Sweet potatoes originally hail from South America, which means they are total heat-seekers! If you want a successful harvest, you’ve got to keep that in mind when picking a spot in your garden. These plants absolutely thrive when they’re soaking up plenty of sunshine.
Keep it Sunny and Warm
Since they belong to the morning glory family, sweet potatoes love a sunny location. While they do appreciate moderately moist soil, they’re actually pretty smart—their trailing vines create a natural mulch that shades the ground, helping to prevent evaporation. This dense growth can make it a little tricky to find the perfect companion plants for sweet potatoes, but herbs that love the sun just as much—like chamomile or dill—are usually great neighbors.
As for the soil, aim for something nutrient-rich, loose, and well-draining. This gives the roots plenty of room to stretch out and develop those big, beautiful tubers we love to eat. If your garden has heavy clay or rocky soil, your sweet potatoes might struggle. In that case, you’re much better off planting them in a raised bed or a large container.
Growing in Pots and Window Boxes
The good news is that sweet potatoes do fantastic in containers! Just make sure your pot holds at least 15 gallons (about 60 liters) to give them enough breathing room. Technically, you could plant them in a window box, but they won’t have enough space to grow decent-sized tubers. Window boxes are better suited for ornamental sweet potato vines. These varieties look stunning with their colorful foliage, but they don’t really produce much in the way of edible roots.
When growing in pots, drainage is the name of the game. You definitely want to avoid “wet feet” (standing water), so make sure your container has plenty of drainage holes. For an extra safety net, add a layer of coarse gravel or lava rocks at the bottom—just remember that if you do this, you’ll need a slightly larger pot to make up for the lost soil space.
Harvest Before the Frost
Sweet potatoes are definitely not fans of the cold—they have zero tolerance for frost. If you have them in a sheltered spot like a balcony, they might hang on a little longer, but you absolutely must dig those roots up before the first frost hits.
Pro tip: Starting in September, you can take cuttings to propagate your plants for next year. This is a great way to “overwinter” your sweet potatoes. Propagation is super easy—just take a cutting about 8 inches long and pop it in some water. Roots will sprout from the leaf nodes, so make sure at least one node is submerged. They grow roots so fast that you’ll usually be ready to pot them up in soil after just a few days!
