There's a lot of technical drawing and CAD, but that's just the final stages of a project after all the fun drawing and research. With your degree you could easily go the professional horticulturist route as-is or jump into an MLA bridge programme. My crew is a geologist leading two horticulturists, a wildlife biologist, an entomologist, a biochemist, and a political scientist. We're all overqualified, but in the interview the qualifications were less important than saying why you care about public land and how you'd want to better it. Especially with urban greenspace, it's so interdisciplinary that any kind of scientific background has some important role. Parks feels like doing communism every day so it's an amazing workplace full of passionate environmentalists who make those spaces their babies.