A long time ago my island was overrun with hybrids, I tried multiple times to sell them in the Nooks Cranny section on Bell Tree Forums and on the discord server but only a few people wanted them :/ I ended up selling all of my hybrids to the shop, though I saved 5 hybrids of each type.
I refuse to spend any type of currency on buying hybrids (or taking them from someone for free) because I have this mentality that if it's realistically achievable in my game, I HAVE to do it myself. This also inhibits me from ever buying someone's DIYs because I KNOW I can get them myself with a bit of luck and patience. I always lurk on threads in Nook's Cranny and see all these things I'd like to buy and then I see the prices and I'm like "Can I really justify dropping 10TBT on a bonsai shelf when I'd probably be walking through my cranky's door tomorrow and have him give it to me?" Whatever, I'm extremely frugal (and also going off-topic)
That being said, I only have blue roses and orange hyacinths to go, so it's not like it is hard to do
I see a LOT of people trying to get rid of their hybrids in the Nook's Cranny-subforum though, at least five threads a day, oftentimes for free, but just a week ago I've also seen them go for TBT. I myself needed to actually physically prevent my flowers from spawning inbetween my stepping stones pattern, so I actually sacrificed a custom design slot for a completely transparent pattern (which hurt way more than it should've, Nintendo f****ing increase the slots goddamnit) and put it inbetween the stones. That way, I'll never have to worry about excess flowers again and it can rain and snow on my island all day long
Also, you can "store" up to 80 flowers in your recycle bin using the co-op feature. I use this to keep the flowers I cycle out with the seasons, because I have seasonal areas that I change up every once in a while
I think they were being traded a lot when the game first came out, because people wanted the ones that were not native to their island. Though personally, after all the rain from June, I had way too many I didn't know what to do with. I've tried giveaways but it seems most people also have a flower problem at this point lmaoo
Due to the breeding limit removed and the cloning mechanic added, Hybrids are no longer 'rare'. The only valuable ones are the complex hybrids like Blue Roses and Purple Windflowers - but once you get at least a dozen of everything, it's easy to have too many of them.
Another thing is with the introduction of furniture, flowers in general have entered the backseat in decorating. In New Leaf, flowers were the big part of decor, as there was a huge limit in what you could decorate outdoors. Now you can develop large attractions with just furniture and terraforming alone, then just put maybe a couple select flowers here and there afterwards. Plus, with a much larger selection and coloring in New Horizons, it requires us to be more selective about the flowers we use - which makes them even more niche.
I myself have an excess number of Orange and Purple roses after breeding my first Blue roses from scratch. And I dare say I may have to sell a huge amount of them to the Nookings, as I don't think anyone will want them on this forum - Even if I give them away.
I know there used to be a market (if I remember correctly) when the game was still relatively new, though nowadays, it’s hard to give away any hybrids, let alone sell them. I guess people have just played enough that they are at the point that they have their islands overrun as well! I personally still like picking up a couple hybrids (mainly from my sister’s island) if I’m too lazy trying to breed more, etc., as I haven’t really done much with flowers other than decorating when I have a couple that I like. Right now, all of my flowers are on my beaches, until I’m ready to start using them for decoration (I recently flattened out my island to redecorate and terraform with a new theme!)
i gave away a bunch of hybrids i didn't need. the rest i store on my beach but i'll have to clear it out at some point soon because it's getting overly full
I think it used to be a big thing when the game first came out and a month or two after - I definitely bought quite a lot of hybrids here and even sold a couple too. These days I don’t think that hybrids have that much value though and personally I just sell them to nooks or just trash them. I guess there are still some people who trade for it but I don’t see much demand for them anymore.