Sweet potatoes are a fantastic crop for gardeners of any skill level. They are nutritious, store well, and can produce a huge harvest from just a few plants. If you’ve wanted to try growing your own, you’re in the right place. This is a simple guide on how to grow sweet potatoes – easy step-by-step guide.
You don’t need a huge farm to be successful. With some sunshine, warm soil, and a little patience, you can grow sweet potatoes in garden beds, raised beds, or even large containers. Let’s get started with everything you need to know.
How to Grow Sweet Potatoes – Easy Step-by-Step Guide
The process is straightforward. We’ll break it down from choosing your plants to harvesting your crop.
Starting with “Slips”: Don’t Use Store-Bought Tubers
You begin with “slips,” which are small rooted sprouts. It’s tempting to just plant a sweet potato from the grocery store, but I don’t recommend it. Those varieties might not suit your climate, and they can carry disease.
You have two easy options:
* Buy Slips Online: This is the easiest method. Many garden suppliers sell healthy, disease-free slips of proven varieties. Order them a few weeks before your planting date.
* Grow Your Own Slips: It’s a fun project! About 6-8 weeks before your last frost, suspend half a sweet potato (use an organic one) in a jar of water using toothpicks. Place it in a warm, bright window. Soon, leafy slips will grow from the top. Once they’re 6-10 inches tall, you gently twist them off and root them in water.
Choosing the Perfect Variety
Picking the right type makes a big difference. Sweet potatoes come in different flesh colors and maturity times.
* Orange-Fleshed (like ‘Beauregard’ or ‘Georgia Jet’): These are the classic, moist types. They are often faster maturing, which is great for cooler climates with shorter summers.
* White/Yellow-Fleshed (like ‘Japanese’ or ‘Boniato’): These have a drier, flakier texture and are slightly less sweet. They often need a longer, hotter growing season.
* Purple-Fleshed: These are stunning and packed with antioxidants. They typically require the longest, warmest season to develop fully.
Check with your local nursery or extension service for the best varieties in your area.
Preparing Your Garden Bed
Sweet potatoes love loose, well-draining soil. They will struggle in heavy, compacted clay. The goal is to create a soft, fluffy bed for the tubers to expand easily.
Here’s how to prepare:
1. Choose the sunniest spot in your garden. They need at least 6-8 hours of direct sun daily.
2. Loosen the soil deeply, at least 12 inches down.
3. Mix in a few inches of compost. Avoid high-nitrogen fertilizers, as they will give you huge vines but tiny tubers.
4. Form loose, mounded rows or hills. This improves drainage and warms the soil faster.
Planting Your Sweet Potato Slips
Timing is crucial. Sweet potatoes are tropical plants and hate cold. Plant them at least 2-3 weeks after your last spring frost, when the soil is consistently warm (above 65°F is ideal). A cold snap can stunt them for weeks.
The planting process is simple:
1. If your slips arrived by mail or you rooted them in water, harden them off for a few days by placing them outside in a shaded, protected spot.
2. Water the slips well before planting.
3. Make a hole deep enough to bury the roots and most of the stem. You can plant them horizontally in a shallow trench if you like, but burying the stem nodes encourages more rooting.
4. Space slips about 12-18 inches apart in rows that are 3-4 feet apart. They need room to sprawl!
5. Water them in thoroughly to settle the soil.
Care Through the Growing Season
Once established, sweet potatoes are remarkably low-maintenance.
Watering Wisely
Water regularly for the first few weeks to get plants established. After that, they are quite drought-tolerant. Deep, infrequent watering is best. Reduce watering significantly during the last 3-4 weeks before harvest. This helps the potatoes cure and develop their sweetness.
Weeding (But Only at First)
Keep the area weed-free when the plants are young. Once the vines spread and create a dense mat, they will shade out most weeds on there own. Be careful not to disturb the shallow roots near the plant crown when weeding.
To Fertilize or Not?
As mentioned, go easy on fertilizer. If your soil is poor, a side dressing of a low-nitrogen, potassium-rich fertilizer (like a 5-10-10 blend) a month after planting can help. But often, the compost you added at planting is plenty.
Harvesting Your Sweet Potatoes
This is the exciting part! Your potatoes are ready to harvest about 90-120 days after planting, depending on the variety. The key sign is when the leaves start to yellow, usually around your first fall frost.
Crucial Tip: You must harvest before the soil temperature drops below 50°F, as cold soil can damage the tubers.
Follow these steps for a good harvest:
1. Choose a dry day. Use a garden fork, not a shovel, to avoid spearing tubers.
2. Start digging about a foot away from the main plant crown, loosening the soil carefully.
3. Gently lift the vine and use your hands to sift through the soil for the tubers. They can be surprisingly far from the plant!
4. Handle them gently. The skin is very thin and easily bruised at harvest.
Curing and Storing for Longevity
This final step is non-negotiable if you want sweet, storable potatoes. Freshly dug sweet potatoes are not very sweet and won’t keep.
* Curing: Place unwashed tubers in a warm (80-85°F), humid place for 10-14 days. A shaded outdoor table or a warm bathroom works. This process heals minor wounds and converts starches to sugars.
* Storing: After curing, brush off any dry dirt (don’t wash them). Store them in a cool (55-60°F), dark, and well-ventilated place. Properly cured and stored sweet potatoes can last for 6 months or more!
Growing in Containers
No garden? No problem! Sweet potatoes grow very well in large containers.
* Choose a pot that holds at least 20 gallons, like a half whiskey barrel. Make sure it has excellent drainage holes.
* Fill it with a light, potting mix (not garden soil).
* Plant 1-2 slips per container.
* Place it in full sun and water regularly, as containers dry out faster.
* The vines will trail beautifully over the sides.
FAQ: Your Sweet Potato Questions Answered
Can I grow sweet potatoes from a whole potato?
You can start slips from one, but planting a whole store-bought tuber directly in the garden usually leads to crowded, misshapen potatoes and potential disease issues. Starting with individual slips is always better.
Why are my plants all vines and no potatoes?
This is usually caused by too much nitrogen in the soil, planting too early in cold soil, or not allowing enough growing days for your variety. Also, overwatering late in the season can hinder tuber development.
What are the main pests to watch for?
Deer and rabbits might munch on the vines. Underground, voles and mice can sometimes be a problem. The most common insect pest is the sweet potato weevil, primarily in southern climates. Rotating your crop location each year helps manage pests.
When is the best time to plant sweet potato slips?
Plant them in late spring or early summer, when both the days and the soil are reliably warm. This is well after the danger of frost has passed for your area.
How do you grow sweet potatoes successfully in cooler climates?
Use black plastic mulch to warm the soil, choose a short-season variety (like ‘Georgia Jet’), and consider using a cold frame or growing them in a container you can move to a sheltered spot. Every bit of extra heat helps.