Cosmos Dwarf Sensation Mixed Seeds

Yes, you can either scatter cosmos seeds outside or grow them indoors before transplanting outside. They may germinate in as little as a week after planting.

Cosmos grow tall with no flowers for multiple reasons: it may be that yours has too much shade, which encourages vegetative growth; or, that it has too much nitrogen in its soil mix. This is also known as “stretching”. You can encourage it to bloom rather than produce leafy growth by pinching back its stems or, if the problem is persistent, replanting it somewhere more appropriate.

No: you don’t need to do anything special to your cosmos seeds before planting them. No soaking, stratification, germination, or anything else is necessary. Just plant them and watch them grow!