Sweet Potatoes

Why you absolutely have to grow sweet potatoes!

Growing Sweet Potatoes is very easy in tropical and sub tropical climates. (And not difficult in cool climates, either.)

In fact, the question is not how to grow sweet potatoes, it's rather how to stop sweet potato vines from taking over the whole garden! Sweet potatoes are vigorous growing vines and will take over if you let them!

Sweet potato is one of the most useful food plants in a warm climate:

      Sweet potatoes are the perfect substitutefor normal potatoes.

      Sweet potatoes have less disease problems.

      Growing sweet potato vines is much easierthan growing other potatoes.                    Sweet potatoes are very nutritious.                                                 

And sweet potatoes grow with little water and fertilizer.

      You can use sweet potatoes in the kitchen just like you would use potatoes. Boil them, steam them, mash them, fry them... But sweet potatoes have more uses:

        Young sweet potato shoots and leaves are yummy in stir fries and salads.

        Sweet potatoes also make a wonderful quick growing ground cover.                         You can use them as a living mulch and to keep weeds down.

So, how do you grow sweet potatoes?

How To Grow Sweet Potatoes

Sweet potato plants are fast growing vines that cover the ground. Originally they come from Central and South America, which means they area warm weather vegetable. You need a long warm season to grow good sweet potatoes.

There are sweet potato varieties with red, yellow and white tubers. The red ones have the highest vitamin A content, and have become the most popular variety. But all sweet potatoes are very nutritious in general, especially if you use the leaves and shoots, too. It would be hard to find a plant that produces more nutrition per square foot than the humble sweet potato!

Propagating Sweet Potatoes By Making "Slips"

The quickest and easiest way to grow sweet potatoes is to use cuttings or slips. Simply cut a piece of a runner, at least 6 inches long.

Remove all the leaves except for the tiny leaves at the very tip. Plant the cutting by covering the whole length with soil, only the leaves of the tip should stick out of the ground.

The cuttings will root at every leave node. Not just the leave nodes under the ground will root. A sweet potato also grows roots from every leave node that develops as your cutting grows.

Place them on the ground or in a bin, cover them with soil, and keep them moist. The tubers will develop shoots, called slips. Slips can be snipped or pulled off and planted out when they are about 6 -8 inches  in size. The original root will continue to produce more slips.

Planting Sweet Potatoes

Sweet potatoes like growing in sandy soils, lots of sun, lots of space, and a reasonable amount of water and nutrients. They love heat. The hotter it is the faster they grow. While the best soil for sweet potatoes is sandy,  they can grow in all soils. If you have heavy soil plant sweet potatoes on mounds or ridges.

Sweet potatoes don't like heavy, waterlogged soils, cold weather, and fertilizers high in nitrogen (like chicken manure, it makes them grow lots of leaves but no potatoes). Raising the beds improves the drainage (very important) and gives the tubers a nice deep soil to develop in. (Otherwise you may end up with small, bent and forked sweet potatoes.)

The soil should have a good supply of nutrients, for example from digging in mature compost. Do not use fresh manures or any fertilizers high in nitrogen (like pelleted chicken manure). You'd just end up with plants and roots and no tubers (sweet potatoes).

Growing sweet potatoes requires some space, so plant them where they can spread. Space your cuttings or slips about a foot apart in a row, and leave three to four feet between rows. (If you plant in rows, that is...)

Mulch thickly between plants and even between the beds to intially keep the weeds down. Once the sweet potatoes grow they will choke all weeds down themselves.

For planting time the general recommendation is to plant a patch in late spring in our climate. Sweet potatoes do need four to six months of reasonably warm weather to mature.

How much water? How much plant food?

Although sweet potatoes are a very tropical vegetable they can get by with little water once established. However, the freshly planted cuttings need to be watered regularly.

Make sure plants don't become waterlogged. If your soil isn't free draining it's safest to grow sweet potatoes on mounds.

If you think the quality of your soil is not good enough fertilize your plants at planting time, at six weeks of age, and maybe once more at twelve weeks. Or whenever you remember to do it...

Just make sure you use a balanced fertilizer, for example seaweed extract. A sprinkle of sulfate of potash also doesn't go astray. Compost that had lots of wood ash in it is even better. Avoid high nitrogen fertilizers. Root crops like potassium and phosphorus, not nitrogen.

Harvesting sweet potatoes

After four to six months, depending on the temperatures, your sweet potatoes will be ready. You will see that the original stem of your cutting or slip will have thickened, and when you carefully lift the plant with a fork you should find two or three sweet potatoes at the base. You can harvest sweet potato leaves and young shoots at any time, it does not affect the plant or tubers.