A New Garden Idea and Question

Today, I was able to begin and somewhat finish a simple garden pot idea that has been bouncing around in my head for days. After my plant shopping, I have ended up with 11 tomato plants. Oy. Way too many for this deck gardener, so I will do my best to parcel some of them out before they wilt and fizzle away. But for those that will eventually produce our food, I needed to find an inexpensive and suitable way to pot them up, bearing in mind they will be on our deck. I know that tomatoes do best when planted deeply, so knew that what I had was not going to work - plain terra cotta pots and such. What I came up with was this:

A simple Home Depot bucket, food grade, to transform into a glorious tomato pot.  It set me back a mere $2.78.

First, I primed it with plastic primer spray paint:

Then I used a hammered copper spray paint over the primer.  I tried to get some of the orange to disappear on the inside, but it was starting to rain, so I rushed it a bit:

I really like the copper look, don't you?  I mean, clearly, it's not a copper pot, but it does make you stop and look twice.  Here is the planted version:

I put the handle back for easier move-ability.  I purchased four of these buckets today, hoping to get them all planted (and not realizing I had 11 tomato plants).  I painted and planted only 2.  So tomorrow, my goal is to find homes for at least 4-5 plants, and then by the weekend, have the rest planted, either in more painted buckets, or other tremendously creative ideas.

Now for my gardening question.  I have planted sweet potato vine, since I absolutely love the colors it has.  My problem, that I have never experienced before, is that the green is turning purple.  I have no idea why.  

It is happening to all of my sweet potato vines, in each container I've planted them in.  The only constant is the same organic compost/soil mixture which may possibly be a bit too rich in compost.  I had thought this was a sign of comport burn, but now we're just changing colors.  Any thoughts or ideas out there?  Any sweet potato vine experts out there?  Drop me a line/comment and help a garden girl out, won't ya?