Growing sweet potatoes can be immensely rewarding when done right. But it does require some planning and forethought to get the best harvest possible. One key consideration is what to plant alongside your sweet potatoes. The right companion plants can greatly enhance growth, flavor, and yields, while the wrong ones can stunt plants or attract pests.
Below we’ll explore some of the very best options for companion planting with sweet potatoes. We’ll also look at plants you’ll want to keep far away from your sweet potato patch. Follow these companion planting tips and tricks for thriving, super productive sweet potato vines.
Why Companion Planting Matters
Companion planting provides a number of important benefits for gardeners, including:
- Natural pest control – Specific plants help repel or deter insect pests, reducing the need for chemical pesticides. Others attract beneficial predatory insects that keep pests in check.
- Enhanced crop growth – The right companions provide nutrients, shade, trellises, or other supports that improve growth and yields.
- Better flavor – Aromatic herbs, onions, garlic, and other companions can infuse more complex flavors into produce.
- Soil health – Planting a diversity of plants with different root structures, depths, and nutrient needs keeps soil healthier long-term.
- Efficient use of space – Combining plants with different growth habits and maturation rates maximizes production in the same garden space.
Best Companion Plant Picks for Sweet Potatoes
Here are some of the very best options to consider when looking for plant pairings that can benefit your sweet potato vines and tubers:
As legumes, all types of beans help fix nitrogen in the soil through their roots. This makes nitrogen more available for sweet potato plants. Bush bean varieties like Contender or Provider are great choices that don’t compete for space as much as vining beans. Or try taller pole bean types by providing a trellis for them to climb.
Keep bean plantings close to (but not directly on top of) your developing sweet potatoes to foster sharing of soil nutrients.
Radishes mature very quickly, helping to break up and aerate soil early in the growing season. Their fast developing roots also help suppress weeds before sweet potato vines start spreading out.
Once radishes are harvested, the space is opened up for the sweet potato plants to expand into. Daikon and Champion radish varieties work particularly well.
Marigolds are one of the most versatile and easy-to-grow companion plants. Their bright flowers deter a whole host of common garden pests like beetles, aphids, whiteflies, and nematodes. Planting marigolds liberally around the perimeter of sweet potatoes acts as a “living insecticide.”
For maximum effect against pests, go for marigold varieties like Lemon Gem, Tangerine Gem, or Orange Boy.
Nasturtiums provide a double benefit as a companion plant. Their edible flowers and leaves add a delightful peppery flavor and vivid color to salads, while their trailing vines help suppress weeds and cover bare soil.
But they also repel multiple insect pests including aphids, squash bugs, beetles, and whiteflies. Tuck nasturtiums around the edges of your sweet potatoes or interplant them throughout.
Garlic & Onions
Onions and garlic plants help mask the scent of your sweet potatoes, making it harder for pests like beetles to find them. Their strong odor also deters deer and rabbits from grazing.
As alliums, they may also deter damaging nematodes in the soil. For easy growing, go with onion sets or break apart a garlic bulb into individual cloves for planting.
The bright, daisy-like flowers of cosmos add beauty while also bringing in a diversity of pollinators. Attracting more bees, butterflies, and other pollinating insects benefits the whole garden ecosystem.
Certain cosmos varieties release chemical compounds from their roots that suppress nematode worms and other soil-dwelling pests.
Mint makes a great filler companion for empty spots in your sweet potato rows or beds. Its quick growth helps crowd out weeds.Mint releases oils that deter aphids, flea beetles, cabbage looper caterpillars, and other insects.
Just be sure to plant mint in containers buried in the soil unless you want it taking over your whole garden!
The colorful waves of petunias don’t just provide a beautiful backdrop for sweet potatoes – they also repel a spectrum of pests like asparagus beetles, leafhoppers, tomato worms, aphids, and more.
Certain varieties like Wave spreaders even bloom longer, producing pest-deterring flowers for months. Go for mixes of colors for maximum impact.
Plants to Avoid Around Sweet Potatoes
On the flip side, there are certain plants that should never be grown near sweet potatoes, as they will hinder growth and yields:
Yam Family Crops
Avoid planting sweet potatoes near other yam family crops like true yams, ginger, turmeric, or ornamental sweet potato vines. These close botanical relatives easily share diseases and pests.
Rotating planting sites for all yam family crops is critical to prevent disease carry over in the soil.
Sunflowers & Corn
While sunflowers and corn thrive in the same warm conditions as sweet potatoes, they should be kept separate. As tall, sprawling plants, they will compete for sunlight, nutrients, and space.
Their extensive root systems rapidly deplete soil moisture and nutrients needed by sweet potatoes. Give them their own separate garden area.
Cabbage Family Crops
Members of the brassica family like cabbage, kale, cauliflower, and broccoli do not make good companions for sweet potato plants.
Substances emitted from brassica roots have an inhibitory effect on the growth of sweet potatoes. Avoid planting them together in the same season or even closely following one after the other.
Melons & Squash
Prolific vining plants like melons and squash will quickly take over garden space needed for sweet potato vines to spread out. Their dense foliage will block precious sunlight as well.
Unless you have abundant space, keep melon and squash plantings clearly segregated from sweet potato beds.
Irish or russet potatoes should not be grown near sweet potatoes. They share too many of the same pest and disease vulnerabilities. This includes potato beetles, blights, nematodes, and more.
If they must be grown in the same garden space, separate them as widely as possible and rotate planting spots annually.
Growing Tips for Healthy, Productive Sweet Potatoes
To get the very most out of your sweet potato patch, follow these key tips in conjunction with companion planting:
- Rich soil – Sweet potatoes thrive in loamy, well-draining soil enriched with plenty of compost or rotted manure before planting.
- Sunny spot – Pick a spot that gets full sun for at least 8-10 hours daily for highest yields.
- Warm soil – Wait until soil has warmed to at least 65°F before transplanting slips or starts.
- Spacing – Space plants 12-15 inches apart in rows, with 36-48 inches between rows. Expand spacing for vining varieties.
- Rotation – Avoid planting sweet potatoes in the same spot as close relatives like tomatoes or peppers.
- Mulching – Use straw, leaves, pine needles or other organic mulch to retain moisture and reduce weeds.
- Watering – Supply 1-2 inches of water per week. Avoid letting soil completely dry out or become waterlogged.
- Nutrition – Side dress with a balanced organic fertilizer or compost tea a few weeks after transplanting.
- Curing – Cure freshly dug sweet potatoes for 7-10 days in 80-85°F heat to improve texture and sweetness.
Troubleshooting Common Sweet Potato Problems
Even whencompanion planting, issues can still pop up. Here are some answers to frequently asked questions:
Why Are My Sweet Potato Leaves Drooping or Wilting?
If sweet potato leaves start shriveling up or collapsing, the plants are extremely thirsty. Their shallow, fibrous roots easily dry out between waterings. Make sure soil moisture extends 6-8 inches down. Supply a deep soaking of 1-2 inches of water per week for best growth. Avoid water stress during crucial tuber bulking.
What Causes Holes in Sweet Potato Leaves?
Holes chewed in sweet potato foliage are typically caused by insect pests like flea beetles, Colorado potato beetles, caterpillars, leaf-footed plant bugs, or cucumber beetles. Keep plants as healthy and vigorous as possible. Remove pests by hand picking or spray with approved organic insecticidal soap if infestations persist. Companion planting with marigolds, nasturtiums or onions helps repel chewing insects.
Why Are My Sweet Potato Tubers Cracking Open?
Lengthwise cracks in developing sweet potatoes are often caused by irregular soil moisture. Too much water after a dry period leads to rapid growth that the tubers cannot accommodate, causing cracking. Maintain consistent, even soil moisture by checking soil frequently and watering when the top few inches become dry. Cracking is usually just a cosmetic issue – cracked sweet potatoes are still fine to eat if the inside looks healthy.
What Causes Misshapen, Lumpy Sweet Potatoes?
Poorly shaped, deformed sweet potatoes with lumps or constrictions are typically caused by inadequate nutrition in the soil. Sweet potatoes need a steady supply of nutrients like nitrogen, phosphorus and potassium for proper development underground.
Add plenty of rich compost or well-rotted manure before planting. Side dress growing plants with a balanced organic fertilizer or compost tea every 4-6 weeks for a strong and even shape.
How Can I Tell if My Sweet Potatoes Have Spoiled?
Signs that a sweet potato has spoiled include discolored, mushy or moldy flesh, often with a foul, fermented odor. Wrinkled, withered skin can also signal spoilage. Storage problems like excess humidity, too warm temperatures, or ethylene gas exposure hasten deterioration. Discard any roots that appear damaged, rotten or diseased. Cure and store cured sweet potatoes properly to maximize freshness.
Companion Planting for a Winning Sweet Potato Harvest
By leveraging the benefits of strategic companion planting, you can maximize the growth, flavor, and productivity of sweet potato vines in your garden. Certain plant pairings enhance the soil, deter pests, and improve crop results. Just steer clear of unsuitable companions that can impede growth.
What companion plants have you found most beneficial for growing great sweet potatoes? Let us know in the comments below! We’d love to hear what plant combinations have worked well in your garden.