Ugly plants and trees. You see them at even at the nicest of sims, and put out by people who normally have excellent taste in decor. It’s not that the species of plants are ugly, it’s that the things just do not look like plants at all.
Ok, they do look pretty if you view them from a distance or from a certain angle. Then they’re fine. But if you move your camera around, they look like cardboard cutouts stuck together in a circle.
Here’s an example of some trees from a distance. All ok, right?

Well, here’s what they look like if you cam near and don’t look at them directly from the front.

Originally plants were made like this to save prims. In the old days if you made something like a rose bush or tree that looked realistic from every angle, the prim count would be through the roof. So people accepted the cardboard trees to decorate because it makes more sense prim-wise.
Guess what? I found a place with plants that look great from every angle. No cardboard. No standups glued together passed off as plants. Not only that but almost everything there was just — you ready for this? — ONE PRIM. Unfortunately I didn’t see any big trees there, but you will find flowers and potted plants, among other things.
Here’s an example of some flowers. Yes, they looked this good at every camera angle. Yes, they are just one prim per pot of flowers!

These are mesh plants created by XED. They are copiable and reasonably priced. Seeing them has made me like mesh just a little bit more.
Visit Inworld: XED Design


In case you haven’t seen them yet, they’re not mesh and a little on the small side, but Fiddler’s Green sells some pretty nice 2 & 3 prim trees on MP for L$39 (free demo too): https://marketplace.secondlife.com/stores/82907
That is surely a better alternative than using cardboard plants.