The 5 Worst Foods to Buy From the Produce Section at Costco

Love you, Costco, but I'm skipping these for now.

Costco’s the ultimate playground for those looking to save money by purchasing big, bulk buys. We are always stumbling upon intriguing or unusual items you won’t typically find in a generic grocery store. There are significant savings with buying large quantities of food and beverages, as well as home goods, which is why it’s super cost-effective to leave Costco with a packed car, loaded with everything from cleaning products and toiletries to bottled beverages and canned goods.

When it comes to food, especially produce, it’s important to consider quantity, savings, and how often you realistically consume or cook with a product before recklessly tossing it in your cart. If you can’t consume everything in time due to shelf-life, you’re more susceptible to food spoilage and monetary waste (which sort of defeats the whole purpose of shopping at Costco, right?).

“Buying in bulk can be cost-effective, especially for larger households or those who consume a lot of fresh produce,” says registered dietitian Trista Best, MPH, RD, LD. “Costco offers a diverse selection of fruits, vegetables, and herbs, often including organic options, and its large quantities can be convenient for meal planning or stocking up on commonly used items,” Best explains.

Certain types of produce are better than others, especially if you’re shopping for yourself or a smaller household. Inspection is key—you might get lucky with some beautiful fresh berries the day you’re shopping, in which case, you should grab them fast and check out. Yet, for the most part, these are the worst picks to buy at Costco.

Berries

Delicate berries, such as raspberries, blackberries, blueberries, or strawberries, are not only highly perishable but also sensitive to handling. “Their soft texture makes them prone to bruising or crushing, which can accelerate spoilage, so it's important to carefully inspect each berry and handle them gently to minimize damage and maximize their shelf life,” Best suggests. It’s okay to open the container and move them around to check for mold—berries are more prone to be contaminated due to mold, pests, and insects, Best notes.

And, don’t wash right away. Wash and store berries when you’re ready to eat them or they’ll spoil faster. “Do not wash berries until you are ready to use them, as berries are prone to mold growth when exposed to moisture,” Best explains. “Store berries in a breathable container instead of airtight containers or ziplock bags, and store the container of berries in the refrigerator's crisper drawer or a dedicated shelf to keep them cool,” Best suggests. They’ll stay fresher longer. You can also freeze them and enjoy them within eight to 12 months. “Rinse the berries gently and remove any stems or leaves, pat dry to minimize excess moisture, and spread them out in a single layer on a baking sheet to put in the freezer,” Best says. Once firm, add to freezer bags or containers. Best’s tip? Freeze berries individually to prevent them from clumping together.

Leafy Greens

Buying large packages of leafy greens, such as spinach, lettuce, and kale, can be great for those who use them often, in smoothies, as a base for salads or protein bowls, or in omelets. “However, it's crucial to have a plan for consumption due to their shorter shelf life,” Best says. If greens are a weekly staple, it may be worth it—just be sure to store properly in breathable bags to extend shelf-life and use in time. And, when shopping at Costco, be mindful of packages that contain excess moisture. “If buying packaged produce, check for signs of damage or moisture that may indicate poor handling or storage practices,” Best says. If they’re close to spoiling, freeze them.

Frozen leafy greens last for eight to 12 months. “Blanch the greens by briefly immersing them in boiling water, followed by an ice bath to halt the cooking process, and then drain and pat dry before freezing,” Best says. Portion out into freezer-safe bags or containers. “Another option is to blend the greens into a puree and freeze them in ice cube trays for convenient individual portions,” Best suggests. Throw a cube in the blender for a single-serve smoothie, for example.

Exotic Fruits

Exotic fruits, or rather fruits that aren’t typically found in local or regional areas, include dragon fruit, rambutan, passion fruit, persimmons, lychee, jackfruit, starfruit, guava, papaya, and pomegranate—to name a few. And, while they’re most definitely intriguing, you might want to hold off on buying them unless they’re nice and ripe during peak seasons or you’ve had them before and know you like them (especially when buying exotic fruits in bulk).

“While Costco may offer enticing exotic fruits, it's important to assess the quality and price before purchasing, as exotic fruits can sometimes be expensive and may not always meet expectations in terms of taste or freshness,” Best says. “Consider trying smaller quantities initially to evaluate quality and determine if they align with your preferences,” Best suggests.

Melons

Juicy watermelon and cantaloupe during peak season and summer are great, as long as they don’t go bad. “Costco's oversized produce offerings, like large melons, may provide great value for larger households or those who regularly consume them, but for individuals or small households, it's essential to consider whether quantity can realistically be consumed before spoilage,” Best says. Proper storage and planning help mitigate waste. Store watermelon, cantaloupe, and honeydew at room temperature. “Once ripe, move them to the refrigerator, which helps slow down the ripening process and extends shelf life,” Best notes. “If you have cut melon, cover the exposed flesh with plastic wrap or transfer it to an airtight container before refrigerating, as it’ll help prevent melon from drying out or absorbing unwanted odors from other foods,” Best recommends.

Slice and freeze if you buy large quantities of ripe melon. “Cut into chunks or cubes, remove the rind and seeds, lay the melon pieces on a baking sheet in a single layer, and place in the freezer until firm,” Best says. Once firm and frozen, transfer the melon to a freezer-safe bag or container for use in smoothies, fruit salads, and snacks. Frozen melon lasts about four to six months. Or, blend into a purée and freeze in popsicle molds for a refreshing, sweet treat, Best says.

Onions

Sure, you can leave Costco with one onion for the week, but Costco sells onions in bulk, and at a killer price point, which might tempt you to take the deal and stock up. If you cook with onions a lot or have a large family, it might be smart, but in most cases, it’s not. Plus, storage is tricky, as onions interact with many common staples when in close proximity and are more likely to spoil.

Onions must be stored in a cool, dark, and dry place that’s well-ventilated and away from direct sunlight, such as in a pantry, root cellar, or cool basement, Best notes. When storing, keep them away from certain foods. “Onions release gasses that can cause other produce to spoil faster,” Best explains, so for instance, to prevent premature spoilage, keep onions and potatoes apart, as potatoes release moisture and gasses that can make onions sprout and spoil faster.

Chop and store in an airtight container or resealable bag and place in the refrigerator to save time during meal prep. “If you have an abundance of onions, consider preserving them by pickling, caramelizing, or making onion jam,” Best says, as onions taste great in condiments for a flavor enhancer. Or, freeze them and use them within six to eight months. Best says, “Peel and chop onions according to size preference, spread in a single layer on a baking sheet, and place in the freezer until pieces are firm.” Add to freezer bags or containers, removing as much air as possible to minimize freezer burn. Or, slice or dice and freeze in an ice cube tray with a little water or oil.

Tips For Buying Fresh Produce from Costco

As a rule of thumb, only buy produce in bulk if the savings are worth it and you’re guaranteed to eat it all in time. For instance, Best says, “Apples are a common fruit that can be enjoyed in various ways and have a relatively long shelf life, so when purchased in bulk, such as a 10-pound (4.5 kg) bag, you can typically save around 10% to 20%, [over] individual apples.” (A 10-pound bag ranges from $8 to $12, depending on variety and season.)

Carrots are another great example, as they’re versatile vegetables to use during the week. “Buying a 10-pound (4.5 kg) bag of carrots in bulk can save you around 15% to 25% compared to purchasing them by the pound,” Best says. (Typically, a 10-pound bag ranges from $5 to $8.) Best also suggests avoiding produce that’s out of season, so you wouldn’t want to buy Brussels sprouts or butternut squash during summer, as their peak ripeness is in cooler weather.

Storage is also essential, so keep breathable bags on hand. “A breathable bag, also known as a produce storage bag, is designed to allow air circulation while still providing some protection for the stored items,” Best explains. “These bags typically have perforations or mesh-like material that enables airflow, which reduces moisture buildup and prevents produce from becoming damp or soggy,” Best says. They’re an alternative to airtight bags, such as Ziploc.

It’s also a good idea to buy produce in season and inspect it thoroughly. “Produce that’s more likely to be overly ripe in-store include bananas, avocados, and stone fruits (plums, peaches, etc.), whereas produce prone to being under-ripe includes pears, mango, and pineapple,” Best says. As for inspecting, Best recommends looking for fresh, vibrant colors and avoiding items with bruises, mold, or any other signs of decay.

Assess the firmness and texture of fruits and vegetables—they shouldn’t be too soft or have mushy spots, Best notes. For instance, melons and pineapples should have a pleasant aroma, Best explains, and produce shouldn’t ever have an off-putting or unpleasant smell. And, the produce most susceptible to pests, mold, and insects are berries, leafy greens, potatoes, grapes, and tomatoes. So, be on the lookout at Costco with those foods, especially, before tossing them in your cart.