Annie 
This is the time of year when I propagate my momma sweet potato plants by taking clippings and making baby sweet potato plants. Now you might ask, how do I get a momma sweet potato plant? Fortunately, it’s easy:
- In the late winter or early spring of your first year growing sweet potatoes, go to your favorite organic grocery store (my go-to in Des Moines is Gateway Market, hands down) and purchase a few of your favorite kinds of sweet potatoes—garnet, white, purple, whatever.
- Slice the potatoes into thick chunks and stick 2 to 3 toothpicks in the edges. Set the chunks, cut side down, over a jar or container filled with water so the bottom of the chunk is dipped in the water. Place near a sunny window and wait for sprouts to emerge (check water level every couple days or so). Some will make sprouts, others won’t. If you see any mold or weirdness on any of them, toss it. As long as you have a few potatoes sprouting, that’s all you need.
- Once the sprouts are about about 2 inches in length, trim them off at the base, dip them in rooting hormone, and nestle them in soil. Keep them well-watered and let them grow until it’s warm enough to plant them outside—about mid-may here in Iowa. (I do this step gradually as the sprouts grow.)
- At harvest time in the late fall (usually just before first frost), dig up your sweet potatoes, then take a clipping of the momma plants. Dip them in rooting hormone as you did in the spring, and plant them in a pot. Keep it well-watered all winter and you will have a momma plant to clip from in the spring.
