Shaded Treebox Ideas

[Anonymous]

We have a shaded tree box in front our DC rowhouse that is in terrible condition. The total box (including my neighbor's portions is 8' wide (road to sidewalk) and 28' long (including a very large tree at one end). The soil is filled with rocks (which I suspect a long past owner dumped as decoration), weeds, and very hard soil. I'd like to make the space more attractive, but not sure what to do. I want something that can handle low light, is low maintenance, will allow reasonable access to people who parallel park on the street, and doesn't terribly mind being a pet bathroom. I am concerned that getting anything to grow there will require significant fixes to the current soil (removing the rocky infill and replacing with new good soil), but maybe I am underestimating the resilience of plants. Here are a few things I'm considering:

(1) Trying to get grass to grow in the tree box, but I think too difficult to accomplish and too maintenance heavy. We have decorative grasses in our yard, but nothing that requires regular mowing, and I don't think I would keep up with it.
(2) Pick a few nice plants to grow along the center of the tree box (small evergreen flowering shrubs in the center with hostas around them?), and cover the rest in mulch to keep the weeds at bay. I figure I would just need to dig a reasonable sized hole for each plant, but not need to address most of the bad soil in the box. Does that sound right?
(3) Try to get ground cover that doesn't mind the terrible soil to take root and expand through the area.

Has anyone dealt with a similar space? Any reactions or ideas?

[Anonymous]

That’s a tough situation! Lack of water and dog pee are probably the biggest challenges. Hostas need quite a bit of water to stay looking good. How about huchera instead of hosta? They like shade and don’t mind less water. There are some tough grasses that might work, like little bluestem and purple lovegrass. Plus maybe some ground covers like violets, packera aurea, and creeping phlox. Then see what thrives and plant more of that the following year.

I think you can probably leave most of the rocks, maybe making them into piles where you dig them out for planting holes. Then mulch pretty heavily - the mulch will help build soil and will keep in moisture while the plants establish.

[Anonymous]

Thanks this is very helpful! Any recommendations for evergreen shrubs that might do well in the space? Something that would add some modest height over a hosta/huchera.

[Anonymous]

Itea Little Henry (sweetspire) and dwarf varieties of Pieris japonica are compact shrubs that will grow in partial shade. If you have deer your hosta will get decimated.

[Anonymous]

Are you familiar with DC's regulations about treebox planting? I'm guessing no, since you mention evergreen shrubs as an option (not allowed; nor are the rocks the prior owner put down).

Bascially, there are restictions about where in the treebox you can plant, and what you can plant, and lots of things you can't do.

The toughest part is that no plant can grow taller than 18 inches, but you also can't use plants that spread by runners, so no ground covers.

Take a look at:

DCMR 24-109
and
DC Public Realm Design Manual (v. 2.1, March 2019) [https://planning.dc.gov/sites/default/files/dc/sites/op/publication/attachments/DDOT Public Realm Design Manual.pdf ]

[Anonymous]

Anonymous wrote:That’s a tough situation! Lack of water and dog pee are probably the biggest challenges. Hostas need quite a bit of water to stay looking good. How about huchera instead of hosta? They like shade and don’t mind less water. There are some tough grasses that might work, like little bluestem and purple lovegrass. Plus maybe some ground covers like violets, packera aurea, and creeping phlox. Then see what thrives and plant more of that the following year.

I think you can probably leave most of the rocks, maybe making them into piles where you dig them out for planting holes. Then mulch pretty heavily - the mulch will help build soil and will keep in moisture while the plants establish.

Based on the regs, yes to huchera, dwarf varieties of little blue stem like "Chameleon", purple lovegrass, violets. No to packera and creaping phlox because they spread by runners.

Technically, the rocks have to go.

[Anonymous]

Anonymous wrote:Itea Little Henry (sweetspire) and dwarf varieties of Pieris japonica are compact shrubs that will grow in partial shade. If you have deer your hosta will get decimated.

Both of those shrubs are too tall. 18 inches max. Also you can't plant anything with deep root systems.

[Anonymous]

Try:

Tiarella cordifolia (foam flower)
Heuchera (coral bells)
short varieties of cranesbill
fringed wild pertunia
native columbine
Indian pinks "Little Redhead"

grasses for shade:
poverty oat grass
white tinge sedge
Wood's sedge
Hobbs blue bunny
Pennsylvania sedge "straw hat"

[Anonymous]

Dwarf varities of ecchinacea are complaint and are said to stand up to dog urine.

[Anonymous]

Anonymous wrote:Are you familiar with DC's regulations about treebox planting? I'm guessing no, since you mention evergreen shrubs as an option (not allowed; nor are the rocks the prior owner put down).

Bascially, there are restictions about where in the treebox you can plant, and what you can plant, and lots of things you can't do.

The toughest part is that no plant can grow taller than 18 inches, but you also can't use plants that spread by runners, so no ground covers.

Take a look at:

DCMR 24-109
and
DC Public Realm Design Manual (v. 2.1, March 2019) [https://planning.dc.gov/sites/default/files/dc/sites/op/publication/attachments/DDOT Public Realm Design Manual.pdf ]

I took a look at the regulations, and I also took a look at the state of enforcement on my block and throughout DC (non-existent). I am mindful of not blocking car and pedestrian access, but a couple small shrubs will not do that. If DC tells me to remove them, so be it.

[Anonymous]

Anonymous wrote:Try:

Tiarella cordifolia (foam flower)
Heuchera (coral bells)
short varieties of cranesbill
fringed wild pertunia
native columbine
Indian pinks "Little Redhead"

grasses for shade:
poverty oat grass
white tinge sedge
Wood's sedge
Hobbs blue bunny
Pennsylvania sedge "straw hat"

Thank you for the suggestions! I'll investigate.

[Anonymous]

Anonymous wrote:Dwarf varities of ecchinacea are complaint and are said to stand up to dog urine.

I was hoping to select something that would remain attractive in winter, but maybe I need to give up on that goal.

[Anonymous]

Anonymous wrote:

Anonymous wrote:Dwarf varities of ecchinacea are complaint and are said to stand up to dog urine.

I was hoping to select something that would remain attractive in winter, but maybe I need to give up on that goal.

I suppose defining attractive is key. If you look at designers like Piet Oudulf, Adrien Bloom, and the like, they focus on structures of plants that provide winter interest. For example, the seed heads of ecchinacea are a winter attraction (and food for birds). The red branches of red twig dogwood are a winter interest. The golden tan wave of grasses in winter are pretty. Unless a plant has a winter color, you are relying on interesting form and movement to keep the space attractive until spring.

Piedmond Master Gardens have a nice article about winter interest. https://www.piedmontmastergardeners.org/article/reflections-on-the-winter-landscape/

[Anonymous]

Thanks again for all the input. Here is my modest initial effort.



https://ibb.co/PZQjsYVg

[Anonymous]

If it's 8 feet wide, I'd say it's more of a tree lawn than a tree box, and that should leave plenty of space for people to get out of their cars.

For winter interest, you could consider a dwarf Camilla.