Why Are My Cucumbers Bitter?

bhofack2 / Getty Images

We love the fresh, mellow taste of a cucumber, but they can sometimes be noticeably bitter. What gives? Is it a result of improper storage or of how the cucumber was grown? And, perhaps most important, is there anything that can be done about it?

Related: Our Favorite Recipes That Use Cucumbers

It All Comes Down to Cucurbitacin

It turns out that a specific compound, cucurbitacin, is responsible for this bitter flavor. "Cucurbitacin is generally more concentrated in the skin and towards the stem end of the fruit," says Tucker Taylor, director of culinary gardens at Kendall-Jackson Wine Estate & Gardens in Sonoma County. "Lack of proper irrigation is the main reason cucumbers can be bitter, but cold weather can also be a culprit." He adds that while there are some cucumber varieties that are grown for their more bitter flavor, most modern varieties that you'll find at your local supermarket or farmers' market are sweet when grown properly.

Since cucurbitacin tends to be concentrated in the stem end of a cucumber and just under the skin, Ian Beger, resident agronomist of Castle Hot Springs in Morristown, Arizona, recommends cutting off the stem end and peeling the cucumber to eliminate most of the bitterness. "To avoid this problem entirely, plant bitter-free cucumber cultivars such as 'Sweet Slice' and 'Sweet Success,'" he says. "Watering cucumber plants once a week during hot, dry weather may also be helpful."

How Can You Tell If a Cucumber Is Bitter?

Unfortunately, there's no definitive way to tell that a cucumber is bitter just by looking at it. Taylor notes that misshapen cucumbers tend to be more bitter than normally shaped ones, and seedless cucumbers with thin skins tend to be less bitter, but the only way to know for sure is to taste it. "It's tough to tell if a cucumber is going to be bitter by its appearance," John Amann, co-chef of Castle Hot Springs, says. "Sometimes it's hit or miss in the summertime which beds in the farm will have a volunteer bitter cucumber. " For this reason, he emphasizes the importance of tasting each cucumber if you're planning on pickling it. "One bitter cucumber can throw off an entire recipe," he says.

Can You Use a Bitter Cucumber?

Yes, you can still enjoy a slightly bitter tasting cucumber. Taylor likes to make quick pickles with cucumbers that are a bit more bitter. He recommends using seasoned rice wine vinegar, which has salt and sugar to help balance the bitterness. "You can have delicious pickles in about an hour or so," he says. "Use these to top off your noodle bowls or salads, add in a stir fry, or just by themselves!" If the cucumber is just too bitter to eat, Amann recommends composting it.