There is much to say about sweet potatoes as they are a great addition to an edible garden. They are easy to grow, and can become almost unstoppable in Perth gardens!
There is a saying in permaculture circles that the “Answer is always Sweet Potato” because it is such a useful plant for many reasons.
Sweet Potato Plant Details
Sweet potatoes are a vine species and their scientific name is Ipomoea batatas, which is in the morning glory family (Convolvulaceae).
Sweet potato plants will root into the soil at leaf nodes and quickly cover an area.
While it produces an edible tuber like the potato, the sweet potato is actually a swollen root as opposed to the potato which is a swollen underground stem.
Sweet potatoes are perennial in climates that remain warm year-round, but they can serve as a highly productive annual in cooler areas.
They benefit from rich soils, but will hold their own in gutless sand or even heavy clay. They will grow in full sun to part shade and even tolerate very shady areas quite well.
The only thing they really don’t tolerate is cold temperatures, when the soil drops below 10 degrees, but even then they can be grown in polytunnels successfully.
How to Grow and Harvest Sweet Potatoes
Sweet potatoes grow easily from ‘slips’, a cutting of 10-15cm in length taken from the end of the vine.
You can usually obtain cuttings from other gardeners in the community, especially in autumn when the plant is often so vigorous it needs regular pruning to keep it in check.
The cuttings are placed in a jar filled with water in a sunny position to encourage some root growth or simply placed in pre-prepared rich soil.
Another method is place the sprouted section grown from an old sweet potato (a slip) which is removed from the sweet potato and placed in water to develop roots and then transplanted.
Transplant slips into well composted and friable garden soil. The sweet potato tuber can be harvested between 3 and 6 months.
Tubers are best harvested when about 20cm long. Tubers will become woody the longer they are left in the soil. Unharvested tubers can grow very large and be a several kilograms in weight.
Do not wash tubers after harvesting and remove the dirt with a dry brush. This prevents them from rotting due to too much moisture. Wrapping them in paper can protect them from fungus or insects.
Store sweet potatoes in a cool, dry place for up to 5 months.
Sweet potato slips are often available from our abundance basket and keep well in water for several days
Why Grow Sweet Potato?
The obvious reason to plant sweet potato might be for the delicious tubers, but in fact the leaves and stems are also edible. Try them in salads and they shine in stir fries cooked with garlic.
They multiply easily by simply putting a new slip in the soil, and are both drought and flood tolerant, making them a functional edible ground cover.
A living ground cover is so important in our hot climate to help shade roots of other plants growing nearby. It will also make a great trellising plant. Their hardiness to grow in a range of soil conditions make them a great tool to loosen compacted soil and add organic matter to soils.
Sweet Potatoes are a great option for a fire break as they also hold moisture.
Sweet potatoes grow well as part of a Banana Tree Guild.
As well as being a useful ground cover, they don’t compete with nutrients from the very hungry banana.
They also help reduce root competition from other competitive plants like lemongrass or vetiver, which are also useful plants in the guild but ones you don’t want to take over.
How to Store Sweet Potatoes
When cured correctly (about a week or two in a hot, humid place) sweet potato can last for months in storage. The curing process covers over nicks and cuts, protecting the sweet potatoes from spoilage.
Dehydrated sweet potato chips taste amazing and also store well.
Nutritional Value of Sweet Potatoes
A superbly versatile vegetable, they provide more nutrition than their plain potato cousins, while having the added benefit of being lower in starch.
They are packed with beta-carotene, more than just about any other veggie, including carrots. They are also a solid source of vitamin C and dietary fibre.
Mineral-wise, sweet potatoes are good providers of manganese, crucial for healthy bones and absorbing calcium, and potassium.
Their nutrient profile promotes a healthy heart, good digestion, a strong immune system, and enduring eyesight.
Sweet potato chips make a delicious meal or healthy snack
In addition to the common orange flesh variety, there are a range of colourful types of sweet potato, including yellow, white and purple.
Did you know?
The sweet potato is actually more closely related to tomatoes and capsicums than potatoes.
What are your tips for growing Sweet Potato?
We would love to know your tips for growing a great crop of sweet potatoes.
Which varieties do you grow? How do you enjoy cooking and eating them?
Please let us know in the comments below or tag us in your social posts #urbanrevolution.