The subject of sprouting your own sweet potato slips came up on a discussion and I realized I’ve never posted pictures of the method I use. Sweet potato vines are a beautiful ornamental even if you don’t grow them for the tubers. Right about now is when sweet potatoes from the previous year, whether from the supermarket or your home garden, will start attempting to sprout. I have always used purchased sweet potatoes from the supermarket and farmer’s market, and various yams from the Asian market to start my own. I’ve never had the slightest trouble getting them to sprout. It takes approximately 3-4 weeks to produce rooted slips and then you either plant them in pots for a couple more weeks to encourage more roots, or set them directly into the garden. Unlike regular potatoes they cannot handle the slightest bit of cold, so count back 4-6 weeks from the time you’d normally plant things like okra and black-eyed peas and start them then.
To begin with, cut the crown off the tuber, then split it lengthwise down the middle. If it’s an especially large tuber, you may want to cut it into more pieces so they are not so thick and fat. Thicker pieces tend to rot faster than thinner ones. If there is a row of “eyes” down the length of the potato, try NOT to cut directly thru it, as this is where the sprouts form. In this picture, you can see the sprouts already forming on the crown piece.
Now, cut a single sheet of newspaper to fit into a garden flat. Sprinkle a thin layer of potting mix over the paper, then lay your tuber pieces in, cut side down. You can completely fill the flat with slices of sweet potatoes, like this:
Now, put more potting mix over the pieces, burying them completely. Water the flat and keep it in a warm place. On warm, sunny days, move the flat outdoors. (This is when you’ll appreciate not having the pieces in heavy, individual pots!) In 3-4 weeks, this is what you’ll have:
The crown pieces will always sprout first, followed by the eyes along the length of the potato. At this point, you can start breaking off slips and planting in pots or directly into the garden. Once an eye is “spent” that eye will not produce another sprout, but other eyes elsewhere on the tuber may sprout later, so bury them back in the potting mix after you remove the sprouts. Here is what the slips look like after the soil is rinsed away:
Gently snap each rootlet from the tuber to plant. When potting or planting the slips, spread out the roots, cover the whole thing with soil or potting mix, then gently pull up on the plant to the desired height.
In a few weeks, these slips will have a well-developed root structure and will thrive easily in the garden or in flower beds as a beautiful ornamental. Enjoy!