It may be infertile, needing a bee and pollination to flower. It may just be a genetic 'lemon'. It may require very specific temperatures and lighting at specific times. Have you done any research?

This is my research. I have read a lot online about them, but nothing talks about them flowering or not flowering. The closest I have come is "more sunlight promotes more flowering". But in so many cases I get the best counsel from people who actually grow the specie in question so I was hoping the forum would help me find such a one.

Hello Winter jasmine. "jasminum nudiflorum" This bonzai needs to be kept alomost frozen durning winter . and would enjoy it.. What usually happens is in the winter when u get a warm spell "32f," is when the tree will flower. it only flowers in winter lol...its a hardy plant. minum temp is 15f it flowers at 32f-38. does not like prolonged exposure to sun when tepts are constantly above. 86f. hope it helps lol..
P.S they dont need bee,s lol

Thank you - that helps. Perhaps I did not let it get cold enough. I know it was below freezing on many nights, but maybe not enough of them....

I am new to Bonsai but bought a 1 gal. potted plant on sale last fall. It looked dead. I put the pot in the ground next to the house with a little mulch around the base of the plant and left it there all winter. It has been down to minus 2 or 3 F. here this winter with snow on and off. It has just bloomed for nearly three weeks and we had it in the house on and off.