Dear Miss Floribunda,

I remember a column you wrote some time ago in which you objected to piling mulch around the base of trees and didn’t seem entirely enthusiastic about wood chip mulch in general because of the nitrogen it takes out of the soil before it decomposes. I’ve continued to use mulch for weed control, adding fertilizer with it, but my beef is that by the end of summer it doesn’t seem particularly effective. I wonder if you or one of the many advisers you claim as relatives could suggest alternatives to it — aside from constant weeding in the hot sun, of course. I’d be truly grateful.
Mulch Obliged on Madison Street

Dear Mulch Obliged,

As it happens, the Hyattsville Horticultural Society has invited Thomas Rainer, a noted landscape architect and  expert on mulch alternatives, to be keynote speaker at the upcoming Hyattsville Green Expo on Saturday, September 17. Mr. Rainer has designed landscapes for the New York Botanical Garden, the U.S. Capitol grounds and the Martin Luther King Memorial and writes a highly regarded blog called Grounded Design. He is the co-author with Claudia West, another stellar landscaper, of the award-winning Planting in the Post-Wild World: Designing Plant Communities for Resilient Landscapes. One of the many innovative ideas in their book, for example, is to use such natural underplantings as ferns and other shade-tolerant plants to keep down weeds and retain moisture under your trees and shrubs. In addition, you will learn how to plan, harmonize, and time-share your plantings in a way that not only cuts down on your own work and is ecologically beneficial but pleasing to the eye. Too often our amateur attempts to use native plants can result in awkward-looking and seemingly unkempt gardens. Our guest will tell you how to use native plants, often mixing them with non-natives, in an esthetic way. The expo itself starts at 10 a.m. and runs to 4 p.m. Mr. Rainer gives his talk at 1 p.m., right after the cake-cutting ceremony to celebrate the centennial of the Hyattsville Horticultural Society (HHS).

Yes, the HHS is 100 years old this year despite a severe period of decline. It was begun in 1916 by three professors from the University of Maryland but had dwindled to one member in her 80s by 2006. Inspired by what this lady told us, the members of the Hyattsville Preservation Society, who had been pushing for a gardens committee, decided to try to revitalize the venerable old society instead. It was no longer limited to professors and professional horticulturists but was opened up to amateurs and new gardeners. It has grown like a weed and now counts 140 gardeners on its membership list. A table will be staffed by HHS members to answer your gardening questions and help you sign up as a new member, should you wish. Even if you don’t, you get a free piece of birthday cake and I’ll be there to serve it to you. You will recognize me by my hat.

You also won’t want to miss the rain barrel promotion, sponsored by the Hyattsville Environmental Committee, the Prince George’s County Department of the Environment, and the Plumbers & Gasfitters of Local 5 Washington D.C. . You will learn how to order a suitable rain barrel, how to apply for a rebate, and where to pick it up and have it installed without cost. Also, Community Forklift will have a table with interesting information, as will the Master Gardeners of Prince George’s County, the Chesapeake Conservation Landscape Council, the Anacostia Watershed Society, and the Prince George’s County Department of the Environment. Doody Calls, a pet waste removal service, will be represented, as well as Stihl Inc., a rechargeable lawn equipment company that offers tools promoting efficiency without pollution. The Department of Natural Resources (DNR)will provide information on tree pruning and how to promote an urban tree canopy. A food truck will offer refreshments and water.

The next meeting of the Hyattsville Horticultural Society will include a plant exchange at the home of Joe Buriel and Dave Roeder on Saturday, October 15. The meeting takes place at 3909 Longfellow Street and runs from 10 a.m. to noon.