One of our favorite meals is a nice baked sweet potato!!! The flavor is so rich and you can’t beat them for healthy eating. I wanted to share with you how we grow sweet potatoes. They take approximately 100 to 110 days from planting to harvest so they need a long growing season. We plant ours in early May so the soil is warm and this allows for us to harvest just before frost here in our Zone 7 garden.
First it is wise to prepare the soil. We grow ours in raised beds that have been filled each winter with barn cleanings: composted manure and hay. Once that has been in the bed for about a month, we turn it in with a shovel so it is well incorporated into the soil. Anytime you grow a crop that bears underground like sweet potatoes, regular potatoes, turnips, beets, carrots, onions, peanuts, etc – you need soft, rich soil. Root crops are heavy feeders and refreshing the beds each year with composted manure is the ideal. We have grown sweet potatoes in rows right out in the main garden but we find they do SO much better in raised beds. Our beds are 5 x 10 and 10 inches deep.
Sweet potatoes are a vining plant but you can buy varieties that are “bush” types that still vine but not nearly as much. I pulled vines this year that were over 20 feet long. They are part of the morning glory family and will root at the nodes of the vines if they are allowed to touch the ground. Some folks contend that you need to keep that from happening by pruning those vines but I absolutely do not agree. Let the vines run as they will. This will act as a natural mulch and result in much healthier plants and much higher yields.
We have grown Vardemon, Georgia Jet and Beauregard types I but will say that Beauregard has proven to be the highest yielding and most healthy of the three types we have grown. It is and will be our choice for the future. The flavor is excellent!
Okay first you need plants called “slips”. You can take a sweet potato that has developed some roots and cut them apart. Put these sections in a little soil mixed with some sand in a container. Keep them warm – 70 to 80 degrees and spritz with water. Don’t let them get waterlogged or they will rot quickly. Once they begin to sprout you want to add a little more soil to. Once these plants are rooted and about 6 inches tall you can separate them and plant them into your garden beds. Most of the time I have a few left over sweet potatoes in my pantry and they have already begun sprouting by spring. It is so nice to not have to go and buy plants but if you need to usually area co-operatives and feed stores sell slips in the spring. ** I do know that some folks have success with placing the rooted slips in water in their window and letting them grow their roots this way. I haven’t done it but if it works for you that is great!
Now spacing is important because the potatoes grow underneath the plant base and sometimes they can get really big. We dug one this morning that was 8 pounds and bigger than my HEAD!!!! So you can imagine that they need room to grow. That particular potato was one of about 9 that was in the cluster of one plant. SOOOO the space needed was well over 2 feet all the way around. I recommend you planting each plant no less than 2 feet apart and make sure your rows are at least 2 to 3 feet apart. In a raised bed you are able to plant a little closer together because there is additional depth to work with and the soil is softer hopefully so the potatoes can do downward. Hope that makes sense.
You will need to make sure your area is weeded early on so that as they vines grow they are not competing with the weeds. Once the vines get going they will generally block out most weeds because of the thick mat that they create. You will not be able to get into the area to weed later. Some folks use black plastic underneath but there again you lose the rooting of the vine nodes. If you are row cropping then you could do a narrow strip of the black plastic down the row and that would allow the vines to get to soil out just past the plastic.
Sweet potatoes love hot, dry climates so they do really well when rain is at a minimum. Too much rain at the end of the season can cause molding, splitting and rot.
When the leaves begin to yellow you can start harvesting your crop. If a frost hits the plants the leaves will turn black and you need to dig your potatoes fairly quickly because they will begin to rot in the soil. I waited about a week this year and we had 2 rotten ones out of two beds, but I think a few more days and we would have had quite a few more. First I pull the vines – this allows me to get to the plants and not have to battle all those runners. Now the digging – it is so frustrating to dig in and realize that you have just split a nice big tater in two. Potato forks and fat blade shovels seem to work really well for us. You don’t want to dig in wet soil if you can avoid it. A nice, dry, sunny day is perfect. Be sure to dig away from the base of the plant to loosen the soil. The potatoes are going to be under the plant but because they can be so large you have to move in slowly. I usually go as deep as possible and then rock the shovel or fork back and forth to see if I can catch a glimpse of a potato and then gently rock them out.
When you have harvested all of them you will want to leave them out in the sun to air dry for a few hours. One of the interesting things about these potatoes is that they need to be “cured” before storing to ensure a long storage life. To cure them, they need to be spread out in a warm, humid place for a week or two. We place ours on newspaper covered tables in a large storage room. It is usually pretty warm in there but if it gets threatens to get cold we put a heater out there to keep things warm. The room doesn’t need to get below 50. I go out every day or two and turn the potatoes.
Be sure to check for rotten or damaged sweet potatoes and remove them from the bunch. A cut from digging or a bad part is not really a problem. Usually air drying during the curing process will allow the cut to heal over enough to keep it protected for a little while. These are the first to be eaten. After the curing period you can store them in a dry, cool pantry. They last a long time and are SO worth the effort.
If you want to you can process them by pressure canning very easily. I will share that information on the canning recipe page here on our site.