Sweet Potato Companion Plants – Good and Bad Companions
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Companion planting is working with nature. It is a natural way to encourage healthy plant growth, ward of pests and diseases, improve flavor, and maximize space in your garden at the same time. Today we’re looking at sweet potato companion plants.
Which plants grow well with sweet potatoes, and which ones don’t?
About the Sweet Potato
The sweet potato, or ipomoea batatas, is a tuberous root vegetable belonging to the Morning Glory family, Convolvulaceae, genus Ipomoea. It is a starchy vegetable with a sweet taste that is eaten in warm places throughout the world.
Sweet potatoes are commonly assumed to be related to other types of potatoes in the Solanum tuberosum family, part of the Nightshades. However, they are actually related to the Morning Glory family in the Ipomoea family.
In some areas of the world, the sweet potato is also known by the name yam, but this is a misnomer as the yam is a completely separate tuber in the Dioscoreaceae (yam) family, genus Dioscorea.
In this article, we will be talking about the sweet potato, Ipomoea batatas, and sweet potato companion plants.
Growing the Sweet Potato
The sweet potato is a staple crop native to Central and South America. It made its journey to Polynesia via the Hawaiian Islands almost 500 years before Christopher Columbus landed in the Americas.
Since it is a tropical crop, sweet potatoes grow well in warm weather and prefer rich warm soil. Too much nitrogen can cause lush, leafy vines but a poor crop in the form of small and stunted tubers.
Sweet potatoes will grow in poor soils, but if grown in heavy clay soils or sandy soils they might become deformed or stringy.
Sweet Potato Propagation
Even though the sweet potato is not related to actual potatoes in the Nightshade family, it is usually classed with them for growing and companion planting purposes.
The main difference in starting these two plants is that while potatoes are started from the eye of a seed potato, sweet potatoes are started from a slip or a small plant with roots. Both plants, though, share similar pests in the form of diseases and bugs, and also benefit from similar companion plants.
I’ve used sweet potato slips to cover my permaculture coconut circle. Wherever the sweet potato vine touches the ground, it produces roots. You can simply dig up these roots (which often have a small sweet potato attached) and re-plant it elsewhere.
Sweet potatoes are a great cover crop. They grow incredibly fast when they’re happy!
Good Sweet Potato Companion Plants
Companion planting is a good way to help ward off diseases and pests. It’s a natural way to avoid using harmful chemicals.
Benefits of companion planting include:
- Encourage healthy plant growth
- Ward off diseases and pests
- Improve and increase the flavor of the edible parts of the plant
- Maximize garden space
This last benefit comes in handy whether you have a large garden or a small one, as it allows you to grow more food for your family or make some space for flowers to liven up your house.
Just as there are certain plants that make great companion plants and will provide all these benefits, there are certain plants that make poor neighbors. If planted next to each other, they can have the opposite effect on each other – none of the benefits you would otherwise get from good companions.
Let’s take a look at some good companion plants for sweet potatoes, as well as some plants to avoid putting with sweet potatoes.
Even though they are not related, potatoes and sweet potatoes can be companion planted with some of the same plants and get the same benefits.
Herb Companion Plants for Sweet Potatoes
Starting with the herbs, some herbs that are beneficial companion plants for sweet potatoes are:
- Summer savory (Eden Brothers Seeds – free shipping over $79)
- Oregano (Eden Brothers)
- Dill (Eden Brothers)
- Thyme (Eden Brothers)
Each of these herbs is good at deterring certain pests such as flea beetles, aphids, spider mites, and sweet potato weevil.
Oregano is also a good ground cover for sweet potatoes as they grow, and can also be mulch for them as well.
Vegetable Companion Plants for Sweet Potatoes
Some good vegetables to grow with sweet potatoes are beans such as pole beans and bush beans.
- Pole Beans (Eden Brothers)
- Bush Beans (Eden Brothers)
These plants are good for sweet potatoes because they fix nitrogen in the soil. These companion plants will replace any nitrogen the sweet potatoes remove from the soil as they grow and mature.
Many root vegetables are good companion plants for sweet potatoes. These include:
Flowering Companion Plants for Sweet Potato
Some good flowers to companion plant with sweet potatoes are:
- Marigold. Marigolds repel nematodes, which are pests that get into the roots of plants and destroy them. Marigold seeds at Eden Brothers.
- Nasturtium. Nasturtium repels pests such as the Colorado Potato Beetle.
- Sweet Alyssum. Sweet alyssum attracts pollinators such as wasps.
Bad Companion Plants for Sweet Potatoes
Now that we’ve looked at some good companion plants for sweet potatoes, let’s look at some plants that definitely do not make good companion plants for sweet potatoes.
The main plant that should not be planted with sweet potatoes is squash.
Here are plants that should NOT be companion planted with sweet potatoes:
- Squash. Squash is a bad companion for sweet potatoes and regular potatoes because they compete for space and will not grow to their full potential.
- The same goes for any other plant that grows low to the ground, such as gourds and pumpkins. These will inhibit each other’s growth and compete for space.
- Another plant that should not be planted with potatoes that will also cause problems with sweet potatoes is the tomato. Tomatoes and potatoes planted near each other increase the chances of both plants contracting diseases that harm both plants.
- Sunflowers. Sunflowers, when planted near potatoes, increase the chance of potatoes contracting a fatal disease called potato blight. This is the same disease that affected potatoes and caused the Irish famine of the 1840s.
Sweet potatoes are a great addition to any garden and are a good, dense source of nutrients to add to your diet.
Since they are native to Central and South America, they prefer warm weather and good soils, although they can be grown in cooler environments if they are started inside.
Even though they are not related to potatoes, sweet potatoes can be grown with some of the same companion plants since they are prone to some of the same diseases. Companion planting can help ward off pests and diseases, as well as help plants make more flavorful fruits and grow more lushly.
On the other hand, bad companions can cause atrophy and poor growth as well as possibly attract more diseases and pests to plants. Companion planting also helps create more space in your garden.
Companion planting is a great way of growing with nature! Are you adapting companion growing principles in your garden? Let us know!
I’m confused about where to plant nasturtiums. Some articles I read say to put them right in the garden bed near the plants. Others say to plant them away from the garden bed to draw the bad insects away from the garden. Which way is best?
Hi Margaret! What a fantastic question. I used to wonder the same thing. So, nasturtiums attract some pests while they repel others. For example, slugs, aphids, and caterpillars love nasturtiums. But these flowers do repel potato beetles. So, it’s a great idea to plant nasturtiums alongside potatoes and sweet potatoes. But, if you plant them next to other pants that, say, slugs like, such as cabbage and squash, you might end up with a big slug-fest in your garden.
It’s all about companion planting and making sure all your plants make great neighbors! I hope that helps you out with your garden plans, and have a wonderful day!
Great article, thanks! We are planning out our new garden now and just wondering how near is near when it comes to tomatoes and potatoes/kumara? Is a couple of metres enough space between the beds?
Hey there Dulcina!
Potatoes and sweet potatoes are quite different when it comes to companion planting with tomatoes. Potatoes suffer from the same disease called Blight, as tomatoes. Sweet potatoes and “regular” potatoes will happily grow together – if your weather is suitable, that is. I’m not sure what climate you’re in, but if you’re in a warm climate, sweet potatoes may thrive where potatoes really will not.
The main issue with sweet potato is that it loves to spread, and spread big! It needs a lot of space. Most likely, you’ll find that a couple of metres isn’t enough – the sweet potato plant will easily cover that distance. And, even though you can control their spread, they sprout new sweet potatoes wherever the vine touches the ground, so I prefer to let them have as much space as they need – more sweet potatoes!
When you grow tomatoes and potatoes together, I recommend having them as far apart as possible. Blight can spread incredibly quickly via wind and rain. It can also stay dormant in dead plant matter or your soil for years! Rotation cropping helps a lot in preventing blight spread, as does destroying any affected plant matter.
The herbs mentioned in the article will help control any transfer of wind-transmitted disease, but a couple of metres is most likely not going to cut it. That said, if you haven’t had issues with blight, you can probably get away with this for a year, but this make sure you rotate your crops next year so you don’t grow potatoes and tomatoes in that same spot for another few years after.
This form of “bad” companion planting is different from other companions, where they, for example, fight over the same nutrients. In that case, a couple of metres is fine, especially if you plant some nitrogen fixers etc. in between.
Hope that helps and let us know what you’ll decide!