Really raised beds (Wasilla: organic, cabin, garden)

[MissingAll4Seasons]

As I look out across the lake that is supposed to be a yard, I'm pondering how to build my garden for next year. I'm already planning on having raised beds since the soil crap here, if you can even find more than a scratching of it with all the muskeg. So, given how squishy it seems to be in the spring/early summer (it is BONE dry in the late summer BTW), I was wondering if it might just be better to build my garden beds on platforms so they are at counter height rather than messing around with the ground for anything except the taller vining plants.

Would having elevated boxes make the soil way too cold since the air can get underneath them, or will it actually help the soil in the box warm up faster since the heat's not leaching into the frozen soil? If I built up a stone/log platform and filled it with gravel and then put the soil box (6-12") on top of that, would it help with the temperatures? I'm just trying to avoid having my spring crops flooded out and still be able to get a little bit of an early start without going the extreme and expense of a full-on greenhouse right now (have to build the cabin first!). I could probably dig out swales for drainage to help a little, but I kinda like the idea of tending the garden at a comfortable height (my knees aren't what they use to be). I also figure having it up high might keep the bleedin' hares and mice out... since they ate the one tote/container garden I tried to start earlier.

Anyone have any experience gardening in outdoor raised platforms? Any suggestions?

[tigre79]

Usually raised beds help the soil warm up (ambient heat can warm it from the sides as well as just the top), and you can speed it up even more by putting black plastic (like trash bags) on top.

[MissingAll4Seasons]

yeah, I know how raised beds work, and that putting *clear* plastic on them helps them warm up even faster... but I'm wondering if having them completely up off the ground so that they are exposed to the air on the bottom will make the soil colder or warmer. I mean when the air temp is still well below freezing at night.

[Minnesota Spring]

Is it possible to put some kind of insulation underneath the raised beds, so the heat does not escape into the frozen soil below, but remain in a top layer of good soil?

[akck]

I'd suggest placing foam board insulation at the bottom to protect it from frozen ground and place a wind barrier on the sides to protect it from cold wind. Foam on the sides would protect it from a cold wind, but would also insulate it from heat too. If you're planning on building it elevated above ground, I'd foam board the open sides to keep a dead air space under it. BTW, I've never done anything like it, so I'm just thinking about what might work.

[MissingAll4Seasons]

I think that foamboard on the bottom (with a couple holes for drainage) would work to keep the cold wind off the bottom, especially if I built the platform on top of stone or wood walls with some gravel and dead air inside. I'd definitely insulate the whole box during the cold weather and put a cold frame of some sort on top. I don't think I'd be able to grow anything during the winter, but if I could keep the snow and wet out it *should* start warming the soil up in there faster once the sun comes back out in the spring.

Since I have to have ground beds for the tall & vining stuff, I guess I'll just buid two identical boxes with identical insulation and cold frames, one elevated and one on the ground, and then stick soil thermometers in both to see what happens. There's no harm in starting with a small garden the first year to see what works. Patience just isn't one of my strong suits and I'm used to having a larger garden... lack of fresh veg is starting to get to me

[Jerseykat]

MissingAll4 I'm not sure on raising up the raised beds, but here are some links to AK gardening
which you probably know but hey I'm a googler:

interesting seed company with articles
MAIN (http://www.denaliseed.com/main.html - broken link)
raised bed article from UAF
https://www.uaf.edu/ces/publications-db/catalog/anr/HGA-00132.pdf (broken link)
fairbanks gardening
http://www.ptialaska.net/~pbabcock/patch/
garlic in an Alaska raised bed
Raised beds and garlic in the North - Far North Gardening Forum - GardenWeb
blog about Alaska gardening (lol they follow your blog!)
Wasilla Alaska Garden Adventures: What We Have Learned... (http://chateau-listeur.blogspot.com/p/normal-0-false-false-false-en-us-x-none.html - broken link)

[MissingAll4Seasons]

Yep, I've checked out most of those sites and all the UAF pubs... I think the folks at UAF are afraid of me and my funky questions now LOL I was talking to them the other day about keeping worm compost bins in the barn under the rabbit hutches (with kitchen scraps also) during the winters and then putting the worms from the bins back out into the garden beds and compost heap every spring... they just looked at me like I was a little bonkers hahahaha.

[jinak]

Hello Missing,
I relate to your planting difficulties! Your ideas are intriguing and Since no one can really tell you whether or not getting the beds off the ground will really help, I suggest you try a test section before putting all your efforts(and cash) into building all your gardens this way. You might even try it yet this year with some things that will grow quickly, lettuces or herbs. I liked the idea also of using the foamboard, but personally would wonder about any toxic ingredients from the board getting into my soil and plants over time(I like organic approaches best). But I don't know if they would leach anything worrisome anyway. Still, I'd check it out.
I know a woman who uses something called a lasagne method which utilizes layers of newspaper, but am not really sure how she does this, but she always had good results. Anyone else hear of something like this and how it works?
Best of luck to you. I also hope to overcome some gardening challenges in Alaska, but am getting the "older knees" also! LOL!

[MissingAll4Seasons]

Jinak - I've read about the lasagna method and one of my friends down south (GA) uses it and is very successful. I'm not sure how well it would work up here since things decompose so slowly in the cooler temps, but it might be worth a try in one bed for a season.

Once the foamboard is made and off-gases from the extrusion/expansion process it's inert (as long as it's not exposed to UV), so I'm not too worried about it leaching anything weird into the soil... it's certainly safer than most pressure treated lumber. But I do wonder if having the insulation permanently on the bottom might make the soil too hot in the summer during our long sunlight... probably great for tomatoes and melons, but not so much for all the cool temp plants that grow great up here all season long (you won't get lettuce and broccoli in the summer in TX for sure!)

I'll probably end up building 4 identical boxes, with bottoms so they're portable, and then put 2 on a platform and 2 on the ground, one insulated and one not, just to see if there's any difference. If it turns out that one does better than any of the others, then I can just move the others and set them up again. Most of the beds only have to have about 6" of soil in them for the fast crops like lettuce and radishes, only a few need 12" like carrots and turnips. I'm going to try an expansion unit for the potatoes... start them in 6" of soil, put a shallow box frame around them and keep adding up soil and more frames as the grow up... that way you don't have to make a really deep bed and mess with trenches and hilling, just add another frame and soil just where the plant is.

Old knees and aching backs are such a drag, but imagine how great your garden would be if everything was at a comfortable working height, easy to reach and easy to see... it'd be a dream come true