Growing sweet potatoes from seed isn’t exactly the standard way to go, but it’s a fun challenge if you’re up for it! Just a heads-up: it takes a lot of patience, and finding quality seeds can be tricky. You usually won’t find them at your local garden center, so you’ll likely need to hunt them down from international sellers online.
Harvesting Your Own Seeds
While sweet potatoes often bloom in late summer in our backyard gardens, our growing season usually isn’t long enough for those seeds to actually ripen. In theory, they could produce seeds here since they can be both cross-pollinated or self-pollinated, but the clock usually runs out before they’re ready.
What to look for in real seeds:
- 1 to 2 seeds per seed pod
- Deep black color
- Rounded shape
- About 3 mm long
- Smooth texture
- Very hard shell
If you’re ordering online, double-check that the seeds match this description. Since exotic plants are trendy, some sketchy sellers might try to sell you “look-alike” seeds at a premium price. Stick to reputable sources!
The Long Wait for Germination
If you decide to go the seed route, get ready for a long growing journey. Sweet potato seeds have an incredibly tough, waterproof shell. This “armor” keeps water and oxygen out, which means the little seedling inside stays dormant and won’t start growing on its own.
You can give your seeds a little “jumpstart” by scarifying them—basically, rub them gently with some sandpaper. This thins out the shell so water can get in and the sprout can break through more easily. After sanding, soak them in warm water for 24 hours. Pro tip: keep the water warm by placing the container on a warm spot, like the top of your refrigerator.
Sowing Your Sweet Potatoes
Sweet potato seeds have a notoriously low germination rate, so don’t be discouraged! To have plants ready for the garden by mid-May, you’ll need to start the germination process as early as January. Don’t panic if nothing happens right away—it can take over four weeks just to see those first little leaves.
How to plant them:
- Fill a pot with high-quality veggie potting soil.
- Press the seeds about 1 inch (2–2.5 cm) deep into the soil.
- Firm the soil down gently.
- Give them a good watering.
I recommend planting them directly into nutrient-rich soil from the start so you don’t risk damaging the sensitive young roots during transplanting. Once the danger of frost has passed in mid-May, you can move your sweet potatoes into the garden bed or plant them in large outdoor containers. Happy planting!
