Nick Nelson designs all of the short- and long-term exhibits at the Botanic Garden. (Allie Caren for Express)

Much of the same planning that goes into a building’s architecture applies to a garden’s architecture, especially one as large and detailed as the fragrant, pleasantly humid, lush-as-can-be United States Botanic Garden. Though there is one obvious difference.

“A garden can mature and evolve in a way that a building cannot,” says Nick Nelson, the botanic garden’s landscape architect.

That and, well, plants die.

While a staff of horticulturists maintain and manicure the botanic garden, Nelson spends the majority of his days in his office planning for his next project, like the annual holiday display or orchid show. He often starts his concept drawings with pen and paper, and eventually switches to a computerized 3-D drawing tool for more detail.

“I still do love the power of a hand sketch and a hand-drawn perspective,” he says. “Even though I’m not selling anything, I still need to sell people on my idea.”

Though his mother was an avid gardener, it was high school golf that first piqued Nelson’s interest in turf management and design. That, plus his artistic ability, ultimately led him to study landscape architecture in college. It wasn’t until his career began at Pennsylvania’s Longwood Gardens that he started to have more of an appreciation for plants. Since he got the landscape architect gig at the U.S. Botanic Garden in 2008, he has developed all of the short- and long-term projects at the botanic garden. His favorite was designing the 16-foot urn that sits in front of the garden — a space that was originally going to be occupied by a large water feature. “We decided: we’re a garden, so let’s do a giant planter,” he says.

Nelson takes a lot of pride in those types of permanent projects; the plants and exhibits that will be around for visitors to see for years. Though, given that he’s working with living things, he adds, “Nothing’s ever permanent here, that’s for sure.”

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