Sweet Potato
Ipomoea Batatas
Sweet potatoes, or Ipomoea batatas, are a versatile and nutritious crop known for their sweet flavor and vibrant color. Originating from Central and South America, they are a staple food in many cultures and are celebrated for their health benefits. Growing sweet potatoes can be rewarding, providing both beautiful foliage and delicious tubers.
Everything it needs
9 essentials at a glance
Watering
Sweet potatoes prefer consistently moist soil but do not tolerate waterlogged conditions.
Water deeply once a week, allowing the top inch of soil to dry out between waterings. In hotter months, you may need to increase frequency to twice a week. Signs of over-watering include yellowing leaves and root rot, while under-watering may cause wilting and stunted growth.
Light
Sweet potatoes thrive in full sun, requiring at least 6-8 hours of direct sunlight daily.
Ideal placement includes a south-facing garden bed or a sunny patio. They can tolerate partial shade but may produce fewer tubers in less light.
Soil
Sweet potatoes prefer well-draining, sandy loam soil with a pH range of 5.8 to 6.2.
Ensure good drainage to prevent root rot, and consider using a potting mix designed for vegetables that includes compost and perlite for aeration.
Humidity
Sweet potatoes prefer moderate humidity levels of around 50-70%.
To increase humidity, mist the leaves or place a humidifier nearby. Signs of low humidity include leaf curling and browning edges.
Temperature
Sweet potatoes thrive in warm temperatures, ideally between 70-85°F (21-29°C).
They are sensitive to frost and should be grown in USDA hardiness zones 9-11. Protect them from cold temperatures by covering them or bringing potted plants indoors during chilly nights.
Fertilizing
Use a balanced fertilizer with an NPK ratio of 10-10-10 or 5-10-10.
Fertilize every 4-6 weeks during the growing season, starting when the plants are about 6 inches tall. Signs of nutrient deficiency include yellowing leaves (nitrogen), poor growth (phosphorus), and stunted tuber development (potassium).
Pruning
Prune sweet potato vines to control their spread and encourage bushier growth.
Use clean, sharp scissors to trim back excessive growth in early summer. Deadheading is not necessary, but removing any dead or yellowing leaves can improve air circulation.
Repotting
Repot sweet potatoes when they outgrow their current container, typically every 1-2 years.
Signs that repotting is needed include roots growing out of the drainage holes and stunted growth. Choose a pot that is 2-4 inches larger in diameter and follow these steps: gently remove the plant from its pot, loosen any tightly bound roots, and place it in fresh potting mix.
Propagation
Sweet potatoes can be propagated through slips, which are shoots that grow from the tubers.
To create slips, place a sweet potato in water or moist soil, and once sprouts appear (usually in 2-4 weeks), cut them off and plant them in soil. The best time to propagate is in late spring when temperatures are warm.
When it's unhappy
Yellow leaves
Why it happens
This can be caused by over-watering or nutrient deficiency.
How to fix it
Check soil moisture and adjust watering accordingly. Fertilize if nutrient deficiency is suspected.
Root rot
Why it happens
Root rot is typically caused by overly wet soil conditions.
How to fix it
Ensure proper drainage and reduce watering frequency. Remove affected roots and replant in fresh, well-draining soil.
Wilting
Why it happens
Wilting can occur due to under-watering or high temperatures.
How to fix it
Increase watering frequency and ensure the plant is not exposed to extreme heat without adequate moisture.
Pest infestations (e.g., aphids, beetles)
Why it happens
Pests can attack sweet potato plants, especially in warm weather.
How to fix it
Inspect plants regularly, and treat infestations with insecticidal soap or neem oil as needed.
Poor tuber development
Why it happens
This can be due to inadequate sunlight or nutrient deficiencies.
How to fix it
Ensure the plant receives full sun and consider fertilizing with a balanced fertilizer to promote healthy growth.
Care through the year
Spring
In spring, plant sweet potato slips after the last frost. Ensure the soil is warm and well-prepared with compost. Water regularly as the plants establish.
Summer
During summer, maintain consistent moisture and monitor for pests. Fertilize every 4-6 weeks to support growth, and prune back excessive vine growth if necessary.
Fall
In fall, prepare for harvest by checking the tubers for size. Begin harvesting when the leaves yellow, and protect plants from early frost.
Winter
In winter, if grown in containers, move sweet potatoes indoors to a warm, bright location. If grown in the ground, mulch to protect the soil and tubers from freezing temperatures.
Toxicity & Safety
Sweet potatoes are generally non-toxic to pets and children. However, the leaves and stems can cause mild gastrointestinal upset if ingested in large quantities. Symptoms may include vomiting or diarrhea.
Good to know
How often should I water my sweet potato plants?
Water sweet potato plants deeply once a week, allowing the top inch of soil to dry out between waterings. In hotter months, you may need to water more frequently.
Why are my sweet potato leaves turning yellow?
Yellow leaves can indicate over-watering or a nutrient deficiency. Check the soil moisture and consider fertilizing if needed.
What is the best way to propagate sweet potatoes?
The best way to propagate sweet potatoes is by creating slips from the tubers. Place a sweet potato in water or moist soil, and once sprouts appear, cut and plant them.
When is the best time to harvest sweet potatoes?
Harvest sweet potatoes in late summer to early fall, typically 90-120 days after planting, when the leaves begin to yellow and die back.
Can sweet potatoes be grown in containers?
Yes, sweet potatoes can be grown in containers. Choose a large pot with good drainage and use a well-draining potting mix.
What pests should I watch for on sweet potato plants?
Watch for aphids, beetles, and root-knot nematodes. Regular inspections and treatments can help manage these pests.
How do I store harvested sweet potatoes?
Store harvested sweet potatoes in a cool, dark place with good ventilation. Avoid refrigeration, as it can affect their flavor and texture.
Grows well with
Track this plant in your garden.
Set care reminders, log growth, and join a community of plant lovers.