How to Grow Sweet Potatoes in Containers: Complete Guide

What delicious things would you cook if you could grow sweet potatoes at home? Salty sweet potato fries, creamy buttered mashed sweet potatoes, or maybe sweet potato casserole?

You may be surprised to learn that anyone, anywhere can plant and grow a sweet potato vine. Sweet potatoes are super fun to grow; they don’t attract many pests, look beautiful in containers, and still provide a harvest of food at the end of the season.

It won’t take long for sweet potatoes to become your favorite plant to grow! I’m going to teach you how to grow sweet potatoes in containers, with a bonus YouTube video on how to grow your own sweet potato slips from store-bought sweet potatoes. 

Superfood or Ornamental Wonder

Sweet potato vines are a popular ornamental foliage plant. You’ve probably seen the bright green, heart-shaped leaves spilling out of beautiful containers and planters.

You may not know that the tubers are also considered a superfood! With antioxidants, fiber, and essential vitamins and minerals, they are a healthy addition to any diet.

I love having delicious, nutritious food to fill my table. Sweet potatoes fit that bill, along with summer squash and winter squash varieties, tomato plant varieties, types of lettuce, types of garlic, and so many other plants you can grow at home. 

Best Variety of Sweet Potatoes for Growing in Containers

The most crucial consideration for selecting which variety of sweet potato to grow in containers is finding a variety that grows well in your local area! Sweet potatoes are tropical plants, so it may take some research and asking around to find varieties that will do well in the climate you live in.

There are two varieties that do really well for me growing here in Michigan every year: Georgia Jet sweet potatoes and Beauregard sweet potatoes. They both produce well in our shorter growing season that doesn’t have much of the hot, humid weather sweet potatoes normally like.

The second consideration is this: sweet potato vines will set down roots all along the stem as they vine out. Some varieties will produce tubers everywhere these roots touch the ground. When growing in containers, I prefer a variety that doesn’t do that, so I only end up with tubers growing in my container rather than all over in my mulch on the ground. But you choose whichever type suits your growing style.

How Much Space Do Sweet Potato Plants Need

The typical spacing for sweet potatoes in raised garden beds or in-ground gardens is one plant every 2 to 3 feet. Some people are hesitant to grow sweet potatoes in containers because they fear the plants will be too crowded. Surprisingly, sweet potatoes actually like to be slightly cramped for space. 

There is a Goldilocks scenario here. You don’t want them too cramped, or they will suffer for adequate water and nutrients, leading to smaller yields and smaller sweet potatoes. But if you give them too much space, you won’t get good yields either. You want to find the “just right” conditions somewhere in the middle.

The Right Container to Grow Sweet Potatoes

To provide the “just right” amount of space for growing sweet potatoes, the first thing you want to get right is the size of the container! It’s important to make sure you have a large enough container for the number of sweet potatoes you plan to grow.

The minimum container size for growing sweet potatoes is a 10-gallon container (37.85 liters). That size is good for growing ONE sweet potato plant.

To grow two sweet potato plants in a single container, you will need a 15-gallon container (56.78 liters). If you want to grow three plants in a single container, like I do in the video, you will want a 20-gallon container (75.71 liters).

I highly recommend using fabric grow bags for growing sweet potatoes and other container gardening. They are awesome, and I love growing in them!

Best Soil For Growing Sweet Potato Plants

Choosing the right type of soil is vital, but you don’t have to spend a bunch of money to get it! Prioritize these three main things when choosing your potting soil:

• Porosity - Porosity is a measure of how spongy and porous the soil is, and it helps the soil hold onto the right amount of water. The less porous your soil is, the more watering it will require. Sweet potatoes will benefit from a more porous soil because they like lots of water to form nice, big roots.

• Aeration - You want good aeration in the soil because it will drain away excess water which improves oxygen exchange for the roots, helps the roots develop faster, and helps roots not to rot. Pro-Tip: Perlite is a lightweight, inexpensive additive that helps improve soil aeration.

• Fertility - Most potting soils don’t contain a lot of fertilizer, but you want to give your sweet potatoes as much nitrogen as possible! You may be thinking that a sweet potato is a tuberous root and therefore needs phosphorous for development, but you actually want to fertilize for leaf development because growing lots of foliage will help encourage larger roots.

I use a good all-purpose potting mix (Pro-mix) and add perlite.

Fertilizing Sweet Potatoes

My go-to fertilizer for my entire garden is Trifecta+. It is, by far, the best fertilizer I have ever used. Fertilize sweet potatoes twice a year: at planting and again midseason when they start to flower (this is when tuber development begins).

When considering how much fertilizer to use, I recommend overfertilizing sweet potatoes. I can already hear some of you gasping! Why would I ever “overfertilize”?

The reason is that we are crowding three sweet potato plants into a small-ish container that is full of sterile potting mix (it has no fertility of its own to begin with). Crowding these plants a little maximizes yields, but we need to increase the fertilizer to avoid creating too much competition for nutrients.

Typically, I would fertilize sweet potatoes about ¼ cup per plant. That may not seem like much, but Trifecta+ is very concentrated, so a little goes a long way. However, I have increased that to ½ cup of Trifecta+ per plant when planting in containers (or 1 ½ cups in my 20-gallon container). 

Growing Your Own Sweet Potato Slips

Sweet potato slips are root sprouts grown from a mature sweet potato that you plant at the beginning of the season to grow sweet potatoes. You can buy slips or grow your own. 

Good news, if you want to grow your own, they are really easy to start! Check out the video above to learn how to make your own sweet potato slips to save money and have fun at the same time!

How to Grow Sweet Potatoes in Containers

1. Fill Containers With Soil - Fill your container most of the way with potting soil (adding perlite and fertilizer as described above). Pro-Tip: It is a good idea to pre-moisten your soil to reduce transplant shock. You know you have the correct amount of moisture in the mix if you can take a handful and squeeze it very hard, but only a few drops of water come out. If no water drips out, add a bit more water.

2. Test Soil pH - Sweet potatoes like a slightly acidic soil with a pH of 6.0 to 6.5. Whenever you plant sweet potatoes, test the soil pH. If the soil is alkaline, add some soil sulfur. (Fertilizers like Trifecta+ will also alter the pH to make it slightly more acidic.)

3. Provide Adequate Sunlight - The great thing about containers is that you can move them wherever you want. Sweet potatoes need lots of sunlight, so put them in a location that will get nice, full sun. Five hours of direct sunlight is the bare minimum. I prefer to give them 7 to 9 hours of direct sunlight. The more sunlight you give them, the larger your harvest of sweet potatoes will be. 

4. Plant Spacing - Dig one hole in your container for each slip you plan to plant. The holes should be large enough for the root balls and evenly spaced to give each sweet potato room to grow.

5. Plant Slips - Plant a sweet potato slip in each hole at the same depth it was in the starting container. 

6. Water - Thoroughly water after planting and continue watering frequently. Not only do containers require more water, but your potting soil should be very well-draining. To make sure your plants are getting adequate water check frequently. Stick your finger down into the soil about 2-3 inches; if the soil is not damp, give them some water. Pro-Tip: If you are using grow bags, plan to water about twice as often as you would with standard pots because they are more breathable.

7. Humidity - Sweet potatoes do love a humid environment, thriving in 80% or 90% humidity. I know you can’t control the outside humidity, but I find that my sweet potatoes do the best in late August through early September when the weather is nice and hot and muggy.

8. Space - Sweet potatoes need space; the larger you let the plants get, the more energy they produce and the more you will harvest. They are vines that will trail and go crazy like a cucumber or squash. By the end of the season, my three plants should have grown about 10 feet in either direction. Make sure there is adequate space around your container so the vines will not interfere with foot traffic or your other garden plants.

Don’t worry if they seem like a huge mess above ground, and don't prune them back. The important thing when growing sweet potatoes for food is not what happens up top, but what happens below the surface. 

Harvesting Sweet Potatoes

Sweet potatoes are different than regular potatoes, which will eventually stop growing and die back. Instead, sweet potatoes continue to grow as long as the weather allows. So in theory, I could grow them from early April until early October.

I like to harvest my sweet potatoes when the nights start to get cool and damp, to reduce the risk of rot. Harvest time is so exciting because you never really know what you're going to get!

To harvest sweet potatoes, simply turn the container over and dump the contents out. Gently dig through the soil until you find all of the tubers. 

Put the sweet potatoes in a cardboard box and place the box in a warm room (like a boiler room), preferably above 80°F. Leave them for at least 2 to 4 weeks to cure. This step is very important because this is when the sugars condense, giving them their flavor. If you skip curing, your sweet potatoes will taste bland.