Wicking Bed Experiment
So I used our neighbor’s old kiddie pool to try a proof of concept this summer. A Wicking bed is simply an enclosed reservoir of water over which you put a growing medium and grow stuff. It is supposed to be low water use and the research I found was intriguing enough to want to try it!
So, figuring the easiest and cheapest way to try this was with the old pool, I raked up some of the horrible gravel in our backyard and put 3 inches worth of it into the bottom after I put down landscape fabric to minimize scratching and damage to the pool. I’ve read that ideally you would have 12 inches of water reservoir and another 12 of media, but the pool isn’t that deep, so 3 inches is it. The nice thing about this pool is that it's essentially double walled so it provides a little insulation around the edges from the heat.
I filled the pool with water so it would be easier to level the gravel and determine where the drainage hole should be drilled on the side. The hole is positioned at the top of the gravel.
The theory is that even if it rained or I overfilled the reservoir, the excess water could be drained away and not flood the bed as the water could seep out. Once I was satisfied with the levels, I put down landscape fabric over the gravel and loaded the top with potting soil suitable to container gardening. This was May 15th, then I was too busy to do any more with it and didn’t plant anything in it for over a week, but that gave it enough time to fully soak up the water and hydrate the soil.
So I visited Baker Nursery and got some small potted plants and planted them in the pool garden and in less than one month it looks like this...
I have filled the reservoir with water twice since I put this together, that's a little more than every other week! I've been amazed with the results and am keeping an interested eye on this project as the temperatures heat up and see how long between waterings it can go through the summer.
--------------- UPDATE July 25th 2012 ------------------------------------
Well, I can't say enough great things about this experiment. I'm very happy with the results! I've been watering on average every 5 days, so a little more than once a week in the worst of summer. The plants have exploded in growth all over the place. Here's a recent photo as of this morning:
You can see part of the chicken coop and run in the background. The wire fencing around the bed has effectively kept out the dogs and I haven't had a chicken try to jump in now that there is wall to wall greens in the bed. Apparently the visibly open dirt was the siren's call for Easter Chicken to hop the fence.
Everything has grown well and this morning I picked a watermelon out of the garden. I've been picking a few tomatoes and peppers from the bed and of course sweet potato greens. The tomato needed to be tied upright after going a little too long between waterings and when everything wilted a bit there were too many fruits on it for it to perk back up to straight without some help (that's the string). You can see the hose as it is filling up the reservoir, I usually just let it run for about 10 minutes while doing other chores outside. All in all, I'm going to do this again, bigger, deeper and probably more than just one!!
SIDE NOTE: I do have a question for all you out there. I picked my watermelon after observing that the little curled tendril opposite was fully dry and crispy and the melon gave a wonderfully promising sound when thunked. I had tied it up in burlap to keep it out of the dog's reach since it grew outside the fence. Because of this was no soil spot to check for color change. When I cut it up this morning it was pink, not red, and the black seeds were not yet black, but light brown and only changing to black in spots. It still tastes good, but I can imagine how out of this world it would have been if I waited. So what are your secrets for melon picking?