22 July 2011

Raised Veggie Beds, the Good, the Bad and the Ugly

I've been growing veggies in raised beds now for about 7 years, choosing the method for three reasons. One, we live in an urban area and I just thought it easier to bring in uncontaminated, fertile soil rather than till down. Two, I like the modern confinement and lines of raised beds and always heard they could be really productive in a tight space. Three (and this is actually the biggest reason), for most of that time we had a blind black lab that knew no boundaries. That last reason was also cause for us to build the beds more than 14 inches high. Good bumpers for a dog of Libby's size.

Unfortunately, those beds - which were installed in August 2008 to replace an older rotting set that came with the house - are already buckling and breaking apart. They are only 3 years old!

For sure I should've used cedar instead of untreated pine (it was cheaper and I knew it was a risk). For sure, our construction is not ideal (I recommend using some metal braces on the corners instead of screwing the sides into a post). And for sure, I would never use wood to build raised beds again nor probably recommend it, especially in our climate. Wood doesn't last, meaning it's really less sustainable in the long run, and the soil dries out extraordinarily fast, particularly because these beds are too tall.

In a hot, dry climate like Central Texas, raised wood beds just don't seem to be the best way to go. Now, that being said, I've seen some that are extremely successful for some reason or another. Those are much lower to the ground and bracketed, which are big pluses. And maybe someone is replacing the wood every year or using treated wood filled with chemicals. At any rate, I've pretty much sworn them off.

The bloggers over at Root Simple, based in L.A., have also been questioning the wisdom of raised beds, and I really like their list of trade-offs:
Raised beds have some pluses and minuses. Lately I've been thinking about their drawbacks. Namely:
  • Cost
  • How fast they dry out in a hot climate.
Now I can also think of a few reasons one might want to grow vegetables in a raised bed:
  • You do a soil test (and you should do a soil test, especially if you live in an urban area) and the results come back showing that you have heavy metals in your soil.
  • You live in a very wet climate.
  • A disability prevents you from kneeling or leaning over to garden.
  • Your soil has no contaminants, but has some other problem, say bad texture or lots of buried rocks/chunks of concrete.
  • You have dogs/rabbits/chupacabras, etc. 
I've come to the conclusion that for Southern California and, by extension, any dry climate, raised beds are a bad idea unless, of course, you have any of the issues mentioned above.
For more on the topic, check out "Are Raised Beds a Good Idea?"

My plan when these fall apart for good, which unfortunately I believe to be sooner than later, is to keep the raised bed idea, but use native limestone for the walls and sink the beds much lower. If I have pets that needs some boundaries, I'll install a little waddle fence or something around them. I think the stone will prevent drying, and of course, will last a lifetime.

But it'll also mean a lot of heavy lifting and, I'm saying "hell to the no" on that chore this summer for sure!


Anonymous said...

I don't pretend to be an authority on raised beds, but mine were made with salvaged cinder block with fake tumbled stone tops from Lowe's. I painted the sides of the cinder blocks to make them look like stone, and the effect isn't that bad.

Also, while I didn't do this myself, in "Mrs. Greenthumbs Plows Ahead" by Cassandra Danz pgs 122-123, she recommends creating sunken beds with stone sides to protect plants from the drying wind and to better catch rain water for desert gardens. I realize we don't live in the desert, but damn, we're getting pretty close! Sounded interesting.

Good luck, Laura

Bob said...

I've gardened in raised beds for well over 20 years now and agree with you on the drying out in the hot weather. You would be right to go with masonry of some sort. It certainly does help keep the moisture in. A lot of mulch helps but it's not enough if the beds are in full sun.

Good luck on your upcoming back breaking job. I'll be watching.

Anonymous said...

In this context, the word you want is "wattle," a woven lattice of wood strips or some such materials.