A master gardener carefully plucks buds from a plant. She threads the remaining delicate flower stems through plastic rings. Growing this plant is like walking on a tight rope between two towers. One wrong move and the perfect Thousand Bloom Mum is toast.

You can usually see mums (chrysanthemums) in people’s backyards in the fall. But you probably won’t see one like this unless you go to Longwood Gardens’ fall Chrysanthemum Festival in Kennett Square, Pennsylvania. It takes 18 months and thousands of hours of work to grow the mum. In the week before the event, at least six people work full time—on just this plant! When the festival starts, the amazing mum stops visitors in their tracks.

But here’s the trouble. Almost no one knows how to grow the famous mum. Once, young people studied with master gardeners to learn the secrets of horticulture (gardening). But now fewer people choose careers in horticulture. It usually doesn’t pay a lot of money. Master gardeners worry. They will not be around forever. What if someday no one remembers the secrets of growing a plant like the Thousand Bloom Mum?

How would you keep the secrets from being lost? The gardeners at Longwood are using videos. This year, three college students are documenting how to grow the mum. They follow gardeners as they do the difficult work. When they finish, the nine videos will be used to teach future generations. They hope the videos will send a message to young people: Horticulture is cool. You can do it too!

This year, gardeners at Longwood want their chrysanthemum to outdo itself. Instead of 1,000 blooms, they want it to have 1,500. If it gets much bigger than that, it won’t fit through the greenhouse door!