Planter Project - Part 1

I decided to make some planters that go along the parapet walls of our green roof, so we have more growing space.

Keiter and I rented a zipcar SUV and went out and bought 125 6-foot Forestry Stewardship Council Certified redwood fence pickets.  We had a little adventure getting them, because the only way they would all fit in the car was if we put the passenger seat all the way forward, the driver's seat as far forward as we could, and if Cindy (who is considerably shorter than I) drove home.  I had to ride home laying on the stacks of lumber in the back.  It's a good thing they were pretty wet.  Had they been dry, my entire front side would have been full of redwood splinters!

Anyway, we survived, got things stacked in the basement, and had the zipcar returned on time.  Here's a shot of the stack after I'd built one or two planters... Yup, I own a perfectly serviceable mitre saw, but I'm using a hand saw.  It's good exercise and practice.

The following Sunday, the experiment began!  My plan was to make planters that were three boards tall, sleeved over the capstones, and functioned as self-irrigating or wicking planters.  I wanted to get one long side and one short end out of each fence picket (using 6 fence pickets per planter).  I started  by working on finding the right dimensions for the planter.  I made a rectangle the same width as the capstones, carried it up to the roof, and took a look.

I like the look of it, but I wanted it to sleeve down father over the capstones.  I'm planning to use a pond liner for the bottoms of these (to make them lighter, and to save wood), and I wanted the bottom edges of the sides of the planter to sit relatively close to the capstones, so the pond liner didn't pooch out the sides once the water got in there.

 I ended up making the planter wide enough to sit on the outsides of the flanges.  I cut the contour of the capstones into the end boards to make the planter sit low enough.  Before pulling them up to the roof, I staple the pond liner to the sides.

Then I fit these corner pieces in - they hang down below the edges of the capstones, and I'll be able to attach brackets to the bottoms of the corner posts that wrap around the underside of the capstones if the planters aren't stable enough on their own.

Here's one after the pond liner is installed and trimmed, and I'm starting to stretch the filter fabric.

This is what it looks like after the filter fabric is stretched, stapled, and cut around the corner pieces.  I've created a water reservoir in the bottom section of the planter.  The dirt will sit on top of the fabric.  How will the water get up into the dirt?  You'll see in a minute.

In the basement, I pre-assemble the wooden rectangles of the planter (you can see the 2nd and 3rd courses in the background in the photo above).  So, once the fabric has been trimmed, I sleeve the wooden rectangles over the corner posts and screw the whole thing together, like so: 

This is how the water is going to get up into the soil:  I set three little net cups in position on the fabric in the bottom of the planter.  The soil is going to wick water from the lower trough up into the upper chamber through those net cups.  You can learn more about this style of planter by doing an internet search for "Self Irrigating Planter" or "Wicking Garden."  

I install the net cups in the fabric by cutting a little "X" through the fabric and pressing the cup in.

Finished.  Don't ask me how I'm going to get water into the bottom reservoirs; I haven't finished deciding about that yet.

By the way, it sure is easy to tell which side of this picture is our roof and which is our neighbor's!  I can tell you from personal experience, black roofs (or is it "rooves"?) are HOT - and not in a good way!

I set the first planter on the wall between my house and my neighbor to the East to see what it looked like.  On this side, I plan to install trellises on the backs of the planters to act as a bit of living screen.  I already like how much of my neighbor's unfinished roof is obscured by the body of the planter box.

A wider perspective:

The next day, I made 3 more.

And then I made 4 more.  I spent both of my days off this week making planters.  4 planters/day is the speed at which my process has settled.

In case it wasn't clear earlier, I make the bottom rectangle (with semi-attached pond liner) and the 2nd and 3rd rectangles in the basement.  Then I hoist them up to the roof on ropes.  Ignore the messy back yard.

So, after another weekend spent making planters (today and yesterday), I've got a grand total of 12.  I really hope they work.

I had originally planned to have the planters in groups, with some empty space in between.  But now that we have so many of them up there, we have really started to like the way they define the space and give us a bit more privacy.  We have decided to make enough planters to fill both walls on both sides.  I've already ordered more pond liner.  I guess I know what I'm doing next weekend too!

So, I have to make more planters, figure out whether I need to level the planters to make the water in the reservoirs submerge all 3 net cups equally (since they follow the slope of the roof), decide whether I want to buy and install float valves in each planter (which is probably going to be too expensive, since I can't go with valves that can be fouled by roots growing into them), or if I just want to plumb tubing into the planters from the drip irrigation system and fill them according to a timer rather than their water levels.

And I've got to buy a ton of potting soil and carry it all up to the roof.

Nevermind thinking about that, though!  Here's Keiter - showing off her chicken wings!