Gardening where the sidewalk ends

Parking Strip Gardening in Portland? October 5, 2008

A friendly commenter pointed out here that there may not be as much parking strip gardening going on in Portland (the proverbial “City of Roses”) as I seem to have found in Seattle. I’d love to do a fact-finding field trip to P-town about this subject, but in the meantime I was curious to see if there are different rules, as well as perhaps different attitudes, about utilizing this space.

In Seattle the parking strip is owned by the property owner, and the City expects it to be maintained according to certain guidelines. Of course, there is not a huge amount of enforcement, and I’ve never heard of anyone’s garden being condemned or ordered to be altered for any violation. Most people leave it alone but a growing number are using the space in a more creative fashion.

It interested me to read, on the City of Portland site, that in their city the parking strip is considered “part of the public right of way” but the adjacent property owner is responsible for maintaining it. Perhaps any hesitation by Portlanders to get into digging in this part of the dirt is partly attributable to this, and also to the fact that planting, pruning, or removing a tree out there requires a (free) permit from the city. The site doesn’t give much information about what kinds of plantings are permitted or encouraged – they mostly seem concerned about keeping tree limbs from blocking visibility and signs (hence the site’s depressing picture of a rainy day street scene with an offending tree branch keeping a school crossing sign from view).

Here is a blog post about starting a drought-tolerant parking strip garden – maybe this is just the tip of the iceberg. This one near Reed College sounds like a beauty, too bad they only put in one tiny picture. At least there are lots of plant names and great advice on soil amendments for making it drought tolerant. I think that one’s going to have to go on my field trip list. And one of my fav blogs, Nest Maker, has a funny post about goings on in the parking strip.

Wondering what your city’s regulations are about getting going on a parking strip garden? Check out its municipal web site, sometimes listed under the Department of Transportation, and if you have an Urban Forester or City Arborist, that’s another good place to start.

'Brandy' rose


Dr. Seuss Trees September 18, 2008

The City of Seattle has a program where neighbors can band together and request a set of free trees for planting in the parking strip, from a list provided by the city. It’s a great way to green up the block and increase the density of the urban forest.

A street several blocks from my house had obviously done this, but perhaps they either didn’t get the city’s help with pruning the trees or they did it themselves with poor results, because they ended up looking like this:

Crazy tree

The trees are so tall and spindly, with the branches so oddly spaced and shaped, that they provide no shade and are just, well, kind of weird-looking. Seattle is home to a great organization, Plant Amnesty, which tries to raise community awareness about proper pruning, recommends certifited arborists, and otherwise educates tree stewards about proper care methods for keeping trees healthy and well-shaped. A quick visit to their site is worth it if only to see their “Bad Pruning Gallery,” truly a chamber of horrors.

I can see why this one was on the city’s list – its twirlybird seeds are really something, turning pinkish now.


Going from the city’s list of approved small trees to a few online searches, I’m going to guess that this is acer grinnata, or Amur maple. If that’s the case, it should have some pretty amazing red foliage later in the fall. It’s too bad the trees weren’t treated better when they were young – their natural shape is more shrub-like, but with proper early pruning they can grow upright without looking quite so much like they belong in an illustration from “Green Eggs and Ham.”


Soil Testing August 14, 2008

That email from the city kind of freaked the heck out of me. I never thought to have my soil tested for contaminants. The soil test kits sold through seed catalogs and garden stores only work for pH and macronutrients, not contaminants. To really find out what’s in your soil, you need to send it to a lab. I think since my kid eats what I grow, I’m probably going to do it.

The Washington State University Ag extension program has a number of links to soil testing resources here. They are largely for the Pacific Northwest, but for other regions you could just look online for “soil testing” and your area, or contact the closest ag program.

Here‘s a link to the WSU list of soil testing labs for the Pacific Northwest. It’s pretty hefty, a 13 page PDF.

I obviously need to do more research here! I will try to post results soon.


Nitty Gritty II

I asked the Seattle City Arborist to comment on my original post on city regulations, and apparently I got a few things wrong! Mea culpa. The city does NOT in fact own the parking strip (or planting strip, as they call it), the homeowner does, with an easement for use by the city. There are a number of regulations about height and materials, quoted below, along with the arborist’s contact info in case you have further questions.

"Thanks for your interest in planting strip gardening and sharing
information with the general public. I am attaching a Client
Assistance Memo (CAM) that discusses planting strip regulations.
A list of CAM's published by SDOT is located on the web. Scroll
down to"Urban Forestry" for a list of documents published through
our division, including planting strips.

It sounds like you found the list of suggested plants on the web
(the link is found under the "What's Happening" section). The list
is currently being updated. 

Although the list may not be exhaustive, and gardeners are encouraged
to be creative, they do need to follow some parameters. Plants grown
within the area equal to or less than 30 feet from an intersection
may not exceed 24" (2-feet) in height at maturity. This is so that
visibility is adequately maintained. (cars and pedestrians visible
to each other). When a planting strip is 5-feet wide, or less, plants
may not exceed 36" (3-feet) in height at maturity. This is to help
assure pedestrian safety/visibility as well as to maintain pedestrian
walkways and the roadway clear of overgrowth which may impede travel
on the right-of-way. With wider strips, it is possible to put in scattered,
taller plants, if planted in the middle of the strip. 

There are also regulations about "hardscape" - which may include
planting beds in the strip. Raised beds may be constructed from
timber but rocks or bricks that are easily moved (read here "picked
up and thrown") are not allowed. Permits are required for raised beds.
Permits are also required to plant, prune or remove trees.

Concerning food gardening, while there are no regulations prohibiting
it, SDOT does not recommend growing food in planting strips because
of safety concerns. The concerns include the proximity of gardening
activity to roadways/traffic and unanswered questions regarding soils
and contaminants. I would, at a minimum, recommend a comprehensive
soil test before considering food gardening in planting strips. 

One more thing, I work with the traffic circle stewards and just
recently initiated a LIST SERV as a means of communication for that
group of gardeners. I've included information about signing up."

Linden L. Mead, Certified Arborist
Seattle Department of Transportation
Urban Forestry
P.O. Box 34996
Seattle, WA 98124-4996

Hoo boy, can o' worms. Does anyone get a soil test before putting
in food plants on the street? I sure didn't think to! Maybe I need
to get the next post up soon, on raised beds and soil improvement!

The Nitty Gritty from the City August 13, 2008

OK, say you have a barren parking strip that you want to transform. What do you need to know from your city (town, county, burg) before you get started?

In Seattle, the parking strip is owned by the property owner with an easement for use from the city. The following information applies to the city of Seattle – please contact your local municipality if you live elsewhere.

Before you dig, know what’s under the ground. The last thing you want to do is hit a water main! The City of Seattle will come out and mark power, water, and sewer lines for you if you call 1-800-424-5555 to request this service.

Do you want to plant a tree? There are a few restrictions, but check with the city arborist for a free permit and some advice. Neighbors can also band together and request free trees from the city of Seattle, although choices are somewhat limited.

The city has a list of recommended plants for parking strips (they call it a planting strip) here, but you are certainly not limited to these. Let your imagination run wild and use the street as your canvas!

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