Sweet potato consumption has increased greatly in the past decade. This is due to improved production methods. And as a result, almost everyone can grow sweet potatoes tubers. This is possible because you can grow sweet potatoes at a very low cost.
That’s why I am teaching you how to grow sweet potatoes organically. I am using a method that my parents use every year. And the only costs they incur are for the vines and their labour. But inspite of that, they always have extra tubers.They sell these tubers to other people in the village.
Initially, I was never a farming person. Digging the dirty to plant sweet potatoes was not even on my radar. The hard labour needed for growing sweet potatoes was not for me. Some would say that I was very lazy! It wasn’t until I realised the importance of growing food that I changed. I started to cherish eating what I grew. So, I started helping in the fields willingly. Besides the tasty tubers I would eat later on, growing sweet potatoes gave my body a much needed physical activity. So, I learnt how to grow different types of sweet potatoes. I learnt most of what my parents did. And my father is a master sweet potato bed maker.
What I like about the organic method is the simplicity of using what you have. You only need compost, manure, sweet potato vines and a few garden tools. With organic growing you don’t need any chemicals and fertilisers. Instead, you can use plant waste material. You can also use animal manure to grow your sweet potatoes. So, how do you go about it?
Table of Contents
How to grow sweet potatoes organically step by step guide
Please note that, this is a method that has nothing to do with science. It’s based on personal experience and it works for me and my family. It can work for you too!
What you need to grow sweet potatoes organically
- A patch of land
- Grass, old hay, manure, tree leaves, soy stalks, maize stalks, beanstalks, old thatching grass, maize cobs or compost.
- A hoe, a shovel and maybe a rake.
- Water supply if it’s irrigation crop
- Your sweet potato vines
- Ash from firewood/ tsotso stove
These is the basics of what you need to grow sweet potatoes organically. So, let’s show you how to grow sweet potatoes organically.
The process of organically growing your sweet potatoes
Step 1: Choose your piece of land/ space
This step is very crucial for organic sweet potato growers. You must choose a piece of land with some of these characteristics.
An open space with no tree shade.
Loam to sandy soils are the best
Clay red soils will do with some adjustments.
The land must have some grass even overgrown grass is good. The more the better.
You must take note of these things
Sandy soils will need more manure and nourishment as well as water. They leach everything very quickly.
Clay soils form a compact slab on your sweet potato bed during heavy rains. This soil slab is concrete hard. Therefore if this happens your sweet potatoes won’t form any tubers. They just can’t push the soil out like loam and sandy soils. So, for clay soils, you need more grass, cobs for the bedding. This reduces the risk of your soil forming a compact slab.
I am no soil expert but I know this from personal experience.
I prefer a field which we haven’t tilled for 2 or 3 years. It contains a good lot of tufted grass. The roots of this grass contains stored nutrients. These can be utilised by your sweet potatoes. The grass and roots rot in the sweet potato bed forming composted material. This composted material is good for your sweet potatoes. It will also provide nourishment for the next crop you grow. Its not recommended to repeatedly grow sweet potatoes on the same piece of land. This will give you challenges with pests.
Step 2: Prepare your plant waste material and animal manure
This is the second step in how to grow sweet potatoes organically.
This step is important if your land is clear with little to no vegetation. This bare land have little to no nutrients because there is less organic matter. However, all is not lost. You can introduce organic matter to the soil.
Before you start digging or tilling the land, take your plant waste materials. Arrange them into a low betting that mimick your sweet potato bed. This bed should be about 30 cm wide and nothing more. It should also be about 15 cm high and not 5 cm higher than that. You can do this with any of the plant materials I mentioned above. And make as many beds from the plant material as you want to plant. You must put a distance of at least 80 cm between the beds.
If you have animal manure and compost instead of plant material, skip this process. If you have cow and goat manure, mix them with the soil as you make the sweet potato planting ridge or bed. You can also use grass beddings from broiler and chicken run. But, don’t over do it!
Be warned! Too much manure will affect the quality of your sweet potatoes. They will have poor storage properties. They may also have a bitter taste. On the other hand poor soil nutrition results in poor yields.
Step 3: Prepare your sweet potato beds/planting ridges
If you want to learn how to grow sweet potatoes organically, you have to get this right.
For a piece of land with a lot of tufted grass, the process is labour intensive. However, the yield is also rewarding.
First, you need a good, sharp hoe with a wider cutting edge. The cutting edge should be at least 15 cm wide. I usually use the biggest one around because I love physical activity. Measure where you want your sweet potato bed to go. Then start making a ridge by hoeing the grass. Shape the grass first into low bedding as I explained above with plant material. Starting with one side uproot the grass from the soil. Then arrange it upside down on the bedding area. You must make a low tufted grass bedding of at least 30 cm wide and 15 cm high. Make sure to clear grass from about 40 cm wide space on each side.
Note: Unlike with an open space, with a grass land, you are making your bedding from the grass in the field. So, as you clear the grass, you are making your sweet potato bed.
If you are using a clear open space bare land as I described in the step above, skip this process. You just go straight to digging and loosening the soil.
Digging and loosening the soil
After this, you need to start digging on the 40 cm wide spaces on each side of the bedding. Dig with a depth of at most 10 cm. Break soil lumps and loosen the soil. Also, remove any big rocks. If you don’t have plant material or grass, sprinkle small quantities of cow or goat manure on top of the loosened soil. This ensures that when you start shovelling soil onto the bedding, the manure is incorporated.
Step 4: Shape your sweet potato bed
After digging and loosening the soil on both sides of the grass bedding, start using the shovel to make the bed. You start by shovelling enough soil onto the bedding to cover the grass completely. Shovel soil from both sides and shape your bed as you see fit.
The trick
Now the trick is that the shape and size of the sweet potato bed depend on the sweet potato variety. Some sweet potato varieties produce short tubers with a roundish shape. These varieties do not need higher beds. For these types of sweet potatoes, you need wider and shorter beds.
However, there are other sweet potato varieties. I know the one that has white skin, and creamy yellowish flesh and green vines. The leaves are divided into 3 finger like projections. And the vines are bushier than the other sweet potatoes which spread like runner grass. This sweet potato variety will grow thin tubers that grow longer to the bottom of your sweet potato bed before thickening. As they thicken the tubers become sturdy, long and big. As a result, you need narrow and higher beds. We go up to 45 cm high and 20 cm wide at my rural home.
So, shape your sweet potato beds according to the variety. Your vine supplier will know which ones you need.
Step 5: Planting your sweet potato vines
So, you have managed to make your sweet potato beds. Since the process is labour intensive, I congratulate you for making it this far. By now you must already have your sweet potato vines.
First, remove any leaves from your sweet potato vines. Only leave the last one at the growing end of the vine. That one contains a new vibrant shoot so it’s better to let it grow as is. Now take clean scissors and cut your sweet potato vines into smaller pieces. Each vine piece should have at least 3 nodes but not more than 4. This is because each node is where the tubers will grow from. More nodes produce many tubers but they are smaller. One or 2 nodes underground produce a few big tubers. The quality of the tubers is also higher if there are fewer of them.
After cutting your vines use a small garden shovel to open holes for planting. You can also use a small hoe or hand; I do it by hand. When you plant only leave one node outside the soil for the leaves to grow from. Plant with your nodes facing up and cover with soil. Use your hands to press the soil around your planted vines. Do this with all your beds. I usually put one line of vines per bed. And the vines should be at least 10 cm apart but not more than 20 cm. My parents taught me that this gives bigger and high-quality tubers. But if you have a limited space you can put 2 lines or 3 on a wider bed. You just get smaller tubers but the yield is higher per unit space.
Step 6: Watering your planted sweet potato vines
After planting you should water the vines that same day. For starters a single cup of water per vine just before sundown. There is no need for watering if the soil is wet from rainfall. You can water using irrigation, drip is the best. The higher the saturation the quicker the roots develop and new shoots and leaves start forming. If you are using seasonal rainwater, plant with other crops on loam and sand soils. But for clay soil wait till a bit of the heavy rains have gone away. You don’t want heavy rain to turn your beds into concrete. Because that’s a good way not to get any tubers.
Step 7: Maintaining the sweet potato beds
For sandy soils, it’s very important to close the ends of parallel beds. They have to be closed in such a way that, runoff water gets in but not out. Trapping runoff water between beds is a good way to maintain good moisture content within your sweet potato beds.
When you start seeing new shoots and leaves it shows that the roots have started forming. When there are 3 or 4 leaves per vine add your ash from firewood on top of the beds. The ash contains some nutrients that make the sweet potatoes vines grow better. The vines become more bushy and greeny. Also, the ash helps to reduce the damage done but those tiny worms that eat sweet potato tubers. The more ash you put the better. Just don’t overdo it.
If you believe that your soil has a very low nutrient content, you can add a little bit of chicken manure. Only, if the soil has poor nutrient content. Avian manure is too strong for my liking and its more likely to affect tuber quality.
It’s also very important to keep your beds free from weeds. Weeds will compete with your sweet potatoes for nutrients. They can also provide shade which may affect the growth of your sweet potatoes. So, no weeds.
Step 8: Harvest and store: How to grow sweet potatoes orgically
When to harvest, store and eat depends on you. When your sweet potatoes have sizable tubers you will start seeing cracks on your beds. Bigger cracks means bigger tubers. You can fill these up but it’s not necessary.
When your vines start changing colour from green to yellowish and stop growing, they are almost ready. It depends on your soil type. In sandy soils, sweet potatoes lose water faster so they stop growing earlier. This means these tubers mature earlier than in soils that retain more water. This is because in soils that retain water, tubers continue growing for sometime. Some sweet potato varieties like orange-fleshed sweet potatoes are short season. They take a maximum of 2-3 months to mature. Some take longer.
My recommendation is that you wait till your soil has lost most of its moisture. I like my sweet potatoes more starchy with no moisture layer near the skin. The moisture layer near the skin will be visible after boiling. And it shows that the soil is still moist. In my village, some people wait till all the sweet potato leaves are almost gone. Then they can harvest.
Step 9: Storage
Storage of your harvest is just as important in learning how to grow sweet potatoes organically.
Sweet potatoes can go bad very quickly if not handled well after harvesting. I talked about several storage methods in:
Orange sweet potatoes: How to best encourage adoption
In my village, we use a traditional method called “pfimbi”. We dig a hole in a shaded cool area. A fire is lit inside the hole to let it dry and kill any fungi. After that, we add more ash inside the hole. We then pack our sweet potatoes inside. However, the sweet potatoes must have as little damage as possible. Storing those without harvest damage is advisable. Damaged sweet potatoes rot quickly. Also, some sweet potato varieties just don’t keep well especially the sweeter varieties. Additionally, this methods only works with dry grounds after the rain season.
You can store your sweet potatoes this way for several months. You have to check for signs of rot inside now and then. Remove the rotting ones, add more ash and put them back again. Cover the hole with a thatching grass door. Its the best for air exchange and prevents high-temperature damage. You can use plastic or metal ones but they are not ideal.
This idea works in the rural areas because we allow our animals to roam free after harvest. So, if you leave your sweet potatoes in the beds, they will be destroyed. If you have a fenced garden, you can leave your tubers in the ground and harvest as you cook. However, if left for longer, tubers lose more water. And as a result, the flesh turns into a form rubbery material!
And now you have learnt how to grow sweet potatoes organically.
Also read:
- Sweet potato health benefits
- Orange sweet potatoes: How to best encourage adoption
- Sweet potato nutrition facts
- 12 Of the best orange fleshed sweet potatoes nutrition facts
Conclusion
Whilst this process is labour intensive, it makes up for it with fewer monetary requirements. The only money you need is for the vines. But even those you can multiply them in your garden before planting. Get some from a friend during harvest time for free. Plant them in your garden water them, cut them and plant some more. By the time you want to plant, you will have a good number of vines for planting. So just like that, you have nice tubers to feed a hungry family. Do you want to learn more about growing sweet potatoes organically? Or do you have any questions about my parents’ method? Do you have any suggestions? Well, what are you waiting for? Leave a comment down below!