Interesting.. how would you harvest? I'm having a hard time picturing it in my mind, but it sounds cool.

gnomey - I was wondering the same thing only I thought I was being dumb so I didn't ask. I don't feel so bad now :-)

Val

You would harvest it by opening the structure up or lifting it off somehow. Still not sure what the best design for something like this would be, but the simplest thing would just be a ring of chicken wire .

I got the idea from 'potato towers' that people build.

You can check out the idea here:
http://www.youtube.com/watch?v=2xbUI6Y18pY

The idea I have is to have something like that except it will be filled from the start and there will be holes/openings all along the side (not enough for the soil to come out, but enough for the sprouting plants to make it out of the structure).

I'm guessing I would need very light soil for it to work, which I think is good for most of these root crops anyway). I think it has potential

I have grown potatoes in nothing more than a pile of leaves with some compost added, sometimes contained in a circle of fencing, and that was all that was needed to get a good harvest. One advantage is that you can start harvesting the potatoes fairly early by reaching into the leaf pile, not removing or otherwise disturbing the plant, and pluck a few potatoes for dinner and the plants keep producing more. I'm not sure about the other root crops since I never tried them.

I grew potatoes last year in a large rubbermaid roughneck storage bin. It turned out well.

I drilled drainage holes in the bottom, added a layer of straw (maybe an inch), a little soil and peat moss and put the sprouts in. As I needed, I added peat moss/soil mixture to bring the level up. At the end of the year I dumped the bin over and harvested my potatoes.

Two things I read when researching were not to add composted manure because it would increase the incidence of scab, and lowering the pH because this would reduce problems with your potatoes. I chose peat moss because this would help with the pH in the bin and made for a nice fluffy growing medium. You can reach down into the bin and grab a growing potato or two if you don't want to harvest all at once.

Hope this helps!

The problem of having it 'filled from the start' would be that you would lose the advantage of a potato tower which is that by placing the seed potatoes near the bottom and then constantly filling with soil/compost to bury the stems as they grow you get a very large,deep crop of tubers. If you just put the potatoes in a full tower there is no advantage over growing in the ground. This treatment would not suit the other root crops you mention (I know nothing about yams btw.)I also think you would run into trouble trying to mix all those roots together. They have different requirements, days to harvest and growth habits. They can all be grown in containers but there would be no advantage to growing any of them in a tower other than the potatoes. I may be proved wrong but I don't think they would enjoy being grown through holes in the sides as strawberries and some herbs can be. I have a feeling you'd end up with some strange shaped carrots!

A 30 second net search did not reveal much. Maybe one of the commercial sellers could reccommend the best soil mix.

Here is a link that might be useful: Ben's Potato Tower

Back in the 1960's or 1970's Organic Gardening magazine, Mother Earth News, and probably Countryside and other of the "back to the land" magazines had articles on growing potatoes this way. I doubt that it would be necessary to spend that much money on something to contain the growing medium since I had very good results with 2 x 4 mesh welded wire fence.

I've also seen references to using recycled tires to do the same sort of tower. Since your siggy is that of a Canuck, this might be of real interest to you! Colder there than where I am!

Here is a link that might be useful: Using old tires in the garden

As Flora points out, growing different vegetables and or fruits together usually turns out badly. The different vegies have different requirements of watering, fertilizing, growing, harvesting, sun-needs and other barriers to good growing conditions.

Try to grow same family vegetables together for better results.

Not necessarily used for tubers but they use bag gardens in Africa. It's an easy way for children to raise their own veggies.

Check out the Send a Cow web page.

Here is a link that might be useful: Bag gardens

There are those that advocate using old tires in the garden and then there are those of us that emphatically state they should not be. My experience is that where tires were dumped the soil under those tires had levels of heavy metals high enough that the environmental protection people required that soil to be removed to a hazardous materials landfill. The New York Times has had a series of articles about children playing on artificial turf (made with shredded tires) and playgrounds covered with shredded tires having elevated levels of carcinogens in their urine and blood.
Probably using tires to grow food would not be a good idea.

Interesting link shebear...nice to see the kids doing some vertical gardening. I think Kimmsr makes a good point about pollutants in old tires...I would be very wary about it using tire to build a crop tower...I would rather spend a bit and have a wire or wood structure...or even a bag garden like shebear linked to.

I have to give some thought as to what crops I can stick together..there's so many root crops out there.