Cosmos flowers, with their origins in Mexico and South America, are a cherished addition to gardens across the United States for their striking daisy-like flowers and ability to attract pollinators. Among the various species, Cosmos bipinnatus and Cosmos sulphureus are the most commonly cultivated.
**Cosmos bipinnatus** is known for its large, daisy-like flowers, which can range in color from pink and purple to red and white, often featuring a distinctive yellow center. The foliage is feathery, and the plant can reach several feet tall. Within this species, there are taller varieties, perfect for creating a backdrop in garden beds. The ‘Chocolate Cosmos’ is a unique variety originating from South America, famous for its deep, almost chocolate-colored flowers and a faint chocolate scent.
**Cosmos sulphureus**, or "Yellow Cosmos," has smaller, compact flowers in shades of yellow, orange, and red, and typically grows less tall than C. bipinnatus. This species is known for its broader leaves and shorter stature, usually reaching a few inches tall.
Growing cosmos is relatively straightforward. They thrive in full sun and well-drained soil, though they can tolerate poor soil conditions. However, for optimal growth and flowering, planting them in rich soil can be beneficial. These plants are drought-tolerant but keeping the soil moist, especially during dry spells, will ensure healthier plants. They can grow quite tall, with some varieties reaching several feet in height, so providing support might be necessary for taller varieties.
To start cosmos flowers, you can sow seeds indoors before the last frost date, ensuring that the danger of frost has passed before transplanting them outside. This head start allows the plants to establish themselves and begin blooming earlier in the season.
One challenge cosmos gardeners may face is powdery mildew, especially in humid conditions or when the plants are too closely spaced, reducing air circulation. To mitigate this, ensure adequate spacing between plants and consider varieties that are resistant to powdery mildew.
Cosmos flowers, with their diverse range from the tall, feathery Cosmos bipinnatus to the shorter, vibrant Cosmos sulphureus, are an excellent choice for gardeners in the United States. They not only add beauty and height to gardens but also play a crucial role in supporting local ecosystems by attracting various pollinators. Their easy cultivation and care make them a favorite among both novice and experienced gardeners.
All of our Cosmos flower seeds are open pollinated, meaning they have been pollinated by insects, birds, wind, or other natural mechanisms.