Is March a good time to visit to see blooms?

I think it would be better if you plan around mid-April. They are running reconstruction and I think they are targeting a larger opening for summer. So, I suggest you postpone until April or even May.

Every plant is not in full bloom but there is plenty to see especially if you go see the orchids. There's a rainforest and desert area with lots of plants to learn about.

Yes!

No

I'd wait til late April for blooms

There are a couple of exhibits open now but if you are looking to stroll through the entire grounds, April is better. Some display were undergoing reconstruction (late February -March).