Okay... Let me say this: Blue Roses are stupid hard to breed from scratch. That said, let me give some tips:
-When getting hybrid reds, try only using Orange Roses that were bred from other orange roses, and Purple roses from other purples.
-Any red roses you get from the hybrid reds may not necessarily be hybrid reds themselves, so move them away from the garden.
-Try to get at least 12 Hybrid reds to breed with, and spread them out in a checkerboard circle. That way, you'll get extra chances that a Blue will spawn.
-Use the beach to breed them, or on a place where villagers won't try to walk on them.
-If you use fertilizer, dig and bury it in a fashion that does not 'push' a rose down. I theorize that pushing a flower induces stress that prevents the hybrid process.
-The Gold Shovel is your best bet to make them spawn. Only when I got that item did I ever get a blue.
-Make sure you only water the hybrid reds, and no other flower.
Hopefully this helps. Understand that Hybrid Reds can create every rose color except gold ones, and that Blue Ones are rare to get from them.
