Sweet potatoes one of the only two edible and non toxic plants in the morning glory family (the other one is water spinach). They are grown for their starchy root bulbs; the leaves and young shoots of some sweet potatoes are also used as a vegetable. They are not closely related to potatoes.
Sweet potatoes grow as a vine with winding stems, they have heart shaped or palmate alternate leaves. The starchy bulbs are up to 40 cm long and tapered, they come in various colours from white, creamy to orange and purple.
How to grow:
Plant sweet potatoes in a sandy, light, well drained soil, add well matured manure. Choose a sunny spot, sweet potatoes love heat, temperatures of about 24 °C are optimal, so plant them out in late Spring. Sweet potatoes can be grown using the root bulbs. Put a bulb in water or plant it into soil and shoots will grow from the eyes. If the shoots are 15 cm long, remove all but the leaves at the very tip. Cover the shoots with soil, just leave the tip out of the ground, the shoots will develop roots at every leaf knot. Plant the shoots 40 cm apart.
Keep the cuttings moist but avoid water logging them, mulch very well. The plant develops a lot of leaves and long vines and will cover the ground quickly. Build a small trellis to drape the vines over to offer some more space and to avoid the vines from rooting.
The established plants don’t need much watering and little fertilising. Avoid high nitrogen fertiliser, it will only encourage leaf growth.
Constantly harvest young shoots and leaves.
Harvest bulbs after 4 to 5 months.
Pests and other problems and how we deal with them:
Sweet potatoes are very easy to grow. Crop rotation avoids accumulation of root nematodes that could become a problem. Fungal diseases can be treated with milk spray or Eco fungicide.
Warm season crop, start in early Spring and plant out late Spring.
Propagate using the shoots.
How to harvest and use:
Constantly harvest young shoots and leaves by cutting 30 to 40 cm (the tender part) off. Use them for stir fries or as you would use spinach.
When the leaves die down, dig out the roots. Clean them and let them dry in the sun for a few days. They can be stored in a cool dry space for several months.
The roots are very versatile. They can be roasted, mashed, cooked or fried. Add them to casseroles, curries and stir fries or cook a soup out of them. They are also good in sweet dishes like sweet potato pie.
They go very well with walnuts and pecans, butter, sour cream and feta cheese. Spices like nutmeg, cinnamon, allspice and cumin go very well with sweet potatoes.