This year’s sweet potato harvest: A poor yield – we think we know the reason

Do you like ordinary potatoes? If so, you’re sure to enjoy sweet potatoes too. These slightly sweet tubers are prepared in much the same way as potatoes; you just have to get used to that sweet taste. We grew sweet potatoes in growing bags this year. It certainly wasn’t anything difficult, nor did it involve much extra work. However, the sweet potato harvest wasn’t very large. We’ve probably figured out the reason, though.

We bought the seedlings and got started

That’s right. We bought the sweet potato seedlings sometime in late April, intending to grow them in growing bags. But we’d run out of those, as we’d used them to grow potatoes. It’s worth noting that we were actually quite successful with those. That’s partly why we got some growing blocks for the sweet potato seedlings. They’re essentially blocks of growing medium encased in a standard soft plastic wrapper. It’s a thicker film that holds the growing medium together.

Photo: Radek Stepan

Transplanting and watering the usual way

We transplanted the sweet potato seedlings directly into the growing blocks themselves. It wasn’t difficult at all. We made a good-sized indentation in the block and then placed the sweet potato seedling into it. We covered everything properly and watered it. We watered the sweet potatoes quite regularly throughout their growth. The soil around them was never completely dry. Except perhaps during the hottest spells. However, sweet potatoes don’t mind the dry weather; they’re used to the strong South American sun.

Tip: A decent harvest. In August, we harvested potatoes from the bag.

Not enough space and probably too much nitrogen

The sweet potato harvest was really poor. In fact, we only harvested about three tubers: one large one and two tiny ones. It seems the situation was mainly down to the composition of the growing medium. We think there was too much nitrogen-based fertiliser in the mix. Perhaps the lack of space was also a factor. There was more space in the standard growing bags we used for the potatoes. You can, of course, see the harvest in the gallery and in the images within the text. The sweet potato chips turned out to be delicious, even though there weren’t many of them.

Sources: Author

Photo and photogallery: Radek Stepan