Sweet potatoes are rich in Vitamin A and are a low GI carbohydrate source. But best of all: growing sweet potato is easy.

They do not need very fertile soil, they are quite drought resistant and they crowd out weeds. They are fairly resistant to pests and diseases, although one must take care to use virus free vines.

The flesh of sweet potatoes can vary from cream to deep orange, while the skins can be red, purple, maroon or copper coloured.

Soil requirements for growing sweet potato

Well-drained, moderately deep sandy soil is ideal for sweet potatoes, although they can grow in a wide variety of soils. Broadcast four large handfuls of matured compost or manure per plot size of 1m x 1m (1m2). Incorporate it into the soil before planting. If your soil is clayey, work in extra compost.

The plants are sensitive to water logging, salinity and alkalinity, so the optimal pH is 5.5 – 6.5. In areas of high summer rainfall substantial ridges should be made with two rows of plants in each. The plants are grown on ridges, which should be 25 – 30 cm high and 20 – 30 cm wide. Generally the ridges should be about 1m apart.

Planting sweet potato

The home gardeners can propagate vine cuttings from some sweet potatoes bought at the greengrocer. Plant them quite close together and cover with 5 cms of soil. This can be done from July onwards, but in heavy frost areas it is best to ridge the soil or even cover them in plastic. Watering should increase when the shoots become visible.

When sprouts are 25 – 30 cm long, break them off and use for planting. Approximately 21 cuttings are needed for a plot of 2.5 m x 2.5 m with 3 rows of sweet potato if the rows are 0.8 m apart. Place the sprouts 30 cms apart. Each sprout is planted by covering it for at least half its length with moist soil. They must be firmed in well. Planting can take place from October to December and they can be harvested after four to five months, depending on the cultivar. It is also suggested that the planting be done at two week intervals, to extend the harvesting period.

growing sweet potato
We can also eat the young leaves of the sweet potato plant.

Water well in the first few weeks and as a general guide sweet potato requires between 450 and 600 mm of water well distributed throughout the growing season of 5 months. Apply a top dressing of LAN three weeks after planting and again at five to six weeks after planting. Close off soil cracks regularly to prevent the sweet potato weevil. Also be on the lookout for leaf mottle and leaf spot. Remove infected plants.

Harvesting sweet potato

Harvesting with a fork and the soil should be soft during harvest to prevent breakage and skin damage. Do not water for about 30 days before harvesting as a way of curing. You can harvest all of the roots or only what you want at a time. Store sweet potatoes in a cool dry place. Guard against storage diseases such as soft rot, surface rot and dry rot, due to fungi.

growing sweet potato
Sweet potato skins can be red, purple, maroon or copper coloured.

What can we do with sweet potatoes?

Most of us think only in terms of eating the storage roots (which is what you buy in the supermarket) as a form of carbohydrate. You can use them in baking breads, rolls and scones and to make jam, relish and even juice. We can eat tips of shoots and young leaves as a vegetable, while smallholders give crop residues to livestock.

To read other articles about growing vegetables and crops click here.


Leave a Reply

Your email address will not be published. Required fields are marked *