Sulphur Cosmos, Dwarf Orange (Cosmos sulphureus) Annual Flowers Seed
Approx 4,500 seeds per oz
Add colorful texture to any bouquet.
Great for the garden or container!
Sulphur Cosmos is native to Central and South America. Our dwarf varieties grow to just 18-24 inches tall and make great additions to beds and borders. Also recommended for mass plantings, low-growing mixes, and the pollinator garden.
Cosmos flowers can be successfully grown in containers. Species plants can grow as much as 6 feet tall, so look for dwarf or compact cultivars for containers.
If you’re looking for container plants loaded with pretty blossoms throughout summer and well into fall, cosmos is a great choice. Growing cosmos in pots is easy and you’ll be rewarded with plenty of flowers for cut or dried arrangements, or you can simply enjoy them in their pot. Keep reading to learn more about container grown cosmos.
How to Grow Cosmos in a Pot Choose a pot at least 12 inches in diameter with several drainage holes in the bottom. Heavy pots are stable and can help prevent the plant from toppling. If you use a lightweight plastic pot, place a layer of gravel in the bottom of the pot to add weight before filling it with potting mix. Scatter the seeds thinly over the surface of the potting soil and cover them with one-third to one-half inch of additional soil. When the seedlings are 4 inches tall, thin the plants by clipping out the unwanted seedlings with scissors. Container-grown cosmos looks best when you thin the plants to about half the distance recommended on the seed packet. When your seedlings are off to a good start, set the pot in a sunny location. Water container-grown cosmos when the soil is dry to a depth of two inches. Drench the soil and then allow the excess water to drain through. After about 20 minutes, empty the saucer under the pot. Cosmos doesn’t like excess moisture and the roots may rot if the pot is left sitting in a saucer of water. Pots that sit in sunny locations dry out quickly, so check the soil moisture daily. Cosmos plants react to rich, fertile soil or an abundance of fertilizer by growing tall and leggy. When growing cosmos in pots, a light feeding with slow-release fertilizer lasts through the entire season. If you prefer, you can use a liquid fertilizer mixed at one-quarter strength once every week or two. If the plants start to look lanky, cut back on the amount of fertilizer. Pinch off dried leaves and faded flowers to keep the pot looking neat. Regular deadheading encourages the plant to produce more blossoms. If the stems become leggy with few flowers in mid-summer, cut them down to about one-third of their height and let them regrow.
Cosmos are native to Mexico and require full sun. Cosmos work well as cut flowers and are good container plants. The Cosmos seed is a popular source of food for birds. Cosmos do not like extremely rich soil, if fertilized they will often grow too tall and not be able to stabilize themselves. Planting Cosmos and watering them until they are established will yield the highest quality plant. Once they are established they do not need nearly as much water. These flowers thrive in warm weather and in turn do not tolerate cold or wintry climates.
Directly sow Cosmos Mexican Aster flower seeds into prepared seed beds after danger of frost has passed. Sow the Cosmos flower seeds in rows, 18 inches apart. Sow 6 seeds per foot. Lightly cover Cosmos seeds with 1/16 inch of soil. Keep flower seeds moist. Thin to strongest plant 12 inches apart. Or, if you're not into measurements, Cosmos flower seeds can be scattered onto the prepared soil. Lightly rake the soil over the Cosmos seeds at a depth of 1/16 inch. Keep the Cosmos flower seed moist until germination. They perform well even when crowded.
USDA Zones: 3 - 10
Height: 36 - 48 inches
Bloom Season: Summer and fall
Bloom Color mix
Environment: Full sun to partial shade
Soil Type: Well-drained, pH 6.1 - 7.4
Temperature: 70 - 85F
Average Germ Time: 14 - 21 days
Light Required: Yes
Depth: 1/16 inch
Sowing Rate: 6 seeds per plant
Moisture: Keep seeds moist until germination
Plant Spacing: 12 - 18 inches
Important, Please Read
All seeds have been test sown to ensure germination. Please familiarize yourself with growing conditions and instructions for your seeds before you plant them, as all seeds are different. Basic growing instructions can be found in detail section of each listing.
We Cannot Guarantee how much you will be able to grow, as too many variables come into play, soil condition, your ability to garden, weather etc. I guarantee that they arrive as described and are in good viable condition and the germination rates are accurate.