Anyone used vertical potato grow box/potato towers?

Dark

Hey brain trust

Has anyone had much experience with grow towers? I'm currently looking at building a concept one to test how effective they are for gardens with tight spaces.

Pic for example 

the idea here is to grow potatoes vertically to save space in the garden. In order to do this multiple box frames are created which fit over support posts. As the potatoes sprout and grow a new box frame with fresh soil is added with each layer potatos begin to fill. Once the post can't fit anymore box frames and the plant has fully passed the top the frames are then lifted off and the potatoes harvested.

Here's my current plan pic below

 my idea still remains the same with the box frame concept with 2 different ways the frames go together. The original idea was to do the same support posts on the inside where frames fit over. The other idea was to create box frames that have inserts on the inside so they slot together.

Ideally with the idea with post on the inside you are limited to how many frames can fit due to post height.

where as the idea with slots you have unlimited height.

The build will be done with H3 treated pine (or pine pallets) just because it's outside and the contact with not only the soil but the elements. I did think to line the inside of each box frame with builders plastic to ensure no contact with the soil is made just because of the treated pine but not sure how much the treated pine leaches into soil? 

Has anyone done this before? Anyone got any pros and cons with these? Ideas on the building side etc any ideas would be appreciated 

Thanks yall

MitchellMc

I like your thinking @Dark!

Adding Zenith 150mm Zinc Plated Mending Plates to the outside or inside of the frames would certainly work.

Our H3 outdoor framing timber is treated with copper fixed ACQ (Alkaline Copper Quaternary) waterborne preservatives. ACQ treated pine timber is generally considered safe for use in vegetable gardens. However, you can seal the inside with various materials to prevent the chance of any leaching of chemicals into the soil. Your idea of plastic sounds great or even exterior paint should suffice. There is debate about the health consequences of using arsenic-treated H4 timber, especially around root vegetables. It's generally a good idea to steer clear of that if there are other alternatives available.

I look forward to hearing the opinions of our other keen gardeners. Let me mention @Adam_W, @TheSaltyreefer, @LisasGarden, @mdstorrs, @Grub80 and @mich1972 to see if they have any thoughts.

Mitchell