to increase chances of getting hybrids? i'm thinking of moving them to the beach, but that'll take a while. i might wipe out most of the cosmos and pansies because those don't look nice, neither do the lilies.
i was thinking of doing the same thing, but it'd be a lot of work x__x but worth it?? idk i say move your flowers to the beach first and try and organise your hybrids in a pattern that would increase their fertility and see how it looks over the next few days. if you're happy with the design, trample/sell your common flowers. otherwise, if you're not getting much results and it looks a bit plainer, you can just take them back up to the high land!! B)
If you don't have beautiful town ordinance, when the flowers wilt and you pick them, it counts towards your weeds pulled. You could keep them around and slowly pick them off when they wilt.
I usually just throw them away if they become too many. One of my houses has a trash can in it, so I use that. Actually killing them by running over them takes a lot of work... and grass wear. :C
One reason I reset my old town was because I was flooded with flowers. It sounds awesome but it's really not. Not even hybrids, just regular flowers. I don't even water them, they just grow. And villagers kept planting new ones. It got to the point where there was nothing I could do about it, that almost every walking space on my town is flowers (it's insanely pretty, but I needed my running space, y'know), and that it took me two characters and a full storage of both to save even only the hybrids.
Flower infestation. Who knew? Don't let it happen to you.
If you still want them just put them all mixed up and in an unbreedable (?) pattern- that way you won't have to sell all of them and you'll still have them later.