Q: I am growing cucumbers which have turned out bitter. Can I add something to the soil to make them sweeter?
A: This is a fairly uncommon occurrence on newer hybrid varieties. However, many of us have been experimenting with older, heirloom species which has resulted in me getting this question twice this week.
Bitterness is due to the formation of two specific terpenoid compounds which are found in cucurbit plants. Cucurbit plants include squash, cucumbers, some melons, pumpkins and gourds. The terpenoid compounds can be found in seedlings, roots, stems, leaves, and fruit. There are two genes which control bitterness in cucumber; a dominant one produces extremely bitter fruit and a recessive one sometimes found in the leafy portion of the plant and in the fruit (fleshy part of the plant).
It is rare for bitterness to manifest itself but when it does the bitter taste will be more heavily located in the stem end of the fruit or just below the rind or peel. Weather (cool temperatures) and environmental (shady sites) conditions may trigger the bitter taste to show up in vegetables grown in our home gardens. Nothing can be added to the soil to change the taste of cucumbers once they start to mature. Bitter taste may also occur if the cucumbers are left on the vine too long or if they are stored with other very ripe fruit and vegetables.
What is the final answer? Peel the skin off the cucumber and cut off the ends, if it still tastes bitter to you then toss it in the compost bin. Be sure the plant is receiving adequate irrigation, sufficient sunlight, and pick the cucumber when it is smaller rather than larger. Consider adding in some hybrid cucumber varieties to your garden so you will have a smaller chance for bitterness to be displayed.