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You are here: Home arrow Articles arrow Grow your own arrow Growing Sweet Potatoes


Growing Sweet Potatoes

Written by Leonie

Growing sweet potatoes is becoming more popular in the UK now that we have been experiencing warmer summers and there are varieties of sweet potato available that are better suited to our shorter summers. I have grown sweet potatoes successfully for two years, this will be my third year growing them and I'd like to share my experiences with those who wish to grow this vegetable.

The variety of sweet potato that I grow (T65) has been bred and selected for our shorter summers, the flesh of the tuber is more creamy in colour than the orange colour of tubers bought in supermarkets, and has a nicer flavour in my opinion.

Sweet potatoes are grown from shoots or "slips". Slips are produced by submerging part of a tuber into a glass or jar of water. Use matchsticks to suspend the tuber if necessary. I start my sweet potatoes off in this way around the end of January to mid-February leaving them in a bright and warm place.

After a few weeks the tubers will start to produce slips and fine white roots will begin to grow below water level. Keep the jars topped up with water so that they don't dry out. When the slips are about 4" or 10cm long gently twist them off the tuber and place in a jar of water. There will be no roots attached to the slips at this stage. After a few days in water the slips will produce their own set of roots. When they have a healthy set of roots pot them individually into a small pot filled with potting soil. Leave the tubers in their jars of water, as you twist off the slips more will be produced.

Keep the potted on slips safe from frost and still in a warm place. Once they are showing signs of continuing growth start to harden them off gradually as the last frost date for your area starts approaching. Sweet potato plants will not tolerate frost at all so keep them well protected.

Prepare the ground where you plan to grow your sweet potatoes. It is recommended to grow them under black plastic for added warmth but this is something I have never done. Find the warmest and sunniest position you have. They can be grown vertically up a wigwam or trellis but I allow mine to trail along the ground. Sweet potatoes like similar conditions to potatoes, well drained soil with a little manure mixed in and they will need moisture to swell the tubers. Try to avoid fluctuating moisture levels otherwise you may get tubers that have a rough surface or they may have a tendency to crack. I plant my sweet potato plants approximately 40cm apart in two stages: A few go in just before the last frost dates for our area, but they are covered with cloches to protect them. And the remaining plants go in after the last frost dates for our area. Last year there was very little difference in size and quantity produced between the two plantings.

Keep them well watered and weed free during the summer months. They may take a while to get going but they will soon find their roots and start trailing quite quickly. You can pick some of the young shoots and use for greens. I haven't tried this yet so can't comment on what they taste like.

Leave the sweet potato plants in the ground for as long as you possibly can, they need approximately 110 days between planting out and lifting. Most of the bulking up in tuber size is done in the last few weeks so having just a couple more weeks in the ground will make a difference. Lift them just before the first frosts are expected. When you lift them be very gentle as the skins are delicate and will bruise easily. Also be careful you don't put the fork through the tubers when lifting them.

Leave the tubers in a warm humid place (airing cupboard) for a couple of days or in the warmest room of the house for up to a week so that their skins can cure. Then store them in a dry and cool place ideally around 10C. Remember to reserve a few tubers for producing slips next year.

There are few pests and diseases to watch out for in the UK. Last year some of my sweet potato tubers were damaged by wire worm but there was no slug damage. In crop rotation plans you should avoid planting sweet potatoes following from root crops. For companion planting marigolds are considered a good companion and carrots, beetroot and potato are considered bad companions.

There are many ways to cook sweet potatoes but my favorite is to bake them wrapped in foil, when ready add a knob of butter and freshly ground pepper. Sweet potatoes are an excellent source of carbohydrate and have a low glycaemic index. Foods with a low glycaemic index cause a slow and steady rise in blood sugar levels which is preferrable to high glycaemic index foods that cause a rapid rise in blood sugars often leading to cravings and overeating. Low glycaemic index foods are particularly suitable for diabetics. Sweet potatoes are rich in vitamin C and E which are antioxidants that help to fight heart disease and some cancers.

Article produced by Leonie. Not to be reproduced without prior permission.