Cosmos sulphureus Seeds (Lemon Sulfur Cosmos)

Lemon Sulfur Cosmos, also known as Cosmos sulphureus, is a vibrant annual plant that adds a burst of color to gardens and landscapes. With its attractive lemon-yellow flowers, it blooms profusely from summer to fall, attracting bees and butterflies with its nectar-rich blossoms. This plant is relatively low maintenance and can reach a height of 2-4 feet. It is suitable for USDA hardiness zones 9 to 11 and can be easily grown from Cosmos sulphureus seeds. Whether in borders or containers, Lemon Sulfur Cosmos brings a cheerful touch to any garden with its striking yellow blooms.

Growing Cosmos sulphureus from Seed

• Growth cycle: Annual
• Watering: Medium
• Sunlight: Full Sun
• Suitable climates: Tropical Wet, Tropical Wet & Dry, Arid, Semiarid
• Where to grow: Outdoors
• Flower color: Orange

Germinating Lemon Sulfur Cosmos Flower Seeds

To germinate Cosmos sulphureus, sow the seeds in well-drained soil and lightly cover them. Maintain a temperature of 70-80°F (21-27°C) and provide indirect sunlight. Keep the soil moist but not waterlogged, and seedlings should emerge within 7-14 days.

We source all of our Cosmos sulphureus seeds from a small greenhouse facility based in southeastern Maine and store them in a dark, temperature-controlled environment before shipment. You’ll find that our fresh Lemon Sulfur Cosmos seeds are much easier to germinate than the mass-produced packets of flower seeds found in stores! If you have any trouble growing Lemon Sulfur Cosmos seeds, we’re happy to send you additional gardening tips. In the (unlikely) event that your Cosmos sulphureus seeds do not germinate at all, we’ll give you a full refund, no questions asked.

We offer this variety on Etsy and eBay, as well!

Shipping & returns

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