Extension

Whether you like them baked, roasted or topped with marshmallows and cinnamon, sweet potatoes are a popular addition to many gardens.

 

Despite record-breaking rainfall this month, gardeners are still digging in and getting gardens planted. It’s a good time of year to plant a favorite warm-season crop – sweet potatoes.

 

Sweet potatoes need to be planted when the soil is at least 60 degrees Fahrenheit at a depth of 2 inches for sufficient warmth. While many gardeners are used to incorporating more organic matter into the soil, this isn’t necessary for sweet potatoes. They perform best in sandy loam soil; however, if the drainage is good, they can tolerate other soils. The soil pH should be between 5.5 and 6.5 and gardeners should work in about one-half pound per 35 feet row of fertilizer such as 10-20-20 before planting.

 

While some plants are grown from seeds, sweet potatoes are grown from slips, which are sprouts produced from mature sweet potatoes. These are available at local garden centers. When shopping for slips, look for those that are 8-10 inches long with at least five leaves and a good root system. Slips should also have stocky stems.

 

When planting, keep in mind that sweet potatoes grow well in raised beds. If gardeners have heavy soil, the beds should be about 10-12 inches high. For sandy soil, 8 inches will be fine. If raised beds aren’t available, gardeners can use a tiller or shovel to form ridges that are about 3 feet apart and 10 inches wide. Plant the slips about 12 inches apart with at least three nodes below ground.

 

Oklahoma gardeners know how brutally hot the summer can be. Fortunately, once established, sweet potatoes are fairly drought tolerant. Watering every few days to keep the soil moist is sufficient. Keep in mind that the vines will naturally wilt in the heat of the afternoon sun, but this wilting doesn’t necessarily indicate that they need water. Watch to see if the vines revive by early evening. If they don’t, go ahead and water. 

 

After about four weeks, the sweet potatoes can be side dressed with the same amount of fertilizer that was used before planting.