Q.bittersweet vine
First, I purchased a bittersweet vine, don’t know if female or male, then discovered you need both. My bittersweet vine produces nothing but foliage, lots of leave, is that normal? It is only about a year old. If I purchased the opposite sex, would that improve? Things in my yard wisteria etc, among other plants produce much foliage, little flowering, is this too much nitrogen in the soil? Could you please advise me? Thank you Rhonda Galvin
Unless you purchased both a male and female plant; they should be labeled by the nursery; there is no way to know what you have.
It can take years for a vine to establish and produce berries. I'm in a cold climate and just have my first crop of berries, 9 years in!
https://www.gardeningknowhow.com/ornamental/vines/bittersweet/growing-bittersweet-vines.htm
A soil test will help you determine the nitrogen levels in your soil. In general excessive nitrogen inhibits flowering.
Your County Extension Office can help with a soil test.