However, the hill is 25 feet by 25 feet. The planting suggestions I found on a garden website say that the plant grows between 12 to 18 inches around, so plant them 18 inches apart.
With my area, I come up with 17 rows and 17 colums roughly. That would equate to 289 plants? Seems like a lot for this area, though the math seems right.
Am I missing something about figuring area and planting requirements?