I love the botanical gardens. The theme is changed about four times a year and is currently a spring theme with watering cans, frogs made out of flowers and giant, scary ants. It's all good, though, and there are plenty of photo opportunities. You may have to take turns with [other] tourists if it's busy, so go in the morning. It's open all the time.
Since I live in Vegas now, I visit regularly and it's always impressive. How DO they make so many things out of beautiful flowers and keep them in pristine condition?