Growing sweet potatoes always seemed a bit intimidating to me. I’d look at those sprawling vines and think, How on earth can I manage that in my small garden? But then I stumbled upon a brilliant trick: growing sweet potatoes in soil bags. Let me tell you, it’s been a game-changer.
Not only does this method save space, but it’s also surprisingly easy and perfect for anyone who doesn’t have a lot of room to spare. Plus, there’s something so satisfying about harvesting your own sweet, earthy potatoes straight from a bag. If you’ve ever wanted to give it a go, here’s my step-by-step guide to getting it right the first time.
Step 1: Choose the Right Soil Bags
When I first started, I had no idea what kind of bags to use. I’ve since learned that breathable fabric grow bags are the way to go. They allow proper drainage and prevent the soil from becoming waterlogged, which is crucial for sweet potatoes.
You can find grow bags online or at garden centres, and they come in various sizes. I went with 40-litre bags, which gave the sweet potatoes plenty of space to grow. If you’re on a budget, you could even repurpose sturdy sacks or shopping bags, as long as they have drainage holes.
Step 2: Prep Your Soil
Sweet potatoes aren’t fussy, but they do have one non-negotiable: well-draining, loose soil. I made the mistake of using heavy garden soil in my first attempt, and let’s just say the results were… underwhelming.
For the best results, mix your own blend. I combine:
- 1 part compost (for nutrients)
- 1 part sand or perlite (for drainage)
- 1 part garden soil or potting mix
The goal is a light, crumbly texture that lets the roots spread easily.
Step 3: Start with Healthy Slips
Sweet potatoes don’t grow from seeds—they grow from “slips,” which are sprouts that come from a mature sweet potato. You can buy slips from a nursery, but I decided to make my own because it’s cheaper and oddly fun.
Here’s what I did:
- I placed a few organic sweet potatoes in a jar of water, half submerged.
- Within a couple of weeks, sprouts started appearing.
- Once the sprouts were about 6 inches long, I gently twisted them off and placed them in another jar of water to grow roots.
It was amazing watching those roots develop—it felt like a little science experiment!
Step 4: Plant the Slips
Once the slips had a good set of roots (about a week later), it was time to plant them. I filled my grow bags two-thirds full with my prepared soil mix, then planted the slips.
Here’s the trick: bury them deep, leaving just a couple of leaves above the soil. Sweet potatoes grow from underground stems, so the deeper you plant, the more room they have to form. I spaced mine about 10 inches apart, which worked well.
Step 5: Water and Feed Consistently
This is where I learned the importance of balance. Sweet potatoes need consistent moisture, but they hate soggy roots. I watered deeply about once a week and checked the soil regularly. If it felt dry about an inch down, it was time to water.
For feeding, I used a balanced fertiliser every few weeks. Be careful not to go overboard with nitrogen, though—it’ll give you lots of leaves but fewer potatoes. (I learned that the hard way!)
Step 6: Keep Them Warm and Happy
Sweet potatoes are sun lovers, and they need plenty of warmth to thrive. I placed my grow bags in the sunniest corner of my garden, where they got at least 6–8 hours of sunlight a day.
If you’re in a cooler climate, you might need to start them indoors or use a greenhouse. I’ve even heard of people wrapping their grow bags in bubble wrap for insulation—it’s not the prettiest solution, but it works!
Step 7: Harvest with Care
After about 4–5 months, the vines started to yellow and die back, which is the sign that it’s harvest time. This was the most exciting part—I felt like a kid digging for buried treasure!
To avoid damaging the potatoes, I tipped the bags gently onto a tarp and sifted through the soil. The sweet potatoes were there in all their glory—smooth, plump, and beautifully orange. I was ridiculously proud of them, like they were my own little masterpieces.
Why You Should Try This
Growing sweet potatoes in soil bags is one of the most rewarding gardening projects I’ve ever done. It’s low-maintenance, doesn’t require much space, and produces a surprisingly good yield. Plus, there’s something so special about cooking with food you’ve grown yourself. The first batch I harvested went straight into a roasted vegetable tray bake, and they were the sweetest, creamiest sweet potatoes I’ve ever tasted.
If you’ve been hesitating to give it a try, don’t! Grab some grow bags, prep your soil, and get started. Trust me, you’ll be hooked. And when you pull those first sweet potatoes out of the soil, you’ll feel that same thrill I did—the joy of growing something wonderful with your own hands.