2012-09-13

With a rubble wall

I had popular songs from the 80s running through my head the other day, one of which I thought apropos of my wall building activities. You mean it's "rebel yell" not "rubble wall"? Ah well, I always preferred his earlier efforts.

I've had a much slower start than I wanted on gardening projects at the new house. I've been there 13 months and I got stymied pretty much at month 2 in an incident that I may go into later.  There's been some benefit to this, however. Since I've been living with the garden in an unremediated state I've had ample opportunity to prioritize and let the best ideas percolate to the top of my brain while dropping the overly ambitious, too costly, unfocused, or otherwise flawed ideas. Here's the first significant garden project that has percolated to the top through its urgency due to the coming winter rains and its conceptual simplicity - being less grandiose and more practical than, for example, replacing my front lawn.

There is a drainage problem in my side yard where several fruit trees are planted. This is a south-facing yard, but with the fence and neighbor's house providing shade, it's not unbearably bright and there seems to be ample reflected light for vegetables as well as the usual native plant suspects. However, the existing fruit trees aren't doing as well as one might hope, in part due to the fact that they are planted a slope between the neighbor's house and mine and you can't irrigate them, particularly with the existing shrub sprayers, without instantly getting abundant run off.

Here's what it looked like when I first moved in.  My house is at left and we're looking through the front gate to the back gate. There's three types of citrus (one of which produced last year - yummy mandarins, but none produced this year), peach (no eatable production, though raccoons or possums got a few), apricot (no production, ever), and pomegranate (the best producer and very tasty too).
Note the dry-stacked bricks actually set onto on the pathway. Don't do this.  The previous owner must have put them there in a vain attempt to retain water and soil soil that runs down the hill.  Copious agapanthus is a landscaping hallmark of the previous owner, somewhat reduced today and destined for great reduction.

Compounding the water issues are that the neighbor's paved side yard can only drain to my property, a small pitch of my roof drains to this same side yard onto the concrete walkway (visible at the far end of the path in the above photo), and that same paved walkway has been raised by roots which makes water pond against the side of my house. None of these are good, but the solution is straightforward: terrace the hill area and install a retaining wall to decrease the slope and allow water to percolate in. Widen the walk area to include space for soil drainage, break out and re-set the concrete to slope it away from my house, and direct roof drainage onto pervious surfaces where it will seep in.  Simple, right?

I needed to get started by removing the ineffective irrigation lines placed along the bottom of the slope where I will soon install a wooden retaining wall.  I was always in fear of breaking off the sprayers with a casual misstep as I worked in the yard or even walked in the dark down the path.  Plus, spraying up the hill with these old style shrub sprinklers was always such a pain and the run off was so copious that I never did it for fear of the waste. There's inexpensive shrub sprinkler retrofits available now that use much less water and apply it much more evenly.   I decided the irrigation could go at the top of the hill and I'd irrigate downward, salvaging and reusing the old irrigation with upgraded sprinkler heads -  I tried a Toro Matched Precipitation Rate (MPR) sprinkler head, which seems like one of the smarter new designs.  MP Rotator seems to be the Cadillac of new designs.  Oh, along the way I discovered not one but two defunct galvanized irrigation lines that I felt I needed to rip out.  Since they ran the length of the side yard, there's a lot of galvanized to recycle.

I pulled out the PVC line, made some minor repairs, rerouted the incoming water line, and buried it in a shallow grave^H^H^H^H^Htrench near the top of the slope. I don't know if this was a bad choice or not, but I decided that for ease of future repair or replacement the shallow trench could be covered by the rock rubble that I would use for the narrow top tier of my terrace.  I find rock aplenty on this property whenever I dig. Below, the shallow trench and rock rubble poised to make my retaining wall.



Natives can go out of harm's way and mostly out of the irrigation on the narrow upper tier.  With a rubble wall like this I was going for a look that was rustic and of this place, since this type of rock (Catalina Schist) is commonly found in my area and is widely used as building materials.

There's not much to it, when its all installed (below).



Next step: Build a redwood retaining wall at the bottom of the slope and figure out something to do with the bricks (there's not enough to build a retaining wall).  As a last resort, they are easy to give away on Craigslist.

2 comments:

  1. do you have your redwood yet???

    ReplyDelete
  2. Nope. Need to schedule that.

    ReplyDelete