ATLANTIC BOTANICAL GARDEN: atlantabotanicalgarden.org or 404-876-5859. Docents lead tours each Tuesday afternoon (free with admission). Private group tours can be arranged.

BLOEDEL RESERVE: Bainbridge Island, Wash., bloedelreserve.org or 206-842-7631. Reservations required to visit the reserve. Free group tours for six or more; call well in advance.

BROOKLYN BOTANIC GARDEN: Brooklyn, N.Y.; bbg.org or 718-623-7200. Guided tours (free with admission) offered weekends, 1 p.m.; no reservations needed. Group tour offerings (718-623-7220, for 20 people or more) include garden seasonal highlights with buffet lunch, $32 a person; Palm House luncheon tour, $53-$63; "Meet the Curator" tour, $40 (with lunch $60); art and garden tour, $45.

CHICAGO BOTANIC GARDEN: Glencoe, Ill.; chicagobotanic.org/tours or 847-835-5440. Earth Day Walk in search of wildflowers, April 28; Heritage and Lakeside Gardens tours, May 5; tree care tours, May 12 and 19. Spring Garden Walks, Saturdays, 1 p.m., April 28-May 26, free. Ticketed tours, $4-$32, include tram tours (starting in April), walking tours, group tours, behind-the-scenes tours of greenhouses and laboratories, a "Bright Encounters Tour" by tram (Heritage, Rose and English Walled Gardens), twilight tours on summer evenings. Boxed lunch option on some tours.

DENVER BOTANIC GARDENS: botanicgardens.org or 720-865-3533. Drop-in tours, 11 a.m. and 1 p.m., Saturdays and Sundays; themes include general highlights, water gardens, trees and other subjects.

DESERT BOTANICAL GARDEN: Phoenix, Ariz.; dbg.org or 480-941-1225. Daily public tours, "Taste of the Desert" tours, nighttime "Summer Flashlight" tours (free with admission). Beginning March 1, birdwatching and spring wildflower tours.

GARDEN IN THE WOODS: Framingham, Mass., newfs.org or 508-877-7630. Open April 14-Oct. 31. New England Wild Flower Society offers tours ($10 per person) of seasonal highlights, cart tours for visitors needing mobility assistance.