You may want to try using the same stuff I just applied to my bridge to help it last longer outside:
http://www.minwax.com/wood-products/exterior-clear-protective-finishes/minwax-helmsman-spar-urethane
I will find out this summer if it helps any as the bridge over my pond sits in direct sun light all day, last year it pretty much turned the bridge black… we will see what happens!
Spar varnish is called that because it is designed to protect the spars of a sailing ship, those sticks that hold up the sails. It is the ultimate in UV protection. To get the best results, use four coats.
I bought a 4 x 4 x 2 ft box from “Lifetime” a company that sells play ground equipment and other outdoor stuff. It is made of plastic. I filled it with good soil and grew some killer tomatoes in it last year. It is going again this year and is looking good. I can’t remember to water all the time, so I hooked it up to my timed irrigation, and all is good.
We saw plastic container gardens at Lowes when we bought the soil. Nice, but a little pricey for me right now - just got cut back more 8 hours at the morning job.
The wood I’m using has already been outside for over 4 years, so protecting it at this point would make little sense. Marilyn may paint the outside just so it doesn’t look so tacky!
Drew up the cut plan tonight and discovered that the base will only be 8" above grade to get to my target height of 33 inches. I may not bother with posts and use some leftover landscape blocks to get the elevation.
The cut plan…
Got a lot done on Saturday. The design changed a little. I decided to put the legs inside the frame. This added a bit more work but gave me really solid corners on the box.
Here are some progress pics. The frame takes shape…
Deck and Sides are cut…
(http://lsc.cvsry.com/post4/ContainerGarden-02.JPG)
Legs cut and attached to frame…
(http://lsc.cvsry.com/post4/ContainerGarden-03.JPG)
Deck trimmed for corner posts and attached…
(http://lsc.cvsry.com/post4/ContainerGarden-04.JPG)
Side walls attached and lined with 3mm PVC board…
There are still a few more details to take care of before dirt is loaded, but the heavy work is done!
Nice project Jon,
You or your wife will really enjoy the raised bed for the plants but they are a little awkward with
taller plants like tomatoes or pole beans.
Your description of the bottom treatment that you intend may be more expense and trouble than it is worth, that’s just based on my experience though, your mileage may vary. The soil has a tendency to leach through the weed block cloth and, over time, will fill the spaces between your slats creating a solid bottom anyway. I just drilled a series of 1/2 inch holes in the bottom boards and placed 2 layers of weed block on the bottom and one layer up the sides. My sides were made from 6 inch boards so had spaces between.
Be aware that you are on the edge of a very slippery slope. That one box will work really great but you will find that it just isn’t large enough, so maybe one more for a few extra plants next year.
Then maybe a little larger one so you can grow sprawling plants like melons or squash. Do you wonder how I know about this:), It is how it happened to us.
Now it’s like this.
Later
Rick
Very nice gardens Rick. And thanks for the advice. I haven’t built that part yet - so I guess I’ll just skip that extra work. My reasoning was to keep the soil away from direct contact with the wood and allow a little air circulation. As you point out, that will be defeated over time.
Drain holes were always in the plan. I have a large sheet of corrugated plastic I could line the bottom with, but I think that water would tend to wick between it and the wood - so probably won’t bother with that either.
Rick, that looks fantastic. Invite him to your place, Jon! Tell him he can bring his tools…
Maybe you want to get some of those “Topsey Turvy” tomato planters and model an Australian railroad
Definitely don’t want the wife to see Rick’s gardens - she might get ideas!
I finished the inside last evening and placed it in it’s new home. Read the instructions on the bags of Miracle Grow Garden Soil only to find that the 15 bags of soil we bought, is not soil at all, but a soil enhancer that needs to be mixed with soil. Don’t you love labeling. Now I need to buy soil - not even sure where to do that if what is labeled soil isn’t.
Those concrete block raised beds look great, but…be aware that frost can knock the hell out of them…
I know of a few people that have tried to keep frost from pushing out on the walls by lining the inside of the walls with 4 inches of foam…which absorbs the expansion of the soil…
I wish you all good fortune in your endeavors.
…while you guys are busy trying to grow your tomatoes…I’m off to the farmers’ market buying them and saving all that work…but I am missing the pleasure of growing my own…I agree…!!
Fred,
This is California, we don’t do things like frost heave. Some of those have been in place almost ten years.
Somebody has to grow them so you can go to the Farmers Market for them 
Jon,
Try a landscaping place they should have loam by the yard or fraction of.
Rick
Thanks Rick -
Been reading up on my Miracle Grow Garden “soil” purchase. Most reviews are horrible. Stuff is basically ground up construction debris with added fertilizer! Glad I didn’t rip open the bags before discovering this. They are going back to Home Depot for a refund.
There are several landscape supply places around and I have access to a trailer so that will probably be the route we take. Mix in our own peat and fertilizers and perhaps a bit of perlite.
Good choice Jon,
Around here we can get a loam/compost mixture for just a couple dollars more than the straight loam
it is usually way cheaper than adding a bunch of bagged amendments.
Very imformative there Boomer!
Looks very sucessfull!
We use old stock tanks. Bash a few holes in the bottoms with a splitting maul. We had these laying around, but you can get them new for less than the cost of building wooden ones. Or find them out in the country. Most ranchers have ones that leak laying around. The fill is three way mix (top soil, sandy loam and manure) and a yard of compost I hauled in from a local materials yard.
Hey Boomer great post.
Under varmints you forgot to mention the ringleader of the little devils, the common gopher.
He is the reason all my concrete block “bunkers” have concrete bottoms in them 
Thanks Boomer. So what your saying is my 3 days of labor should be tossed out because I used plywood and PT posts :] In my defense; the plywood has been mellowing outdoors for 5 years, and the PT posts for 15 years. I’m pretty sure they have both gassed out by now. I may coat the posts with vinyl just to reduce the contact area, and the plywood is already lined with PVC - so I hope I’m OK.
[following comment is not aimed at Boomer]
John - the stock tanks look like they work great. Be careful of the Organics folks - they’ll be telling you that your veggies are contaminated with Zinc from the galvanizing :]
Going to try and pick up some kind of planting medium this weekend. Bagged stuff is too pricey. I can get a yard of topsoil for $24 - going to try the local nurseries and landscape supplies for something better.
This weekend we picked up a half yard of topsoil, a bale of Sphagnum Moss and a bag of organic soil enhancer. Cost $20 more than my 15 bags of Miracle Crap and I had enough to fill the container, replace the dirt in all the flower pots and repair a wash-out on the lawn.
Today I added plastic edge cap to cover the exposed plywood edge. Mostly this is to keep from scraping arms, but will also help protect the wood.
Marilyn planted some carrots and radishes by seed. We’ll add tomatoes after Mothers day.
I’d take some more pictures but we are in for 40 days and nights of rain.
