Why are Cucumbers Bitter?

Cucumbers are a popular vegetable consumed worldwide. They have a mild, refreshing taste and crunchy texture that make them a staple ingredient in many salads, sandwiches, and side dishes. However, sometimes cucumbers can develop a bitter taste, which can be quite unpleasant and render the vegetable unpalatable. There are several potential reasons why cucumbers may become bitter.

Factors Contributing to Bitter Cucumbers


Certain cucumber cultivars are more prone to developing bitterness than others. Bitterness is connected to the presence of cucurbitacins, which are steroidal compounds that impart an undesirable flavor. Some common bitter cucumber varieties include Marketmore, National Pickling, and Calypso hybrids. On the other hand, cucumber types like Sweet Slice, Double Yield, and Straight Eight tend to have better flavor consistently. When purchasing cucumber seeds or seedlings, it helps to select designated “burpless” or non-bitter varieties.

Growing Conditions

Environmental growing conditions play a big role in whether or not cucumbers will become bitter. Factors like temperature, irrigation, and soil composition can impact taste.

Temperature – Cucumbers thrive in warm weather with daytime temperatures around 75-85°F. However, excessively hot weather above 90°F can trigger increased bitterness. Cool temperatures below 60°F can also cause cucumbers to become bitter. Maintaining optimal temperatures will help cucumbers grow smoothly and avoid flavor issues.

Watering – Inconsistent watering leads to fluctuations in moisture levels, which cucumbers do not tolerate well. Too little water causes drought stress, while overwatering increases bitterness. Using drip irrigation and maintaining even soil moisture is best. Allowing cucumber soil to completely dry out between waterings should be avoided.

Soil – Cucumbers prefer nutrient-rich, well-draining soil with a pH between 6.0-6.8. Poor drainage or overly compacted soil restricts root development, contributing to bitter cucumbers. Insufficient nitrogen levels in the soil can also cause bitterness. Gardeners need to prepare soil properly and fertilize appropriately for ideal cucumber growth.

Maturation & Seeds

As cucumbers mature on the vine, bitterness increases naturally near the seeds. Overripe cucumbers left too long before harvesting tend to become very bitter and seeded. It’s best to pick cucumbers young and early, when they are 6-8 inches long for slicers and 4 inches for pickling types. The small, immature cucumbers will be mildest. Reducing seed production via pruning or using all-female hybrids also lowers bitterness.

Stress Exposure

Any experiences that shock or stress cucumber plants can quickly increase bitterness. Common stressors include herbicide injury, sudden weather changes, insect/disease damage, and physical handling of the plant. Trying to limit cucumber stress is key to preventing bitter flavors. Providing a healthy, protected environment and avoiding over-manipulation of the vines helps keep bitterness at bay.

Storage & Processing

After harvest, bitterness can develop if cucumbers are stored at high temperatures or left to sit for too long. Refrigeration is necessary to keep cucumbers fresh and flavorful. However, chilling injury can occur if cucumbers drop below 50°F. For processing pickles, a proper brining method is needed to prevent bitterness. Caution should be used when fermenting, as the lactic acid can bring out bitterness. Proper post-harvest handling preserves pleasing cucumber taste.

How to Reduce Bitterness

Luckily, gardeners are not powerless against bitter cucumbers. Several tips can help control or avoid bitterness in homegrown cukes:

Start with Non-Bitter Varieties

Seeking out cucumber cultivars described as cool weather, burpless, bitter-free, or sweet tasting stacks the deck in your flavor. Reliable options include DMR 401, Diva, Fanfare Hybrid, Sweet Success, and Bush Crop. There are even “mini” cucumber types bred to be bite-size with non-bitter attributes.

Test Soil & Adjust as Needed

Before planting, test garden soil and amend as required to create the ideal growing medium for cucumbers. They need pH between 6.0-6.8, plenty of nitrogen, and good drainage. enhance sandy soils with compost and avoid over-compacting clay soils. Addressing soil issues proactively prevents many potential bitterness triggers.

Use Row Covers

Row covers allow airflow and rain penetration but protect young cucumber plants from insect pests, cold snaps, and extreme heat. Keeping plants comfortable under row covers while roots establish helps prevent environmental stress. Just be sure to remove the covers once flowers appear to allow pollination.

Water Consistently

Applying 1-2 inches of water weekly with drip irrigation gives cucumber roots a constant moisture supply. Watering early in the day allows the foliage to dry out, preventing disease. Drastic moisture fluctuations will shock the plant, so avoiding droughts and waterlogged soil is key.


In addition to preparing soil, supplement cucumber plants with a nitrogen-rich fertilizer every 2-3 weeks. Fish emulsion, blood meal, and compost tea provide nutrients during the growing season. Just don’t overdo the nitrogen, as excess can make plants focus on foliage over fruit.

Monitor for Pests

Scout plants to watch for signs of pests like cucumber beetles and squash bugs. These insects can spread diseases and damage plants. Set out sticky traps, remove bugs by hand, or use insecticidal soap if infestations occur. Preventing major pest damage helps avoid bitterness issues.

Harvest Timely

Don’t leave cucumbers on the vine to become oversized, misshapen, and seedy. Use pruning shears to cut cucumbers at the proper small, tender stage. Timely harvesting ensures flavorful cucumbers and encourages more production.

Handle with Care

When picking, move carefully to avoid damaging vines. Gently place harvested cucumbers into a container, rather than tossing them in. Bruising from rough handling causes bitterness. Take same care not to injure fruits when washing and storing them.

Chill Promptly

Never leave fresh cucumbers out on the counter for extended periods. Quick refrigeration stops metabolic processes that lead to bitterness. Storing cucumbers around 45°F with high humidity keeps them crunchy and flavorful longer.

Common Questions about Bitter Cucumbers

Why do my cucumbers taste bitter?

Bitterness in cucumbers is caused by cucurbitacins, compounds that impart an undesirable flavor. Many factors can trigger increased cucurbitacin levels, including cultivar, growing conditions, plant stress, and harvesting methods. Choosing the right variety, providing ideal soil and weather, and timely harvest/storage help prevent bitterness.

How can you get rid of bitterness in cucumbers?

If bitterness develops, it can sometimes be remedied by peeling the outer skin and slicing off the ends containing the seeds. Soaking in ice water for at least an hour may help draw some bitterness out. Salt water brine baths are another potential remedy. But it’s very difficult to rescue an already-bitter cucumber, so prevention is key.

Should you eat bitter cucumbers?

Most bitter cucumbers are still safe to eat, but the unpleasant taste makes them rather unpalatable. Bitterness usually develops around the stem end and seeds, so taste-testing sliced rounds can help identify if only part of the cucumber is affected. Consume moderately bitter cucumbers with caution and avoid eating extremely bitter ones.

How do you fix bitter pickles?

For bitter pickling cucumbers, try soaking in ice water for a few hours, changing the water periodically. An hour-long soak in salt water can also help draw out bitterness. Adding grape leaves to the jar may be beneficial, as they contain tannins that reduce bitterness naturally. But preventing bitterness through proper growing and pickling methods is ideal.

Why are my cucumber pickles bitter?

Pickles can become bitter if the cucumbers weren’t harvested at a small enough size or if the brining solution wasn’t strong enough. Leaving cucumbers out too long before brining allows bitterness to develop. Use unwaxed pickling cucumbers, chill quickly, and properly prepare brine using canning salt and vinegar for the best pickle flavor.

Can companion planting reduce cucumber bitterness?

Yes, some plants make great companions that can improve cucumber growth and flavor. Planting cucumbers with basil, beans, beets, celery, lettuce, onions, radish, and tomatoes can have positive effects. Companions provide beneficial shade, nutrients, trellis support, and insect protection to lower plant stress.


When cucumbers become bitter, it negatively impacts the taste and reduces their usability in recipes. By understanding the common causes of bitterness and how to prevent it, gardeners can successfully grow non-bitter, flavorful cukes. Start with tolerant varieties, provide optimal soil and growing conditions, harvest on time, handle gently, and refrigerate quickly for the best results. With careful planning and attentive care, bitter cucumbers can be avoided in the home garden. The reward will be enjoying the mildly sweet, refreshing flavor that makes cucumbers an essential vegetable.