Proper storage is crucial for preserving potatoes and onions for long periods of time. The key factors to consider when choosing the best storage solutions for potatoes and onions include temperature, humidity, ventilation, and light exposure. The optimal storage conditions help minimize sprouting, spoilage from pests and diseases, and moisture loss. This allows potatoes and onions to remain fresh and edible for months after harvest.
Quick Overview on Storing Potatoes and Onions
Potatoes and onions prefer cool, dark, and moderately humid conditions for ideal storage. The ideal storage temperature is around 40-50°F. Temperatures below 40°F can cause potatoes to experience cold induced sweetening where they convert starch to sugar. Onions fare better in slightly warmer conditions around 32-40°F. Adequate ventilation is important to prevent rotting from excess moisture buildup. Keeping potatoes and onions in complete darkness inhibits sprouting. The optimal storage humidity level is 90-95% to prevent shriveling and moisture loss in the vegetables.
Common Storage Methods for Potatoes
Pantry Shelves or Cabinets
Storing potatoes in open-air pantry shelves or cabinets is suitable for short term storage up to 1 month. The potatoes should be kept in a cool, dark place away from light to prevent greening of the tuber skin and sprouting. Avoid storage areas that get warmer than 60°F. Inspect the potatoes frequently and remove any that are spoiled or sprouting. Place them in a basket or bowl with ventilation gaps rather than stacking in plastic bag.
Root Cellars
Root cellars provide ideal conditions for storing potatoes for 4-6 months. The underground location maintains cool temperatures around 40-50°F and high humidity levels. Make sure the cellar has adequate ventilation to prevent excess moisture buildup. Store potato varieties separately to prevent flavors from mixing. Avoid sunlight exposure by covering ventilation openings. Place potatoes in boxes, bins, or mesh bags elevated off the floor rather than directly on the dirt.
Plastic Buckets
Food grade plastic buckets with lids can create portable potato storage units. Place a 4-6 inch layer of dry sawdust, peat moss, or shredded paper in the bottom of the bucket. Add a single layer of potatoes, then another thick layer of the padding material. Repeat the layers until the bucket is full. Store the bucket in a cool, dark place like a basement or cellar. The padding material absorbs excess moisture and prevents bruising. Potatoes can last 4-6 months in a plastic bucket.
Burlap Sacks
Burlap potato sacks provide low cost, simple storage while still allowing air flow to the tubers. Fill sacks with potatoes no more than two layers deep. Tie the neck of the sack closed and hang in a cool, humid location like a basement or root cellar. The burlap breathes adequately to prevent excess moisture accumulation. Inspect the potatoes regularly and remove any going bad. With proper conditions, potatoes can store for 2-3 months in burlap sacks.
Common Storage Methods for Onions
Mesh Bags
Mesh onion bags allow ample air circulation while containing the bulbs loosely together. Hang the mesh bags in a cool area around 35°F with decent humidity. Make sure the onions are thoroughly cured and dry before placing in the bags. Check frequently for any onions sprouting or going bad. Onions can last 2-3 months or longer in mesh bags. The loose weave prevents moisture trapping while still protecting from light exposure.
Refrigerator
Storing onions in the refrigerator is a convenient option for short term storage up to 1-2 months. Place dry onions in a breathable plastic or paper bag or container. Do not wash onions before refrigerating. Keep onions towards the front top of the fridge where temperatures are coolest, between 35-40°F. Check onions frequently as refrigerators tend to have very low humidity which can accelerate shriveling.
Shelf Storage
Dry, cured onions can be stored in braids, bowls, or wire racks on shelves for 1-2 months. Keep them in cool, dry, dark conditions between 40-50°F. Make sure the storage containers allow adequate air flow and do not press on the onion bulbs. Rotate onions regularly to prevent molding and sprouting. Monitor for signs of spoilage and remove bad onions promptly to prevent spread.
Root Cellar
A root cellar or basement provides ideal long term storage conditions for onions lasting 5-6 months or longer. Maintain temperatures around 35-40°F with 60-70% humidity. Place onions in open crates, boxes, or mesh bags with ample air circulation. Keep onions away from light sources to prevent sprouting. Check onions every 2-3 weeks and remove any that are damaged or sprouting.
Key Storage Tips
Here are some key tips for getting the longest storage out of potatoes and onions:
– Cure onions and potatoes properly after harvest to maximize dormancy before storage. This means drying and allowing the outer skins to fully form on the vegetables.
– Do not wash potatoes or onions before storage. Any dirt helps provide a protective coating and washing removes the natural protective outer layers.
– Keep potatoes and onions separate, as together they will cause the other to spoil faster. Potatoes emit moisture and gases that can accelerate onion sprouting. Onions give off sulfur compounds that can make potatoes bitter.
– Maintain darkness as much as possible to prevent greening and sprouting. Use opaque containers or cover any openings that let in light.
– Check stored vegetables every 2-4 weeks and remove any that are damaged, sprouting, or rotting. Rot spreads quickly to adjacent potatoes and onions.
– Allow spaces between onions and potatoes for air flow. Do not over pack storage containers. Proper ventilation is key.
– Ideal storage humidity is 90-95%. Use moist sand, sawdust, peat moss or other wet packing materials if the storage area air is very dry.
– Do not store potatoes or onions below 40°F as cold temperatures convert their starches into sugars and affect flavor.
Selecting Storage Containers
The containers used for potato and onion storage should:
– Be opaque to block out light which stimulates sprouting
– Allow adequate air flow and ventilation to prevent excess humidity buildup
– Provide insulation to help maintain cool temperatures
– Keep stored produce elevated off direct floor or ground contact
– Be easy to access and inspect the contents regularly
Suitable materials include wood, plastic, cardboard, mesh, burlap, and more. Avoid containers that are fully airtight or watertight, as ventilation is critical. Measure the dimensions of your storage area and purchase containers that will maximize the space. Stackable plastic bins, bushel baskets, and ventilated buckets all work well for potato and onion storage.
Ideal Storage Locations
The best places to store potatoes and onions share common features that create optimal storage conditions:
– Cool temperatures between 32-50°F
– High humidity around 90-95%
– Good ventilation and air circulation
– Completely dark spaces away from light
– Insulated spaces that maintain stable conditions
Ideal storage locations:
– Root cellars or basements
– Unheated outbuildings like sheds and garages
– Underhouse crawl spaces
– Dug pits or trenches in the ground
– Refrigerators or coolers
Avoid storage areas that get too hot, dry, wet, or freeze. Fluctuating conditions can accelerate sprouting and spoilage.
Preventing Common Storage Problems
Proper storage methods and conditions help prevent issues that can lead to spoiled potatoes and onions:
– Sprouting – Keep potatoes and onions in complete darkness. Remove any sprouts as soon as they appear.
– Molding/Rotting – Maintain adequate ventilation. Discard any moldy or rotten vegetables immediately.
– Shriveling – Store in humid conditions around 90-95% humidity.
– Greening of potatoes – Do not expose potatoes to light. Store only fully mature potatoes.
– Loss of dormancy – Allow potatoes and onions to fully cure and dry after harvest before storage.
– Pests – Remove any damaged vegetables that may attract pests. Use storage containers with tight seals.
– Odors/flavors mixing – Keep onions and potatoes stored separately from each other and other produce.
– Excess moisture – Use packing materials like sawdust or peat moss to absorb moisture. Allow ventilation.
Conclusion
Storing potatoes and onions properly allows them to be preserved for months past the end of the growing season. The keys are maintaining cool temperatures, high humidity, darkness, and adequate air flow. With the right storage location and containers, potatoes and onions can last 4-6 months or longer. Monitor storage conditions closely and remove any produce that shows signs of damage or spoilage. Ideal storage extends the enjoyment of homegrown potatoes and onions while reducing food waste and costs.