Packet of about 300 sensation mix flower seeds.
- Sow seeds lightly—about ¼-inch deep and 12–18 inches apart after the danger of frost has passed. You can also plant transplants instead of seeds.
- Cosmos don’t need any special soil preparation. In fact, they like soil that is not too rich, as rich soil will encourage foliage at the expense of bloom.
- Cosmos flowers can tolerate warm, dry weather. They are even drought-tolerant.
- Depending on the type of flower, cosmos can grow anywhere between 18 to 60 inches tall.
- If you are growing cosmos from seeds, be mindful that it takes about 7 weeks to first bloom. After that, though, your flowers should continue to bloom until the next frost.
- If you want a head start, you can plant cosmos indoors 4 to 6 weeks before the last spring frost in trays or pots with a good seed-starting mixture. Move them into 5-inch pots as soon as they’re 3 or 4 inches tall.
- If you let the spiky-brown seed heads blow away during the fall, cosmos might self-sow throughout your garden.