For many Washingtonians, the holidays aren’t complete without a trip to the Botanic Garden Conservatory to see the Capitol made out of dried plants.

An annual tradition since 2004, the conservatory’s holiday display celebrates the season with replicas of national monuments and a toy train display, all made from natural materials. The original exhibit was limited to a replica of the Conservatory and a railway display, but Kentucky designer and landscape artist Paul Busse and his firm Applied Imagination have been adding to the collection ever since.

This year, nine miniature monuments are on display in the Garden Court, laid out according to their geographic location around D.C. The garden railway is next door in East Gallery.

“It’s become a tradition in Washington,” said Holly Shimizu, executive director of the Botanic Garden. “People would be hugely disappointed if we didn’t do this for them.”

To construct the miniature landmarks, Busse studied architectural drawings and photographs of each historic building. He used acrylic foam boards to create the basic structure and then added dried plant material to craft unique architectural details.

On the miniature Jefferson Memorial, for example, Busse used a dried-out gourd to re-create its dome. On the Capitol, Busse used small willow branches to create the columns and beechnuts to make the base of the Statue of Freedom.

Other replicas include the U.S. Supreme Court, the Thomas Jefferson Building of the Library of Congress, the Botanic Garden Conservatory, the Smithsonian Institution Castle, the Washington Monument, the White House, the Lincoln Memorial and Capitol Hill row houses.

Next door to the miniature monuments, toy trains weave in and out of a display that includes mountains, castles, bridges and fairy tale characters all made of plant matter. Called “Windows to Wonderland,” this year’s exhibit allows visitors to follow seven trains through a magical wonderland with six hamlets: Fairy Tale Trails, Santa’s Village, Secret Mountain, Castle Mountain, Caterpillar Garden and Gremlin Corner.

“People always say to me, ‘The trains are coming back, right? When are the trains coming back?’” Shimizu said. “The truth is grown-ups and people of all ages love it as much as kids do.”

And now, visitors can take a cell phone-guided tour of the gardens. By calling 202-730-9303, they can take a tour completely at their own pace and decide which rooms to visit.

Each room tour lasts a few minutes and delves into the history and background of plants and the themes of the exhibits. But be warned: The tour doesn’t point out specific plants.

In addition to the exhibits, the Botanic Garden will host two holiday wreath workshops 10:30 a.m.-12:30 p.m. and 1:30-3:30 p.m. Saturday. Participants should register in advance and the cost is $40.

The conservatory will also stay open late for holiday music concerts throughout December. The building will be open 5-8 p.m. Tuesday for harps and singing, 6-8 p.m. Thursday for klezmer music, 6:30-8 p.m. Dec. 16 for a cappella, 5-8 p.m. Dec. 18 for male a cappella, 6-8 p.m. Dec. 23 for jazz and 6:30-8 p.m. Dec. 30 for holiday music.

The “Windows to Wonderland” exhibit will run through Jan. 4 at the Botanic Garden, located on the Capitol grounds. The conservatory is open daily from 10 a.m. to 5 p.m., including all weekends and holidays, and admission is free.

Andrea Cohen contributed to this report.