The Secret to Growing Cucumbers That Never Bitter

Bitter cucumbers are the bane of every gardener’s existence, or at least the bane of every gardener who expects to bite into a crisp, fresh cucumber only to be assaulted by a bitter tang. This is a sure sign that something has gone wrong with your cucumber plant, and there might not be much you can do about it.

The two most common causes of bitterness in cucumbers are plant stress and over-maturity of the fruit. These factors, and a few other that might be beyond your control, causes a build-up of cucurbitacin compounds in the cucumbers, which taste bitter to the human tongue.

Fortunately, there are some things you can do in the spring and early summer to reduce the risk of a big bitter cucumber harvest.

Bitter Cucumber Causes & Remedies

The bitter flavor you sometimes get in cucumbers is often due to a build-up of cucurbitacin compounds that naturally occur in all members of the cucurbitacin family. The concentration of these cucurbitacin compounds can be due to factors that you can adjust to prevent a prominent bitter flavor.

Watering Stress

Inconsistent watering is one of the biggest causes of bitter cucumbers. The more watering stressthe plant experiences the more it ups cucurbitacin production, which is stored predominantly in the fruit.

Best Way to Prevent Bitterness from Watering Stress

A drip watering system is one of the best ways to prevent bitter cucumbers due to watering stress. You want to set it to the prevailing weather so that the soil is moist, without being water-logged.

The next best method is to hand water your cucumbers in the morning, and again in late afternoon. This is better than using a sprinkler as wet foliage can lead to mold, mildew and other fungal problems on the vines.

Over Maturity

The longer you let cucumbers grow on the vine the higher the natural cucurbitacin levels will be. This is a natural defense mechanism in the plant. The bitter flavor of cucurbitacin deters animals and other pests from eating the fruits, helping to protect the seeds inside. Any fruit that rots also releasescucurbitacin into the surrounding soil, which impedes the growth of other plants.

Best Way to Prevent Bitterness from Over Maturity

The best way to prevent bitter cucumbers is to pick them when they’re 6 to 8 inches long or smaller. Also with many cucumber varieties, the darker the cucumber is the more likely it is to have some degree of bitterness.

Your best bet for never getting a bitter cucumber is to only harvest small cucumbers with lighter skins that are less than 6 inches long.

Variety & Genetics

Some cucumber varieties are genetically predisposed to building up higher levels of bitter cucurbitacin in their fruits. White Wonder, Long-Green, and Landrace cucumbers, as well as most other heirloom cucumber varieties, have a reputation for being particularly bitter.

Best Cucumber Varieties to Avoid Bitterness

Your best chance for never getting a bitter cucumber is to grow one of the bitter-free varieties like Burpless, Carmen, County Fair, Diva, Fanfare, Garden Sweet, Marketmore 76, Slice More, and Sweet Slice. They’ve been specifically developed to have the lowest possible levels of cucurbitacin in their fruits.

Pro Tip

Just bear in mind that these “Bitter-Free” cucumbers are typically hybrids andwon’t produce viable seeds. This is a non-factor as long as you’re content to spend a mere $3 for a new seed packet every spring!

Cross-Pollination

On the off chance that a garden cucumber plant cross-pollinates with wild cucumber or another variety known to have high cucurbitacinlevels any cross-pollinated fruit might take on bitterness. Even worse, any seeds harvested from a bitter cucumber are likely to carry on this trait to the next generation.

How to Avoid Bitterness from Cross-Pollination

If you know there are wild members of the Cucurbitaceae family growing in your area, or you grow multiple varieties known for bitterness, it’s best not to save the seeds. Usually, the bitterness is limited to one or a handful of fruits. So, always be sure to taste-test any cucumber before selecting its seeds to be saved for next year.

Frequently Asked Questions

Will pinching off flowers help prevent bitter cucumbers?

Pinching off extra flowers can help reduce watering stress in your cucumber plant, which will reduce the risk of getting a bitter cucumber. However, this is only a significant factor if your area is suffering from a drought, or you can’t provide adequate water to your cucumbers during a long stretch of hot, dry weather.

Does poor soil cause bitter cucumbers?

If your soil is low in phosphorus and potassium it can cause plant stress and poor growth which increases the chances of bitter cucumbers. To prevent this from happening, you should test the soil where you intend to plant your cucumbers and amend it with an organic fertilizer with a modest amount of nitrogen, and a stronger percentage of phosphorus and potassium.

Ideally, it would have a modest percentage of bioavailable fertilizer the cucumber plant can take up immediately, along with time-released fertilizer to prevent bitter cucumbers later in the growing season.

Conclusion

If you never want a bitter cucumber, you need to amend your soil with a fertilizer with a strong amount of phosphorus and potassium, as well as provide the plants with a consistent watering strategy.

This will reduce the plant stress that causes a build-up of bitter cucurbitacin in the cucumbers, During times of drought or long stretches of hot, dry weather you might want to pinch off some flowers to further reduce plant stress.

Picking cucumbers when they are 6 to 8 inches or shorter also improves your chances of never biting into a bitter cucumber. Small cucumbers with lighter colored skins are less likely to have high levels of bitter cucurbitacin.