A minimum 18-inch spacing is recommended to allow the plant to fill out properly. After planting, do not cultivate around the root system or fibrous roots will be damaged. Plants should be watered when the soil begins to dry. The tubers will rot if they are overwatered. Try to water in the morning if possible so that any moisture that gets on the foliage will have time to dry before evening.
Wet foliage increases the chance of disease.
After the first fall frost, dig the tubers and remove the foliage.