There’s nothing more disappointing than pulling out a sweet potato, only to discover mushy, soft spots that ruin the taste and texture.
These spots are more than just a nuisance – they’re a signal that something went wrong along the way, whether in storage, handling, or growing conditions.
Understanding the causes of these soft spots and knowing how to prevent them can help ensure a healthier, more enjoyable sweet potato harvest next season.
Let’s dig into what those mushy spots mean and how to keep your sweet potatoes fresh and firm!
First of All, Understanding What Causes Soft Spots
Soft spots in sweet potatoes can be a result of several factors, but they’re typically due to rot.
When sweet potatoes experience excess moisture, physical damage, or improper storage, they become susceptible to fungal or bacterial infections that cause these mushy spots.
Left unchecked, this rot spreads quickly, making the potato inedible.
1. Moisture Problems: Too Much of a Good Thing
Sweet potatoes are susceptible to rot if they’re exposed to too much moisture, especially after harvest. High humidity or dampness encourages bacterial growth and fungal infections that result in mushy spots.
If they’re stored in a humid or poorly ventilated environment, they’re at a greater risk of becoming soft and unusable.
Tip: Store your sweet potatoes in a dry, well-ventilated area with moderate temperatures, ideally between 55-60°F (13-15°C). Avoid storing them in the refrigerator, which can damage their cell structure and make them more susceptible to moisture-related rot.
2. Physical Damage: Handle with Care
Sweet potatoes are sensitive to bruising and cuts, which provide an open door for bacteria and fungi.
Even a small nick in the skin can lead to a mushy spot if it becomes infected.
This damage can occur during harvesting, handling, or transportation, especially if the potatoes are tossed around or placed under heavy objects.
Solution: When harvesting or handling your sweet potatoes, be gentle! Use a garden fork to lift them from the soil, and avoid dropping or stacking them heavily. Inspect each potato for signs of cuts or bruises and use any slightly damaged ones first to prevent rot from spreading in storage.
3. Improper Curing: The Secret to Longer Storage
Curing sweet potatoes after harvest helps toughen their skins and allows minor cuts to heal, reducing the risk of rot.
During curing, the potatoes are exposed to a warm, humid environment (around 80°F and 85-90% humidity) for 5 to 10 days, which seals the skins and prepares them for longer storage.
Without curing, sweet potatoes remain vulnerable to fungal and bacterial infections that can cause soft spots.
How to cure: After harvest, place sweet potatoes in a warm, humid spot for about a week. If you don’t have a controlled space, you can try a corner in a heated room or a warm, covered area with a small water container to increase humidity.
4. Improper Storage Conditions
Even after curing, sweet potatoes need proper storage to stay firm and fresh.
Storing them at too low or too high a temperature or in areas with high humidity can result in rapid softening and spoilage.
Refrigerators, for instance, are too cold and will cause sweet potatoes to become soft and tasteless.
Ideal storage tips: Keep sweet potatoes in a cool, dark, and dry place, like a pantry or cellar, and avoid any location that gets too hot or cold. Don’t wash them before storing, as excess moisture can encourage rot.
5. Choosing Healthy Sweet Potatoes for Storage
If you’re selecting sweet potatoes to store, start with healthy, unblemished ones. Any potato with small nicks, bruises, or signs of rot should be eaten first or separated from the others.
Healthy, intact sweet potatoes will last longer and are less likely to develop soft spots over time.
Pro tip: Check stored sweet potatoes every few weeks, removing any with signs of rot to keep the others fresh.
Final Thoughts
While soft spots in sweet potatoes can be frustrating, they’re preventable with the right steps. By understanding what causes these mushy areas – whether it’s too much moisture, improper handling, or lack of curing – you can ensure your sweet potatoes stay fresh, firm, and ready to enjoy.
Following these simple tips for harvesting, curing, and storing your sweet potatoes will help keep rot at bay and give you a bountiful harvest that lasts.
Next time you harvest, remember these tips, and your sweet potatoes will thank you! Happy gardening!
