Cast iron tub

Hello all!

So, I have an old cast iron enameled bathtub that I was originally going to partially bury and plant sunchokes in to contain them. We grew sunchokes in smaller buried tubs last year and, although they grew well, they molded in storage (possibly my fault).

We grew sweet potatoes in a hugelkultur mound last year and it was obvious that the tubers hit branches and whatnot in the mound and grew twisted and contorted. But, they stored excellently from last fall and still look great now.

The goal is not only to grow root crops, but also to store them for winter use. Both the sunchokes and sweet potatoes grew well but only the sweet potatoes stored well. Plus, given the fact that these relatively new hugelkultur beds gave the sweet potatoes too many obstacles, I’m wanting to grow them elsewhere.

So, what do you all think? I’m considering filling the tub most of the way with good, loose soil and growing the sweet potatoes in there. My questions are, should I bury it or leave it above ground? We’re in zone 4, so short cool growing season. Which means sweet potatoes will need plastic mulch to retain heat and moisture. Would burying the tub keep it warmer or would giving it full sun keep it warmer? The outside is all rust now, but I’ve considered sanding it off and painting it black if that would help.

sunchokes store best in the ground, which i guess you learned.

i would think the sweet potatoes would stay warmer with a tub that’s not dug into the ground. painting it black would definitely help, too.

greg mosser wrote:sunchokes store best in the ground, which i guess you learned.

i would think the sweet potatoes would stay warmer with a tub that’s not dug into the ground. painting it black would definitely help, too.

I wasnt sure how to keep the sunchokes from freezing in the ground in winter. We’re in zone 4 here. Probably would need a couple bales of straw on top of them to insulate.

I stored them in sand, but realized the sand was dry so dampened it and covered it with plastic. That just made them rot...

Keep it it full sun it'll be a lot warmer that way. you can keep Jerusalem artichokes in damp sand very well (keeping in the ground is not possible here) you don't need to put plastic over the sand, just check on it every month or so.

Skandi Rogers wrote:Keep it it full sun it'll be a lot warmer that way. you can keep Jerusalem artichokes in damp sand very well (keeping in the ground is not possible here) you don't need to put plastic over the sand, just check on it every month or so.

Yea, I figured the plastic over the top did them im. I’ll probably try again this fall but without the plastic.

I tried growing various vegetables & flowers in an old cast iron tub the past few years. Above ground. Early in the season it seemed to work good for an early crop of peas but later in the season it got too hot & everything died. I use it now for mulching weeds with seeds.

Mike Barkley wrote:I tried growing various vegetables & flowers in an old cast iron tub the past few years. Above ground. Early in the season it seemed to work good for an early crop of peas but later in the season it got too hot & everything died. I use it now for mulching weeds with seeds.

What climate/zone are you in? We’re zone 4 temperate climate here and I think the warmer the better for growing sweet potatoes here! Maybe the tun would be perfect.

I'm in zone 7. I think a cast iron tub would be much more useful in zone 4. Sweet potatoes do love the heat.