Wednesday, October 7, 2009

What lizards know about thermal mass...

Here's a happy report of one small success with the concrete beds. It's now early October with near freezing nighttime temperatures and the concrete beds are performing like a champ already. They warm perceptibly during daytime hours and then re-radiate at night, keeping the soil in the beds noticeably warmer than that on the ground. The slight (15 degrees) tilt to the south seems to be about right...runoff isn't a problem and the sun nowadays is right where the beds can grab big chunks of it.

The plants inside (all cool weather crops) seem more than enthusiastic about being there too. I'm enjoying bumper crops of spinach and chard at the moment and snow peas are probably about one week from ready. Kale and other brassicas are coming on strong too. Carrots look healthy. There's even a rogue tomato and a sunflower in there for good measure.

One challenge I've had with raised beds is that of keeping them watered. However, the cool season goal for this one means that it gets plenty of rain. I do have to baby it a little more during sunny season, but find so far that it's not overwhelming or excessively thirsty.

Will post new pictures soon of this fall bounty!

Wednesday, February 18, 2009

Paved paradise?

One of the non-building structures in the garden is a set of raised beds to be placed along the fence on the north end of the lot. Raised beds have been a part of the plan since the very beginning, primarily because the lot drains so poorly thereby preventing early spring gardening.

However, I still had to decide how to make the raised beds. Apart from being elevated, the other thing I wanted from these beds was enclosure, both to keep out pernicious grass and to enable 3 or even 4 season gardening. Here in Oregon it's entirely possible to grow some things year round using a simple cold-frame or greenhouse setup.

To facilitate the extended season gardening, I determined to tilt the raised beds up at an angle of about 15 degrees toward the south so as to take advantage of the winter light. That's a very old practice actually.

So, we're raised and tilted. Here comes the hard part: concrete.

I deliberated long and (um) hard about materials to make the beds. I've used wood in the past, but it either has to be treated (not very nice!) or will rot. At 46, I tend toward longer lasting things and less back work, so the prospect of replacing wooden beds every few years is not much to my liking.

So, I started to consider concrete and eventually opted for it despite the fact that I have reservations about adding more concrete either to my small paradise or to the larger wonderful planet we're so lucky to live on.

In my case, however, it was actually the permanence of concrete as a building material that swayed me. One of my goals in doing the garden was to create a long-lasting set aside for growing things. In my neighborhood, there's currently a lot of pressure to increase housing density, often by adding smaller houses in the back portions of larger lots. The site for my garden is in fact a corner lot: prime real-estate for plopping in a duplex rentable to nearby college students.

That's exactly what I don't want to happen to that lot.

So, several cubic yards of reinforced concrete my way of locking in the garden aspect of the lot...hopefully in perpetuity. I recognize that it's sort of a blunt approach. Ultimately my ability to make it a beautiful and enjoyable space may prove the most effective deterrent to urban encroachment. Nonetheless, I'm sure the concrete will slow them down a bit. And, there are side benefits such as its thermal mass (good for heat loving plants), durability (see above regarding my back), inertness (better than treated wood), etc.

And, I promise that as I set about paving paradise, I'll do my best to make it handsome.