Better Late than Never for Sweet Potatoes

The longevity spinach and Okinawan spinach that I wrote about last week arrived in the mail on Monday. I failed to mention in the column that I also ordered some sweet potato slips.

I’ve only grown and harvested sweet potatoes once before. It’s kind of silly of me to not plant them every year, since they are probably the most productive vegetable crop you can grow in our climate.

I know there are lots of expert sweet potato growers in Fayette County. I’m sure all of them reading this are laughing at me for getting a late start. I should have planted sweet potatoes a month ago or even earlier.

As I mentioned, I have never grown and harvested sweet potatoes before, but Janessa and I have grown the ornamental varieties in our landscape. From what I understand, most of the ornamental varieties of “sweet potato vines” are in the genus Ipomoea, which includes the sweet potatoes grown for their roots along with a number of popular ornamental plants such as morning glories and the night-blooming moonflower. Sweet potatoes are not tubers like regular potatoes. They are the actual root of the plant.

We’ve planted sweet potato vines in the middle of summer before, and they’ve done great. So when I placed my order from Baker Creek last week and noticed they had some sweet potato slips for sale, I decided to buy a few.

If you are familiar with Baker Creek Seed Co. (rareseeds. com), you will know that the slips I ordered are no ordinary orange-fleshed sweet potatoes, like the ones you buy at the grocery store. The ones I ordered are some fairly exotic purple varieties. One is called “Myanmar Purple” and the other is “Lilac Beauty.” Both of these are considered Asian varieties, which possess low to medium sweetness. The purple color indicates that they are full of antioxidants.

According to Baker Creek, Lilac Beauty forms roots with a purple flesh. Myanmar Purple forms roots with magenta skin and cream-colored flesh with streaks of pink.

I ordered a total of 15 slips, which are young sweet potato plants that were grown from a tuber. Like regular potatoes, sweet potatoes will grow sprouts under the right conditions. Unlike regular potatoes, though, these sprouts that grow from sweet potato eyes include some root hairs that will grow into a new plant. These are sprouts are known as “slips.”

I planted them this Tuesday in a bed that gets full sun. First, I used a spading fork to loosen the soil. Then I liberally sprinkled some Microlife 6-2-4 All Purpose Organic Fertilizer into the bed. How much? About a handful for each plant. Most organic fertilizers, including Microlife’s products, will not burn plants like synthetic chemical fertilizers such as Triple 13. If you over-fertilize with organic fertilizer, you are usually just wasting money, not harming the soil or your plants.

Next I dug holes for the slips. I spaced them about two feet apart. I didn’t plant them in rows, but rather in a big block. The vines will spread and grow quite wildly. If you plant in rows, most experts recommend a row spacing of three feet. Some people grow the vines up trellis to manage the growth of the vines. The vines themselves are quite attractive for landscaping purposes. Think of them as a ground cover that loves full sun.

Like I said, I’m no expert at growing sweet potatoes. I’m taking a lot of advice from Howard Garrett, a.k.a. The Dirt Doctor, who is one of Texas’ foremost organic gardening experts. In his book “Texas Organic Vegetable Gardening,” Garrett notes that sweet potato vines will readily wilt in hot weather. However, he says this is not necessarily a sign that the plant needs water. He advises to maintain even moisture to avoid cracked and misshapen roots. He says mulching aids greatly in maintaining even moisture.

The book’s entry on sweet potatoes includes another interesting note: “Sweet potato vines have been used to smother nutgrass.”

Now that’s something that might interest a lot of gardeners in this area.