Simply collect pollin from the male flowers that are ready to shed their pollin and brush the pollin on the female flowers. If there are no female flowers you might try saving pollin till the following morning when more blooms open.

Where I am the best time seems to be late afternoon.
Hope that helps.

I planted my tree last year. It was appx 2.5 ft talk. It is now over 8ft tall. I feel it should be ready to bloom soon. Any ideas on how to make this happen? Maybe some more potassium? It is growing so fast. My other annonas are 3yrs old, that is sugar apple and custard apple and atemoya. My Rollinia has out grown them all in just one year.

I planted my tree last year. It was appx 2.5 ft talk. It is now over 8ft tall. I feel it should be ready to bloom soon. Any ideas on how to make this happen? Maybe some more potassium? It is growing so fast. My other annonas are 3yrs old, that is sugar apple and custard apple and atemoya. My Rollinia has out grown them all in just one year.