I have Astrophytum Asterias grafted on Selinicereus, last summer its produced something neither flower bud nor offset , its remains small and green (you still can see it in the picture) this year its started a flower bud for the first time but it fall before blooming , any idea about the reason / solution? thanks.
This is the incomplete bud..
Cactus don't bloom!
Cactus don't bloom!
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