Think about its natural growing environment. For some den's to flower you need to restrict the water for a period. This could be up to 11 weeks. Others in my collection that have proven to be stubborn I have mixed up a weak solution of Epson salts two doses about a week apart has worked for me. Looks a nice healthy plant. Whats its name. I also had a den that took 7 years to flower now it won't stop.