It might be too late to start slips for this year's harvest, Seed. But you could "practice" starting the slips so you will know what you are doing next spring. It took mine forever to start to grow this year, and I had used organic potatoes, so I know they weren't treated. I finally just planted the potato in potting soil. Once they start growing, you can cut off a section of the vine and root it in water, for another plant to put in the garden. Also, I found that you can stick a rootless cutting in the ground, keep it watered, and it will grow as well as the rooted ones.