raising beds off the ground

So we moved to our rental in October and the rains really started a few months ago. Long story short our property backs to a fairly used road and the house itself sits say 15 feet below street level with a 10 foot area making a steep slope ending at hip level with a retaining wall and then our yard. I had planned on growing some stuff in topsoil plus compost on the hillside and then a 2x4 and 4x4 Mel's mix box but the yard has horrific drainage and is very swampy by the retaining wall, but that isn't even the issue. I planned on rototilling the lawn (after it dries) so I tried digging some temporary trenches in attempt to make the water level lower and speed up the evaporation process. Besides that not looking like it will actually work my streams appear to have fairly significant urban run off (aka rainbows of gasoline run off that appear after the first rain) in them where the water has pooled. I have 5 young children, 2 with developmental delays who certainly don't need to add lead poisoning or whatever else is in gas ickies to the mix, so now I am hesitent to be planting right in the ground How expensive would it be to put a plywood bottom on them (and I was considering getting another bed or a billion, I discovered SEEDS so want to grow 854753437 different things now despite currently only having 24 spaces) and then putting the beds on something like bricks to raise them just high enough that they aren't sitting in gas laced soil? Is that a good plan? Do I even need to worry about it? This site sees to imply I'd probably be ok as long as I didn't grow leaf or root crops http://www.extension.umn.edu/distribution/horticulture/DG2543.html Thoughts?

MHoB,
If it were me, I'd keep my soil as far away from the shiny, hydrocarbonic rainbow reflections as possible.

For different reasons, I am building all of my beds to be raised. I actually have them about 2 feet off the ground to encourage our plentiful rabbit and gopher population to find food from another source.

Each box (3 x 3) was considerably less than $20, with the bottom. Actually cost less than one of the sawhorses I mount them on.

Hope that helps.

-NA-

There are many good reasons, just like yours, for getting gardening boxes off the ground. We call them 'table tops'. If you search with that term, you will find lots of ideas. Here is one thread to get you started.
https://squarefoot.forumotion.com/t41-table-tops-take-sfg-to-a-higher-level

Any opinion on if a combo of cinder block and the using hardware cloth would work without having a solid layer of cinders under the bed? Do I make sense? Like using cinder blocks on the 4 corners (on a 4x4) to raise the bed 8 inches off the ground, maybe with a block in the middle as well) and then hardware cloth and then building a bed over it? If building larger I'd do cinder space cinder and some center cinders but not solid cinders. I don't really want true table tops (3 ft off the ground) so my kids can still tend to the garden and we can plant the toms and melons I had planned, but I need something to get the boxes a solid 6 inches or more off the ground. Or would it just collapse you think? Would I have to screw the hardware cloth into the cinder? Is that possible (I mean without buying 76464 tools to do so ) I can't recall how rigid h.c is.

Also we just disassembled my kids bunk bed because it seemed to be slowly coming apart due to swaying. Wondering if I might be able to do something and make a "bed" from the bed frame of the bottom bed that was seperating.... wheels turning...

You're on the right track. I would fasten the HC to the box with screws with washers, or nails bent over, or wire fence staples. I definitely would provide some sort of support in the middle, one block at the very least.

I think I can visualize a single bed being used as a short table to hold a SFG box. Is that what you mean?

so wire fence staples could be pounded into the cinder blocks then? Of course if I could get free or nearly free cinders I wouldn't need to be so stingy.

DId I misunderstand? I thought you were making a wood box frame, with a HC bottom, to sit on top of cinder blocks.

No, staples won't fasten to cinder blocks. My husband says there are ways to fasten to blocks, but for this situation, advises against it.

Well I do have a 2x4 and 4x4 box, made of wood but they are 5 yo and starting to really show their age (rot) plus I was thinking of making more boxes this year so was thinking about what materials I could use for those as lumber is pretty $. Just trying to think of all my options

https://squarefoot.forumotion.com/t5716-experiment-to-deal-with-pure-sand-and-high-water-bills#49172

Take a look at the beds at my son's house. We raised them for a different reason, but they are boxes with hardware cloth bottom, two 1x4 supports under the bottom and lined with weedcloth. Hardware cloth is attached with U nails.

Kay

Hardware cloth makes a great bottom for raised beds, if you don't want to use plywood. However, you MUST put the hardware cloth over supports. Putting a cinderblock underneath just the hardware cloth will not be sufficient. Boffer shows some great examples in the following post.

Building Table Tops

Here is a picture of the three supports I placed on the bottom of my TT. Then the hardware cloth was attached over the supports. This is the same concept if your are just raising your beds off the ground using cinder blocks.
Using 2X2's for the supports, you do not need to add a cinderblock under the middle of your bed.

gah that looks way complicated and/or $$

You should read this thread on building boxes and using cindar blocks for legs.

https://squarefoot.forumotion.com/t5250p15-i-m-making-progress-and-gardens

myhouseofBOYS wrote:gah that looks way complicated and/or $$

The supports are 2X2's held by joist hangers (less than $1.00 apiece)
I will admit, I got carried away with the way I attached my hardware cloth. Just learning how to use some POWER tools.

furballsmom you are probably right I am just super overwhelmed. I went from planting seedlings last week thinking I'd be ready to plant to it raining so much we couldn't get the compost to me discovering I need to redo my whole set up in addition having no medium to put them in. And I have seedlings that are going to want to go in the ground soon. Plus I ordered a bunch of seeds. I have well over $60 invested in stuff and um no where to put it.

myhouseofBoys

I can understand where you are at right now.

I started some of my seedlings as early as Feb 16. Even though our frost date is well past, we can't put heat loving plants out until May. Our highs in the summer are mid 60's to mid 70's so we don't get a lot of heat and so have problems growing tomatoes, peppers and eggplant. Melons are impossible unless you have at least a hoop house.

I am in the process of converting from the old SFG method of amended soil to straight Mel's Mix and from on the ground raised beds to Table Tops. There is a lot involved in these changes. Rain does not help one little bit.

At least you found out that you did not want your gardens directly on the ground before you filled the boxes with Mel's Mix and planted. That would have been a deal breaker for me.

An easy bottom is a sheet of plywood installed with deck screws, which is what you mentioned in your opening post. Just make sure you drill 1/4 inch holes in the center of each Sq Ft, then an extra hole in each corner. Cover with weedcloth, so you don't lose your precious Mel's Mix. I have no idea how much plywood costs but it certainly is an easier solution and might be less expensive than supports, brackets, hardware cloth as well as weed cloth.

The reason I don't use plywood here on the OR Coast is because we have so much rain (We had about 14 inches of rain in March) you really need marine plywood, which is really expensive and has more chemicals in it. Plus, once you cut Marine Plywood the cut end will still absorb water because it is no longer sealed.

Sit back, relax a bit and decide what will work best for you and your family.

myhouseofBOYS wrote:So we moved to our rental in October and the rains really started a few months ago. Long story short our property backs to a fairly used road and the house itself sits say 15 feet below street level with a 10 foot area making a steep slope ending at hip level with a retaining wall and then our yard. I had planned on growing some stuff in topsoil plus compost on the hillside and then a 2x4 and 4x4 Mel's mix box but the yard has horrific drainage and is very swampy by the retaining wall, but that isn't even the issue. I planned on rototilling the lawn (after it dries) so I tried digging some temporary trenches in attempt to make the water level lower and speed up the evaporation process. Besides that not looking like it will actually work my streams appear to have fairly significant urban run off (aka rainbows of gasoline run off that appear after the first rain) in them where the water has pooled. I have 5 young children, 2 with developmental delays who certainly don't need to add lead poisoning or whatever else is in gas ickies to the mix, so now I am hesitant to be planting right in the ground How expensive would it be to put a plywood bottom on them (and I was considering getting another bed or a billion, I discovered SEEDS so want to grow 854753437 different things now despite currently only having 24 spaces) and then putting the beds on something like bricks to raise them just high enough that they aren't sitting in gas laced soil? Is that a good plan? Do I even need to worry about it? This site sees to imply I'd probably be ok as long as I didn't grow leaf or root crops http://www.extension.umn.edu/distribution/horticulture/DG2543.html Thoughts?

Howdy MHB:

Mary and I currently have 24 Square Foot Garden boxes. Except for those that we plant climbing tomatoes, cucumber, squash, peas etc. all are at table top height. Some of the TT are on purpose built 2X4 frames, some sit on cable spools and one on an old kitchen cabinet base. They vary in size from 2'X4' to 4'X8'. They also have a variety of bottoms. Some are hardware cloth and some solid with plywood or other sheet wood bottoms. Very little of the material used to build the boxes themselves or the supports under them were purchased. We visit construction sites, behind big box stores, trash collection days and ask folks if they or anyone else has excess lumber. Sometimes the sizes are not exactly to the foot, but, the plants don't seem to care as long as they have Mel's Mix and a grid they are happy. Cinder block, brick or almost anything that will support the weight of the box will work just fine. Don't overstress about your boxes. Look around and find what is free and ask, ask, ask. It may just surprise you what you can get that is free. I like free.

God Bless, Ward and Mary.

so I see next to Cost Plus next to the dumpsters but not in them we have pallets. We picked up one as that was all that would fit in our van but I figure we can get one at a time until we get however many we need. It is 40x47 1/4 and my "4x4" box is 49 1/4 the "2x4" smaller at the "2" length of course. I am thinking there has to be some simple way to make them work right?