Cucumbers are known for being a bit bitter and for giving people gas. In this post I will look at why they are bitter, what you can do in the garden to keep them from getting bitter and then I’ll discuss a popular way to get rid of the bitter taste in the kitchen.
Why are Cucumbers Bitter?
Millions of years ago cucumbers were being eaten by all kinds of insects and so they started making a chemical called cucurbitacin, which tastes bitter to insects. This strategy worked very well and kept pests away.
Along came people who started to eat the cucumber fruit (botanically it is a fruit). It was a bitter and gave some people gas but that did not stop people from eating them. Over time humans used selective breeding to develop a new variety of cucumber known as the English cucumber, or burpless cucumber. This later types is less bitter, has fewer seeds and does not make people burp. Unfortunately, they are hard to grow in the garden and are mostly grown in greenhouses.
Cucurbitacin is actually a class of compounds, not just one chemical, and there are about a dozen of them. Only a couple,cucurbitacin B and cucurbitacin C, are found in significant amounts in cucumbers.
The plant produces these mostly in the roots, stems and leaves. Only a very small amount ends up in the fruit. Within the cucumber fruit, they are found mostly at the stem end, and right under the skin. Different cucumbers from the same plant can have different degrees of bitterness.
Grow Bitterless Cucumbers
The bitterness of cucumbers is a function of both nature and nurture. Some cultivars are less bitter and so step one is to select a variety that naturally produces less cucurbitacin. These will be labeled as bitter-free or burpless and includes these cultivars: Carmen, County Fair, Diva, Garden Sweet, Green Knight, Marketmore 76, Sweet Slice, Slice More, Sweet Success, Sweeter Yet, and Tasty Green.
Step two is to grow them so they form less bitter compounds in the fruit. The key is to keep the plant from being stressed and all of the following will help.
- Keep soil evenly moist – mulching can be very beneficial.
- Pick smaller fruit. They get bitter as they grow bigger.
- Cucumbers are heavy feeders and soil with a high organic matter level will reduce bitterness.
- Grow in full sun.
Temperature and Bitterness
Cucumbers “grow best in temperatures from 65 to 75F (18-24C) with a minimum temperature of 60F (16C) and a maximum of 90 (32C).” High fluctuations of temperature in excess of 20 °F (11C) will cause more bitterness as will growing at cool or hot temperatures.
You have limited control over temperature, but regular watering, and mulching will keep the soil cool. In cool climates they want full sun and in hot climates some afternoon shade will be better.
How Many Gardeners Have Bitter Cucumbers?
I did a quick survey in a Gardening Facebook Group and asked “How many find their home grown cucumbers taste bitter?”
77 people responded and 84% did not have bitter cucumbers.
Getting Rid of Bitterness in the Kitchen
So you grew some cucumbers and they are bitter, what can you do?
If they are very bitter you may have to compost them, but I have never had any that were that bad.
Cut the stem end off and this will remove the most bitter end. Peel the cucumber to remove more bitterness. A thick peel removes more bitterness than a thin peel. This usually does the trick.
If this is not enough you might try this trick which I found on the internet, and many people swear it works – but that does not mean much (I have my doubts and will be testing it soon).
Cut a piece off each end. Take the cut piece and rub it on the end of the cucumber in a circular motion. As you rub, you will notice that foam is produced. It is claimed that this foam is taking the bitterness out of the cucumber. Discard the ends, wash the cucumber and you are ready to eat.
Let me know in the comments if this works for you.