I have never grown sweet potatoes. Last year I wanted to buy some slips, but first the many varieties and growing needs gave me too many options, and my timing was off anyway.
Last week a friend gave me some sweet potatoes from NC that are not supposed to be stringy, so I decided to try and grow my own slips from some of them. I DO remember my grandma putting a sweet potato in a glass bottle on the windowsill, and it produced a lovely plant. However, I was too young to know if she was starting slips, or just a pretty indoor plant.
So I dinked around the internet for how to start my own slips and decided to go for it. Shown in the photo above is a shallow pan, and a seed starting mix with an equal amount of sand mixed with it. Optimally, I'd have a box outside like a cold frame, and some fresh manure in the bottom to generate heat. Since I do not, this is my best idea for a substitute.
I read that sweet potatoes need temps above 80ºF to germinate... and I can't remember if any of my sweet potatoes ever grew roots when stored in the kitchen bin the way white potatoes and onions do. I think I might remember if they did. Of course many potatoes, including sweet potatoes, are treated against germination before they hit the grocery store shelves.
I covered the sweet potatoes (a deeper pan would have been better), wet the soil down thoroughly, and brought it into the house where I placed it on an electric seed starting heat mat, and covered the top with plastic wrap and a towel to contain the heat and moisture.
I have no idea whatsoever if this will work, but I will be sure to report any success or failure!