How to Clean Vegetables to Remove Dirt and Pesticides, According to a Food Scientist

Chances are you’ve gotten into the habit in recent years of rinsing off your romaine lettuce or spinach. Or perhaps you don’t think twice about eating prewashed lettuce right out of the plastic container or chomping on a carrot without peeling or scrubbing it clean. Maybe you’re concerned that the head of conventional broccoli you bought still has pesticides, even though it was likely washed before it hit the store shelves. And if you’ve cooked leeks, then you know how important it is to rinse off the dirt from the inner leaves.

Whether you plan to eat celery or cauliflower, it’s crucial to first wash your veggies (in culinary school we were taught to always wash ready-to-eat food, even those prewashed salad mixes, which can harbor bacteria or debris from harvest). Cleaning vegetables is important not just to remove unpleasant dirt and pesticides but also for your health. As it turns out, if you skip cleaning your vegetables, you may be putting yourself at increased risk of a foodborne illness. 

We set out to find the right way to clean vegetables and enlisted the help of Jessica Gavin, M.S., IFT, a food scientist and blogger. She says one of the main concerns related to vegetables is the potential for harmful bacteria, like Salmonella, Listeria and E. coli, to come into contact with produce through soil or water during growth. It seems there’s a constant stream of recalls on vegetables like spinach, salad kits and even mushrooms for contamination with potentially harmful bacteria. “Contamination can also happen after harvest, during storage or preparation,” Gavin says. “Eating fresh, raw or lightly cooked produce poses a higher risk of foodborne illness, since the bacteria present aren’t always killed through cooking.”

Best Ways to Clean Vegetables

So how are we supposed to properly clean our vegetables to ensure they are safe but also still crisp and delicious? For some basics on cleaning your vegetables, Gavin suggests:

• Start by washing your hands with soap and warm water for 20 seconds before handling produce. This may sound basic, but if you handle vegetables with dirty hands, it’ll be hard to actually clean the vegetables.
• Avoid cross-contamination by using separate cutting boards for fresh, ready-to-eat produce and for raw meat. When possible, wash plastic cutting boards in the dishwasher.
• Rinse all vegetables under cold running water to help wash away bacteria, dirt or pesticides that might still linger on the veggies.
• For leafy greens, separate the large leaves and rinse them in cold water. Then, submerge them in a bowl of cold water, swishing them to dislodge any dirt. Drain and repeat as needed. Use a salad spinner to remove excess moisture or dry well with a clean kitchen towel.
• For root vegetables like carrots or potatoes, rinse them under cold running water while scrubbing away visible dirt. Wait to peel until after washing to avoid transferring any pathogens.
• Firm vegetables like cucumbers and zucchini should also be rinsed and scrubbed under cold water to remove surface contaminants, especially if eaten raw. This is also true for hard-skinned vegetables like winter squash. They should be rinsed and dried to remove surface-level bacteria.

“The goal is to avoid introducing any outside contaminants from hands, cutting boards and knives,” Gavin says. “Starting with clean tools is critical. Rinsing produce under cool, running water (around 45–55°F) keeps the vegetables’ pores closed, helping to block bacteria from entering. The running water effectively washes away dirt and bacteria.” 

What About Soaking?

Aside from sloshing leafy greens in a bowl of clean, cold water, you should avoid soaking any vegetable for a long time. Soaking vegetables can actually reintroduce any contamination, Gavin says. And avoid using any soap or commercial produce washes, as vegetables are porous and can absorb these products, potentially making you sick. “Plus, the safety and effectiveness of these washes hasn’t been thoroughly tested,” she notes.

Mushrooms, in particular, should not be soaked in water as they are quite porous and could become slimy. Gavin suggests washing them briefly under cold water, brushing off any dirt and drying well just before cutting or cooking.

If you want some extra protection against surface-level bacteria and mold, you can use diluted vinegar. You’ve likely seen trendy social media videos of berries soaking in a solution of water and a splash of white vinegar, and what follows is little bugs and debris floating to the surface after a few minutes. The same method can be used for some vegetables, as the acetic acid in vinegar can disrupt the growth of bacteria and fungi, creating an environment where they can’t thrive, Gavin explains.

“For most vegetables, a rinse under running water is enough,” she says. “But for items like cucumbers, which can harbor bacteria or mold, a quick vinegar soak can be helpful if you plan to store them. Just be sure to rinse everything well afterward to remove any vinegar taste.

Farmers’ Market vs. Grocery Store Produce

What about those funky-looking heirloom carrots or winter squash from your neighborhood farmers’ market? Surely those are safe to eat without washing first since they came right from the farm, right? Well, yes and no.

“Whether you’re buying vegetables from the farmers’ market or the supermarket, it’s important to give them a rinse before eating,” Gavin says. “Farmers’ markets and homegrown produce often travel less and usually skip some cleaning steps used for supermarket items.” 

You can often see the difference right on the surface of the vegetables. Homegrown or farmers’ market produce often has more dirt on the surface compared to veggies you buy at a big grocery store. 

“Even though store-bought produce is commercially washed, it can still carry bacteria on the surface,” says Gavin. “A quick rinse under running water helps ensure your veggies are clean and safe, no matter where they come from.”

The Bottom Line

In order to remove dirt and pesticides and reduce your risk of foodborne illness, you should clean your vegetables, even if they have been prewashed or come from the farmers’ market. Be sure to start with clean hands and a clean work area to avoid any cross-contamination. Most vegetables simply need a rinse under cool running water, but you’ll want to submerge and swish leafy greens to remove dirt and you’ll want to scrub firm vegetables, such as potatoes, carrots and cucumbers.