Wild Boy

Cristo Balete wrote:You can line the bottom with large concrete pavers, or pour concrete about 3" thick on the bottom.   I think bricks might wiggle out of place, but if you've got a cheap supply, since those in the gravel as much as possible.

I've started doing dry-pour concrete for most of my pads.  This would take a few days in your situation, (it can take a month if it's a car or tailer pad, since concrete needs to cure, regardless of how it got there.)  But you just need it to solidify.  I think the beds are deep enough that the alkalinity won't matter, it will be outweighed by the organic mix of the soil/compost/mulch.  

Pour out the powder from the bag, keep it about 3 inches thick, level it with the back of a rake, then with a fuzzy paint roller and that gets it pretty even.  Then, this is important, just mist (not sprinkle) the top layer with water from a hose or a  mist sprayer until it's shiny.  This creates a crust.  slowly you will add water until it permeates the 3" thickness of powder.   Then wait 20 minutes, mist it again.  Every 20 minutes mist it until it's shiny for 5 or 6 times.  Cover it, keep the sun off it, let it sit overnight, then sprinkle it with water from the hose at least 3 more times 20 minutes apart.  If you can touch it with your finger and it doesn't give, let the water run gently all across the top until it's shiny.    Repeat throughout the day several times, keep it covered.  When it feels really solid in a few days after repeated soakings, then it's probably safe to add the soil.

I've done dry-pour for a car parking spot.  I spent a month after spreading 4" of powder, putting wire mesh in the center of the powder, wetting it down a couple times a day, keeping it covered, made sure it was solid, starting to cure, and could support the weight of a vehicle.  That was two years ago, and there's not a crack in it, it looks great.

the nice thing about dry pour is if you get interrupted it's no problem.  It's not as heavy as wet concrete.  You can walk on it gently if you need to, but it should be resmoothed if you do.  I did a wide pad under an arbor in my garden and couldn't reach the backside of it, since it was next to a fence, but walking on it was fine.

Check it out on YouTube.  

Interesting, I will look at the videos the tube!

James MacKenzie wrote:all the above comments are valid - tbh - just fill them as is!

you could run some 1-2 inch branches along the seams at the bottom on the inside to help with dirt seeping out - a little soil around the outside perimeter should work too.

those are dandy beds - they are also tall!! you could probably do fine taking the top half off each on and double your beds (if you have more room) - 18" is deep enough for almost anything.. it will help with buckling  as well (less height kicking out)..

the rocks on the bottom are fine - yes some soil will get in there but eventually fuse in... side seams should be fine.!

Thanks, I will put the wood around the edges.
best of luck!

Amy Gardener wrote:Nice beds!
Speaking from a "learned-it-the-hard-way" experience, now I secure 1/4" hardware cloth along the bottom of all open raised bed frames. Unlike an impervious liner, hardware cloth provides good drainage for plants and soil to prevent water logging and rotting. The mesh prevents tree roots from running over and slurping up the water and nutrients in the generously nurtured beds. The mesh also prevents unwanted critters from burrowing up from under the beds to dine on the luscious roots.
Luckily, your beds are still empty which makes the job a lot easier. Digging out the soil to line the bed bottoms after the beds were filled was not a happy experience for me.

Thank you, I will check out the hardware cloth!

Timothy Norton wrote:Welcome to Permies!

I actually would recommend not going the caulking route, I think after you fill them and it initially settles you won't have much soil leakage. To be safe near the bottom, I would recommend the route of getting some branches/scrap wood and filling the bottom layer with that as a sort of hügelkultur/space filling approach. The small seam from stacking should not be an issue from my experience.

Something that might prove to be an issue is once you fill up those beds, the pressure on the walls can cause some bulging/twisting. If you have the ability, you might want to beef up the cross ties to just be safe.

[youtube]https://www.youtube.com/watch?
v=zqnqSBBXvM0[/youtube]

Thanks for the video and the information!

Nathanael Szobody wrote:Wow,  fancy! I like the green color. Ditto to the above replies. They look real deep,  so I'm curious,  what are you going to fill them with?

I was going to do some logs, mulch, and dirt.

Tereza Okava wrote:hm. that is a lot of stone to consider moving out of the way. I think you'll find that eventually some roots may end up going through, hard as it may to believe. I don't think you're going to be losing soil into the stones (it's like garden pots, it looks like it's all going to go out those little holes at the bottom, but once the roots get going and mycelium and soil biota, that dirt isn't going anywhere).
You may find old canvas or even carpet to throw under them if it concerns you. Those would both be really good and safe options (obvs depending on what kind of carpet it is). But I wouldn't worry too much-- personally i'd just plant right in there on top of the rocks with nothing in between, but that's just me.

Thanks, I am going to level the gardens as well.

Tereza Okava wrote:Welcome to permies! those are some nice beds you have there.
I would say don't worry too much about the seams and leakage, frankly. You're going to have all sorts of organic matter in there holding your gorgeous dirt together.

About the stone-- is there something underneath you don't want the roots getting to? Or is it just a matter of not wanting to get the stone out of there?
You could conceivably use cardboard or even fabric (depending on your drought/drainage situation, the fabric might differ). both will eventually break down. Roots will eventually penetrate the stones. Once you fill up with dirt it will hold the fabric in place.

Thanks for replying and the compliment! There is about 6" to 8" of stone under the gardens and was looking for something to stop the dirt and roots from going into the stone.

Hi, I am looking for a solution for my raised bed gardens. I double stacked them and I also will have them on stone. I am looking for something that is nontoxic to seal the seams between the beds and something to put on the bottom to keep the soil from draining out. I am looking for something that will last. Is there a nontoxic caulking for the seams? I was looking at NSF rated pond liner but it is expensive. The beds are 3'x6'. Thanks!