Answer: Although I am not certain which cosmos you are growing, there are several possible explanations. It may be that this variety needs a longer growing season because it simply requires more maturity to bloom than the other cosmos we normally grow as annuals. This might explain why it is rare. It may simply be a shy bloomer, which again would explain why it is rare. It may be that it has too little light or too much nitrogen (this will cause lots of foliage and fewer blooms). It may be that it is actually a perennial variety of cosmos and will not bloom until next year. If you have the space, you might leave them there and just wait and see what happens.
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