Apps or websites that guide me on floral decor.

As I posted in my previous discussions I have decided to for DIY floral decor for my wedding. Some helpful people suggested me to order from Fifty flowers and also shared their experience. However, I am still confused about whether the kind of flowers I want will be available in January next year or not. I know I can research and everything but I still don't know if those flowers will be available online for a cheap price in my area. I want to know my options for January right now and book them accordingly. If I decide and book flowers right now I wouldn't be stressed about them at the time of my wedding. But it seems like I know really few apps or websites that allow me long term planning. Have other DIY brides faced the same problem? Does anyone know any apps or websites that can help me with this?