Fellow Hill residents, I have a question for you. Why are your tree boxes such a mess?
I ask with sympathy and understanding. When I bought my home on the Hill, I inherited an overgrown, unsightly tree box, and after a year living in my home the city agreed with me and sent me a warning that said if I didn’t shape up my shrubs I’d get slapped with a $75 fine.
Of course I spent more than the cost of the fine to clean up the space, and four years later the public space, which is my responsibility, is rather presentable, less the city detritus that finds its way into the warm embrace of the grasses and mulch that make up my tree box.
Whether you call them postage stamps, hell strips or tree boxes, which is what the District officially calls the space between the roadway and the sidewalk, the space is often more difficult to cultivate than the American plains during the dust bowl, what with things like people, pets and trash all conspiring against us, but that doesn’t mean we shouldn’t try. A few tree box tolerant plants mixed with some creative edging and mulch can make all the difference, and maybe even add a little something to our property values.
Tree Boxes: There is a reason why they are called tree boxes
While most properties have a tree box, not all tree boxes have a tree. If you’d like the DDOT’s Urban Forestry Administration to plant a tree in your tree box, you can fill out a request for a tree online; however, the deadline to request a tree be planted in the 2010-2011 planting season has passed, but it may not be too late. Requests submitted after June 15 are not guaranteed a tree, but may be considered.
If your tree box is already home to a tree, Margaret Missiaen of the Capitol Hill Garden Club recommends that homeowners keep their tree boxes free from weeds, soak the soil with 20 gallons of water once a week and cover the area with a thin layer of mulch. Missiaen warns that “plantings in the tree boxes can rob the tree of moisture, especially around young trees that do not yet have much of a root system.”
And the current warm weather isn’t good for newly planted trees, which need a thorough soaking once a week during dry spells. Missiaen recommends putting a garden hose at the base of the tree and letting it run at a trickle for 30 to 40 minutes.
Missiaen does not believe in plantings around new or mature trees. “If you must plant flowers in the tree box,” says Missiaen, “wait until fall and plant small bulbs, such as crocus, grape hyacinth or small daffodils.” The Garden Club gives away bulbs for planting in public spaces.
Tree Boxes: When only plants will do
If your tree box is tree free and you don’t wish to, nor do you think you qualify for a tree—there are rules in terms of the number of plantings on a block and how close new trees would be to other established trees—there are plantings that are easy to care for and add value to the space.
If you’d like something that is green and easy to maintain, Matthew Roberts of Ginkgo Gardens suggests homeowners start with “the ubiquitous liriope or lilyturf that you see in most of the tree boxes around town. It’s there because it’ll grow in the sun or the shade, damp or dry soil.” A few common varieties are ‘Big Blue,’ which has green leaves with purple flowers, as well as Liriope spicata and Liriope muscari.
“One of my favorites,” says Roberts, “is ‘Silver Dragon,’ which has white stripes.” Roberts also recommends the variety ‘Variegata,’ which has yellow-green stripes and pairs beautifully with Roberts’ secret tree box weapon: Lysimachia nummularia or creeping jenny. “This is the same color as the stripe and its flat, spongy, round leaves contrast the sword shape of the liriope.”
If your tree box sees less sun and more shade, Roberts suggests ajuga ‘Black Scallop’ or one of the many varieties of tiarella, “a lovely mounding perennial with floating creamy flowers from which it gets its common name, foamflower.”
Roberts also suggests homeowners turn their tree box into an “urban herb garden.”
“The lyrical quartet of parsley, sage, rosemary and thyme will all work well in a sunny location,” says Roberts. For a different and even more” carefree mix” Roberts suggests substituting mint, chives, lavender, oregano, sorrel and even eucalyptus.
And when the only moisture we see is high-humidity, look to “two hardy workhorses that pair up perfectly: St. John’s Wort and Barren Strawberry,” says Roberts. ”These both have great drought resistance once established and the small yellow blossoms of the barren strawberry will be mirrored by the larger canary blooms of the St. John’s wort.”
Finishing Touches
Whether your tree box is home to a tree or a few tree box tolerant plants, simply adding some creative edging and mulch can make all the difference, and maybe even add a little something to our property values.






