberry jam and ripe plum, a striking departure from the soft blues gardeners typically expect. This taller heirloom variety reaches about 24 inches, making it substantial enough to anchor beds, borders, and cut flower arrangements with presence and drama. Flowering in 85 to 90 days from seed, it thrives in full sun and rewards patient growers with those exquisite, unexpected blooms that seem almost jewel-toned against the fine foliage.
9-12 inches apart
Full Sun
Moderate
10-11
?in H x ?in W
Annual
Moderate
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Red Flint Ageratum stands apart for its dramatic departure from the pale blues and pinks that dominate the ageratum world. The flowers exist in a rare color space between boysenberry jam and plum, a deep, complex red tone that catches light and draws the eye in any garden setting. At 24 inches tall, this heirloom is considerably more imposing than dwarf modern hybrids, making it work beautifully as a landscape feature rather than just a filler plant. Whether massed in beds or brought indoors for arrangements, this variety brings sophistication and unexpected color to cottage gardens, borders, and cut flower displays.
Red Flint Ageratum shines in ornamental applications where its striking color and substantial height can be fully appreciated. The flowers are prized for cutting, bringing those jewel-toned blooms into indoor arrangements where the unusual berry-plum coloration becomes a conversation piece. In landscape design, the variety works beautifully massed in beds and borders, as a backdrop plant that adds depth and visual interest, and as a cottage garden centerpiece where its height and uncommon coloring command attention among companion plantings.
Surface sow seeds indoors under warm conditions and expect germination in 7 to 10 days. Maintain soil temperature around 75 to 80 degrees Fahrenheit for optimal sprouting. Begin seeds indoors 6 to 8 weeks before your last frost date to have flowering-sized transplants ready for the garden.
Transplant outdoors after all danger of frost has passed and soil has warmed. Harden off seedlings gradually over a week before moving them to their final location. Space plants 9 to 12 inches apart in full sun.
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“Red Flint Ageratum represents a preservation of heirloom genetics within Ageratum houstonianum, the species native to Mexico. As a heirloom cultivar, it carries forward the classic cottage garden tradition of this beloved flower while expressing genetics that produce those distinctive reddish, berry-toned blooms, a phenotype far less common than the standard blue and pink varieties that came to dominate the ornamental seed trade. The variety's existence today speaks to seed savers and heirloom gardeners who maintained it when commercial breeding moved toward more uniform, compact modern hybrids.”