Thinking about growing sweet potatoes in containers? Even if you’re short on space, don’t worry – pots can be the perfect home for these nutritious vegetables. In this guide, expert gardener Sarah Hyde reveals the art of successful sweet potato cultivation in containers.
Sweet Potatoes: A Garden Gem
More than just a tasty treat, sweet potatoes are a nutritional powerhouse and a vibrant addition to any garden. While they commonly sprawl across garden grounds, many are surprised to discover that these flexible plants can thrive in pots as well. Whether in expansive raised beds or humble garden pots, sweet potatoes are truly versatile.
First-time Pot Planter? Follow These Steps
If you’re new to container cultivation of sweet potatoes, follow this structured approach for a thriving garden.
Step 1a: Finding Sweet Potato Slips
Rather than seeds, sweet potatoes grow from “slips” or plant cuttings. These slips can grow into plants that yield several pounds of sweet potatoes, depending on their type, environment, and harvest time.
Slips are delicate, and they can wither quickly. When you get them, they might look like weak stems with wilted leaves. However, appearances can be deceptive – most of these slips will prosper once sown.
Getting slips requires a bit of planning. Check with local gardening centers early in the season for availability, or order online from trusted seed suppliers. Always order a few extra slips, as some may not survive until planting.
Remember that most suppliers wait until after the last frost to ship, to avoid potential damage to the slips.
Step 1b: Grow Your Own Slips
If you’re only looking to plant a few sweet potato plants, why not create your slips? Start this project indoors early in spring, in a warm, sunny spot.
Begin by placing a ripe sweet potato in a soil-free medium and wait for it to sprout. Treat it with the same care you would any indoor plant. There are numerous methods to initiate sprouting, including placing the potato in water. However, if the water gets murky, you might not enjoy changing it. Both water and soil-free mediums work – choose what fits best for your setting.
Do note: buying sweet potatoes from grocery stores for sprouting may not always work, as they might have been treated to prevent sprouting.
Step 2: Choosing the Right Container
Given that sweet potatoes enjoy stretching their roots deep, your container should be at least 12” deep and about 2 feet wide for each plant. A smaller container might limit your yield.
Ensure your chosen pot provides adequate drainage, either through base holes or well-draining soil for raised beds. Proper drainage is crucial for the health of the tubers. Typically, it’s best to grow one plant per container.
Step 3: Feed Your Sweet Potatoes with Nutrient-Rich Mix
Sweet potatoes thrive when supplied with the right nutrients. Opt for a balanced vegetable fertilizer, preferably with a composition like 10-10-10. If you’re leaning towards organic fertilizers, remember they usually have lower N-P-K numbers such as 2-2-2 or 5-5-5, denoting a lesser nutrient density.
With this in mind, you might have to supplement with organic fertilizers periodically. Always follow the recommendations on the label for how much and how often to apply.
Step 4: Get Planting Posthaste
Plant your slips as soon as the danger of frost has passed. If you’re buying them, suppliers typically ensure they aren’t shipped during frost-prone periods. For homegrown slips, clip them just a day before you intend to plant, allowing the cut end some time to air out.
Upon preparing or receiving your slips, immerse them in the soil without delay. Ensure you water them immediately, especially if they’ve endured a long transit. Give them a few days, and most should recover, showing fresh green growth.
If any slip doesn’t show signs of life after a week, it’s probably best to replace it.
Pro-tip: To increase your chances of success, plant 2 or 3 slips per pot and then relocate or prune the extras later on. If you’re using larger containers, allow about 18” space between slips.
Step 5: Protect Your Plants from Hungry Critters
Both deer and rabbits find sweet potato greens irresistible. Think of ways to shield your garden treasures from these hungry visitors. An occasional sampling won’t harm your plant significantly, but these creatures can feast without limits, which might jeopardize your plant’s growth.
Step 6: Hydration is Key
Potted soil dries out faster than garden beds. Before watering, do a simple moisture check by inserting your finger up to the second knuckle into the soil. If it feels dry, it’s time to quench your plant’s thirst. Avoid over-watering and ensure the container provides sufficient drainage.
Step 7: Harvest Before the Frost Hits
Ease off on watering as harvest time approaches. Sweet potatoes are susceptible to frost, so it’s a good idea to harvest just before the cold sets in. Keep an eye on the forecast and harvest if soil temperatures look set to fall below 55°F, especially crucial for potted sweet potatoes.
When the day arrives, trim the foliage, leaving a few inches for handling. Visualize the growth pattern to minimize damage during extraction. The tubers typically sprawl about a foot from the main stem.
Step 8: The Post-Harvest Curing Ritual
After harvesting, avoid direct sunlight and keep them sheltered during cold nights. Before storing, sweet potatoes need to undergo curing, a process that dries their skin, ensuring a longer shelf life.
Creating the ideal environment for curing, which is 80 to 90°F with 85% to 90% humidity, might be challenging. But even if conditions are less than ideal, with a little patience, the process can be successful.
Once cured, store your sweet potatoes at around 60°F. A well-ventilated basement is usually perfect.
The journey from procuring or growing slips to finally harvesting sweet potatoes is a rewarding one. Not only will you be rewarded with delicious, home-grown tubers, but the lush greens can be a culinary delight too. Following these steps, your container-grown sweet potatoes will provide both a feast for the eyes and the palate. Enjoy!