With the magnificent plants, trees and flowers we have to show off, no wonder New Yorkers get euphoric come spring! Here’s what’s in bloom: Thru Apr. 4, you can see jaw-dropping arrangements of flowers from around the world at the Macy’s Herald Square Flower Show. At The New York Botanical Garden’s Orchid Show (thru Apr. 19), dozens of orchid species hang from the ceiling, including a star-shaped chandelier. And at the Brooklyn Botanic Garden, you can now view the recently planted Native Flora Garden expansion, with cultivated pine barrens and a meadow modeled after Long Island’s Hempstead Plains.