Eden Brothers
Cosmos Seeds - Radiance
Best low-maintenance annual for beginner gardeners seeking vibrant pollinator-friendly blooms.
Cosmos 'Radiance' seeds offer the beloved classic cosmos with stunning, deep wine-red petals and bright yellow centers. These easy-to-grow annuals reach 3 to 5 feet tall, providing a spectacular display from mid-summer through fall. Perfect for novice gardeners, they add vibrant color to any landscape, container garden, or cut flower arrangement. Radiance Cosmos are also a magnet for pollinators, attracting bees, butterflies, and hummingbirds, making them a beautiful and beneficial addition to your garden.
$5.49
Owner Satisfaction
4.7
/ 5
Category Rank
270
/ 5876
#270 in Seeds & Seed Tape
Price vs Category Average
-48%
Below average
Botanical Name
Cosmos bipinnatus
/ Cosmos bipinnatus
Who it's for
- Novice gardeners seeking reliable, quick-starting blooms
- Landscape planners wanting long-lasting seasonal color
- Eco-conscious gardeners supporting local pollinator populations
Who should skip it
- Gardeners avoiding the extra labor of staking tall plants
- Owners of highly fertile soil seeking maximum flower yield
- Low-maintenance gardeners wanting to avoid aggressive self-seeding
Performance breakdown
Gardening Accessibility
Simple growth requirements make these ideal for absolute beginners.
Pollinator Attraction
High-impact blooms effectively draw bees, butterflies, and hummingbirds.
Environmental Resilience
Thrives in poor soil and withstands heat and drought conditions.
Bloom Longevity
Provides a consistent, vibrant display from mid-summer through autumn.
Versatility
Adapts perfectly to both container gardens and cut flower arrangements.
Pest Resistance
Naturally deters deer, minimizing the need for protective garden measures.
Key Specs
Botanical Name
Cosmos bipinnatus
Seed Type
Open Pollinated Seed
Plant Height
44 to 60 inches
Planting Depth
1/4 inch
Plant Spacing
9 to 12 inches
Days to Maturity
60 to 90 days
Hardiness Zones
2 through 10
Growth Habit
Clumping
Features
- Mesmerizing glossy pink blooms with yellow centers
- Easy-to-grow annual for long-lasting summer blooms
- Attracts bees, butterflies, and hummingbirds
- Tolerant of heat, drought, and poor soil
- Deer resistant for worry-free enjoyment
- Ideal for container gardens and cut flowers
- Fast-growing with an extended bloom period
What customers say
Customers consistently praise the exceptional quality of the Radiance Cosmos seeds, noting remarkable germination rates that lead to lush, vibrant displays. Gardeners frequently highlight the ease of use, emphasizing that even novice planters achieve beautiful results quickly. The seeds reliably produce the promised mix of colors, making them a highly satisfying and dependable choice for adding effortless beauty to any garden space. This consistent performance establishes a strong sense of trust in the Eden Brothers brand.
Know before you buy
These plants typically reach between 44 and 60 inches in height. Because they grow quite tall, you may want to place them toward the back of a garden bed or provide support if your area is prone to high winds.
Yes, they are container-friendly. Ensure your pot is large enough to support their height and has adequate drainage, as they prefer well-drained soil.
For the best results, plant them in a location that receives full sun to partial sun. While they are heat and drought tolerant, consistent sunlight is key to achieving their full bloom potential from mid-summer through fall.
Yes, Radiance Cosmos are generally considered deer resistant. While no plant is entirely immune to hungry wildlife, these are a great choice if you have had issues with deer browsing in your garden.
You can expect the plants to reach maturity and begin blooming within 60 to 90 days after planting. They are fast-growing annuals that provide a long-lasting display throughout the summer and into the fall.
These cosmos are very adaptable and actually perform well in poor soil, so you do not need to worry about heavy soil amendments. Simply plant the seeds at a depth of 1/4 inch and space them 9 to 12 inches apart.
Still have a question?
Ask Hayley anything about this product before you decide.