Last Updated on October 16, 2025 by Homegrown Florida
Can you really grow a year’s supply of sweet potatoes in a vertical container? That’s what I set out to find this year. For years I’ve been growing sweet potatoes in my raised beds, but as my garden soil has matured and become richer, the harvests have slowly declined. So this time, I decided to compare two methods side by side, traditional raised beds and a GreenStalk vertical planter, to see which one gives the best results for Florida gardeners.
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The Right Varieties for Florida
This season I grew two reliable varieties: Tainung 64 and the classic Beauregard. Both perform well in Florida’s long, warm season, but they grow a bit differently.
The Tainung 64 produced fewer tubers overall, yet they were larger and more uniform even from a single volunteer plant. It’s slightly less vining than the Beauregard, which makes it easier to manage in tight spaces or containers. The Beauregard gave me more potatoes but they were smaller and tended to form earlier. Either variety can work, but if you want to try growing sweet potatoes in a vertical garden, Tainung 64 seems to be the better fit.
Why Raised Beds Started Producing Less
If you’ve gardened in Florida for a while, your soil has probably gotten better over time, more compost, more organic matter, better texture. The problem is that sweet potatoes don’t actually like rich soil. They thrive in sandy, slightly lean soil with good drainage. High nitrogen from compost or fertilizer pushes them to growing sweet potatoes leaves instead of roots.
That’s exactly what happened in my raised beds. The vines grew beautifully, but the harvests were small. So this year I mixed in native Florida sand to bring back some of that lighter texture and it worked better. I still had some root-knot nematode issues, but the yields noticeably improved compared to previous years. The plants in sandier soil clearly formed better tubers.
Starting Sweet Potatoes from Slips
Every sweet potato season starts with slips, the small sprouts that grow from mature tubers. The easiest way to make your own is by taking sweet potatoes from a previous harvest and laying them sideways in your garden bed. Cover them halfway with soil, and after 4 to 8 weeks, you’ll see new shoots emerging.
When the slips reach about six inches tall, cut or gently twist them from the mother potato. Place them in a glass of water for three to five days to form roots. Keep the glass in the shade so the leaves don’t wilt. You can even cut longer slips in half since both ends will root.
This year I clipped my slips close to the potato without breaking the base, which encouraged faster regrowth and gave me more slips in less time. Once the slips form strong white roots, they’re ready to plant.
Setting Up the GreenStalk Planter
For the GreenStalk vertical garden, I filled each tier with a half-and-half mix of sand and low-nutrient soil. I often reuse soil from previous container crops that’s already depleted. The goal is to mimic the light, loose texture that sweet potatoes prefer.
When planting, I use a small trowel to push diagonally into the pocket and insert the slip deep, making sure the roots reach toward the center watering disc. This helps keep the soil evenly moist. I staggered planting one tier at a time as more slips were ready, starting from the bottom. For the first few days, I water generously from the top to help the slips establish. Once they start growing sweet potatoes, the built-in watering system does the rest.
Managing the Vines
In raised beds, it’s easy to let the vines run wild but those vines will root anywhere they touch soil, sending energy into new shoots instead of fattening the main tubers. In the GreenStalk, I use Greenstalk’s lightweight plant supports to wrap the vines around the tower instead of letting them trail to the ground. This keeps them from rooting in other pockets or along the ground nearby and improves airflow, reducing the chance of disease.
Within a few weeks, the lower tiers started vining out aggressively, and by week four, the whole tower was full of healthy green growth. It’s amazing how fast sweet potatoes can take over once they’re settled.
Comparing the Harvests
After about five months of growing sweet potatoes, right in the middle of Florida’s sweet potato window of four to six months, it was time to harvest. I cut all the vines back first and saved a few for cuttings that I’ll root and keep alive through winter for next year’s slips.
From the GreenStalk alone, I harvested about 12 to 15 pounds of sweet potatoes. They were long and slender, shaped more like garden snakes than classic tubers, but still a decent size. The sandy tiers produced noticeably better roots than the richer ones, proving again that leaner soil works best.
For comparison, the raised bed Tainung 64s grew much thicker potatoes, several large, fat roots from just one plant, but fewer overall. The Beauregards made lots of smaller ones. Weight-wise, both systems yielded about the same, but the container setup only used two square feet of space as opposed to 32 square feet of bed space. That’s an easy win for small gardens or patios.
Why Soil Type Makes All the Difference
The takeaway from this experiment is simple: sweet potatoes don’t want rich soil. Too much compost or fertilizer pushes leaf growth instead of roots. Mixing in sand or reusing old soil brings balance back to the growing mix and helps form better tubers.
If your sweet potato harvests have been shrinking over the years, the problem might not be your slips, it’s probably the soil being too good. Try blending in some native sand or recycled potting soil next season.
Curing and Storing Sweet Potatoes
Freshly dug sweet potatoes taste more like white potatoes. Their sweetness develops only after a short curing period. To cure them, lay the roots out in a warm, humid, and shaded area for about two weeks. A garage or covered porch works well.
Keep them off the ground by setting them on cardboard or an old towel, and cover them lightly with a cloth to block sunlight. After two weeks, the skins will toughen and the sugars will concentrate. Then move them into paper grocery bags and store them in a cool pantry. They’ll easily last up to a year this way without sprouting or spoiling.
Final Thoughts
Growing sweet potatoes in a vertical container was a success, not a record-breaking yield, but a solid, space-efficient harvest. The Tainung 64 performed beautifully even in depleted soil, and the GreenStalk made it easy to manage vines without them taking over the yard.
If your raised beds have become too fertile or you’re tight on space, try a sandy mix in a vertical garden. You might be surprised by how much you can harvest from just a couple of square feet. And as a bonus, the vines are edible too; tender, sweet greens that cook like spinach and taste even better.
Growing sweet potatoes are one of Florida’s most forgiving crops once you learn their preferences: lean soil, steady warmth, and a little patience.
