Table Top Design

Here is a drawing of a table top garden that I'm building.  This one is 10' long 4' wide and stands 40" from the ground to the top of the sides.



My TT design incorporates end notches and tabs to join the boards.  I will use landscape spikes that are 9" long and 3/8" in diameter inserted into holes pre-drilled in the center of the 2-by dimension through the notches and tabs.  Legs are 2 pieces of 2x4 glued together so that the inner piece has the side resting atop it.  Legs will be attached through the sides with carriage bolts.  Not shown in the picture are braces shown at each corner that screw to a side and an end that are used to square the sides with the ends.  The intent is to make a knock-down assembly to give the most flexibility for moving beds or whatever might arise.

Beds will be lined with 1/2" hardware cloth with landscape fabric next to the soil.  You can see that I plan to use a lattice to support the weight, bracing the hardware cloth about every 10".  The hardware cloth will be attached using fender washers and screws along the perimeter placed in the approximate center of the span between lattice strips.  I will probably attach some cross braces to the legs just to add strength and stability.  The resulting box should give me about 7" of MM depth.

Because I'm in Texas, I expect very hot summers and relatively mild winters.  Wind is also an issue because it wicks moisture out of everything when it blows.  I plan to mulch the top of the beds, but I'm concerned about the bottoms.  It occurred to me that I might put some 1" thick foam insulation panels on the underside.  This should protect against most of the wind wicking and might even help hold heat in roots during the winter.  I intend to make the long bed pictured into a hoop house just to see what, if anything, I can grow during the winter.

I offer this for comments, suggestions, criticism or whatever you can use it for.

   Cheers 

Looking good.    Remember, with your tabletops so high in the air, you may need to make adjustments for hoop height and trellis height.  I found a 16' cattle/feedlot panel across a 4' aisle works well for a trellis between 2 tabletops giving me enough room for growing and still low enough for harvesting.  Would also make a good base for a hoop house over the 4' beds.  I have to take care with how I stake into the ground because all my beds are over my septic drain field.

How we make do with designs.

My beds were from a kit and had hinge like corner brackets with a foot or so long pin/stake through it for staking the bed to the ground and holding the corners of the boards together.  But I put my beds up on cinder blocks as tabletops.  The stakes, of course, poked up above the 7" boards.  So I used these built in stakes and put the 1/2" PVC pipe on them hooped over my beds. Cover with Net in the summer and plastic in the winter.

I also have though about adding foam to the bottom of my tabletops to help with the drying winds and heat.  I find my tabletops need more water than the buckets on the ground.  I have also thought about wrapping/tacking plastic around the base of my tabletops to the ground for the same reason. 

 Hmmm maybe that will be this years project.  With ten 4x4 beds ( 2 dedicated to strawberries which I hope will fruit this year) and a dozen or more buckets,  I don't need to add more beds.  


Kay

rabbithutch wrote:  It occurred to me that I might put some 1" thick foam insulation panels on the underside.  This should protect against most of the wind wicking and might even help hold heat in roots during the winter.

I offer this for comments, suggestions, criticism or whatever you can use it for.

   Cheers 

Don't forget to poke some holes in the foam for drainage! Keep us posted as this seems very interesting.  

Wardinwake felt he was getting too much evaporation on the bottom side of his TTs, so he re-did them with plywood bottoms.  It seems to me like 6 mil plastic over the weedcloth would have accomplished the same thing.

I'm in a cooler climate, and the MM temp is usually 5-8° cooler than the ground temp, which slows growth a week or two.  I've been retro-fitting some boxes with foam board to see if it will warm things up a bit.

For efficient supplemental heat in winter, soil heating cables are sweet!

https://squarefoot.forumotion.com/t6953-heated-hoop-houses

boffer wrote:Wardinwake felt he was getting too much evaporation on the bottom side of his TTs, so he re-did them with plywood bottoms.  It seems to me like 6 mil plastic over the weedcloth would have accomplished the same thing.

I'm in a cooler climate, and the MM temp is usually 5-8° cooler than the ground temp, which slows growth a week or two.  I've been retro-fitting some boxes with foam board to see if it will warm things up a bit.

For efficient supplemental heat in winter, soil heating cables are sweet!

https://squarefoot.forumotion.com/t6953-heated-hoop-houses

In the peak of summer, our soil temps rise to the high 80s while our air temps are north of 100 - and it is dry with dry winds sometimes reaching speeds too high for sailboating.  I think that soil temp in TTs might be even higher than ground soil temps.  The flip side is that most winters - tho this one was exceptional - are relatively mild without too many hard freezes.  I think that insulating the bottom of the beds and covering the tops might let me grow cold season veg and perennial herbs without having to put a soil heater under the soil.

Yes, I plan to have holes for water drainage.

Thank you, all, for the input.