I flew back to Houston yesterday. One of the first things I did when I got home was to check the condition of the sweet potatoes I had planted in May. They were doing fine!
I started these plants from a sweet potato that I bought in a grocery store. I kept it on the counter for a few days, and little sprouts began to appear at one end of it. So I put it in this raised bed, and pretty soon there were baby sweet potato plants, or slips as they are called, poking up in the bed. I pulled them loose from the potato and planted them about a foot apart in the bed.
The bed was not watered all summer, and Houston is experiencing a drought; we are down ten inches for the year. The bed received no care at all. In fact, at one point it was seriously disrupted: my partner and his son dumped all the dirt out, moved the frame over about two feet and simply replaced the plants in the bed. They went on growing as if nothing had happened! Sweet potatoes are tough plants.
I poked around in the soil and found a small sweet potato, which I put in the soupe du jour for tonight, with some ramen noodles and white potatoes. I used to think that sweet potatoes and white potatoes couldn't go in the same recipe, but guess what: they can.
In Houston there's an organization called Urban Harvest that teaches people how to grow food in Houston. It's not easy to grow food here: the soil is very hard and clayey, and torrential rains alternate with long droughts and very hot weather. On the positive side, beginning in early November we have several months of cool nights, moderately warm days and gentle rains, perfect for growing greens. But summers are tough on food plants. Urban Harvest sponsors a lot of school gardens, and it advocates sweet potatoes as a sort of ground cover for the garden beds during the summer. I can see why: the sweet potatoes seem to compete well with weeds, and are happy without much water.
I used to work in the demonstration garden at Urban Harvest, and Dr. Bob Randall, the director at the time, gave me some slips of a variety that he grows in the summer as a ground cover. I planted them in my old garden in another part of Houston. They grew prolifically and even bloomed! The bloom looked a bit like a morning glory. I dug them up and was astonished to find that the underground tubers were long and slender, almost a foot and a half long by two inches in diameter. And there were a lot of them. But they were not very tasty by modern standards: they had a dry, white flesh that was not very sweet. So I didn't plant them again, but they kept cropping up in my garden for years afterwards.
Sweet potatoes are an important source of calories in much of the tropical world. Along with the Irish potato and rice, they are one of the best crops for producing a lot of calories in a small space. In the post-petroleum future, we may be eating a lot more of them, and growing more of them in our yards. In Tennessee, I plant Irish potatoes in March to harvest in July. When I have eaten all the Irish potatoes, it is time to dig the sweet potatoes. So between those two crops, I could grow all the calories I need. John Jeavons's plan for food self-sufficiency relies heavily on these two carbohydrate-rich tubers.
This particular variety in the picture here is Garnet, a variety commonly available in grocery stores but for some reason not listed by the sweet potato plant growers that I buy plants from for my larger sweet potato plantings in Tennessee. There, I grow Beauregard and Centennial, reliable varieties for Tennessee. But maybe in the spring I will try starting some Garnet plants in Houston, to take with me to Tennessee next May.