do you need two passion fruit vines to get fruit and how long does it take to get fruit eg more than one fruit

Passionfruit are self-fertile, so there is no need to have two vines. We recommend you look at planting grafted varieties, as they're hardier and can be more productive. Ensure you feed with a fertiliser high in potassium in mid-spring to encourage flower and fruit set. 

Try Yates Thrive Flower & Fruit Soluble Plant Food: