A person whose hobby or job is growing flowers in a garden is called a gardener. If you want homegrown flowers and veggies, get to know a gardener.
If you grow vegetables professionally, you're called a farmer, but if you design, tend, or care for a flower garden, you're a gardener. Planting anything on a small scale, in your own backyard, also makes you a gardener. The word gardener was a common last name starting in the 13th century, from the Old French jardineor, and the Old North French gardin, "kitchen garden or orchard."