Can someone please tell me the name of this plant and what its needs as far as sun & water?

Thanks

It's an oxalis. I was given some last year and planted it in several places outside...it survived hurricane Michael and my winter and has come back in both sun and shade for me. Although I'm in Florida, here in the panhandle we do get freezes in winter.

Oxalis triangularis Purple Shamrock (Oxalis triangularis)

I agree, Purple Shamrock. I've never grown it as an indoor houseplant but I do have it in container plants that stay outdoors year round here in my Florida garden. They require bright, indirect light (no direct sun) and moist but not soggy soil. If the soil stays too wet, the underground rhizomes will rot. My plants go dormant at times but they usually do reappear again at some point.

Oxalis can be grown successfully indoors if it is kept close to a moderately sunny window where it will get a couple of hours of direct sun each day. Allow the top half-inch of soil to dry before watering.

Older lower leaf stems tend to droop as they age. They can be cut off at any time. Excessive dryness will cause it to go into dormancy as Lin described.

Oxalis is a favored host of spider mites so be alert for them.

Grows very reliably in the ground over here too. I have mine in part shade. I set the sprinkler for twice a week.

I have mine (it's a slightly different variety) in morning sun on my patio for years now. Seems like it would be a delicate plant but it's actually one tough plant!

I don't have triangularis, but have plenty of other Oxalis ( bird planted) in my lawn and flowerbeds.

I have it growing in my yard. Its on the south side of my house under a bush. I am surprised it has survived as my winter lows are usually around 10 degrees.