Why do some cucumbers Taste bitter?- Gardeners Guide

A freshly picked cucumber is always a delight in the plate. It is full of water and nutrients. Certainly, it is healthy plus very easy to grow. All this makes cucumber an ideal choice for vegetable and hobby gardeners. But what will happen if you spend months in caring your cucumber plant and after harvesting, you find Its bitter!

It is the biggest nightmare for any gardener. I am sure most of you may have harvested bitter cucumbers in the past. I certainly did many times. It is not good to eat and more importantly demotivate you from gardening.

If you know and feel the frustration of wasted time and effort for few bitter tasting cucumbers then you are not the only one. Every new gardener faces this and no one wants the bitter one. So how to stop cucumbers from getting bitter? Is there any easy solution? Yes, there is but before that lets first understand the causes of bitter cucumbers.

Why do some cucumbers Taste bitter
Why do some cucumbers Taste bitter?

Read my Previous Article: Why Garden Plants Leaves turn Yellow? How to FIX it?

What makes a cucumber taste bitter?

Cucumber belongs to the Cuccurbits or Cucurbitaceae family. Some other members of this family include all Gourds, pumpkin, marrows, courgettes, squash, and especially the Bitter gourd. They get their name due to the presence of a natural bitter compound called Cucurbitacin. There are many types or forms of Cucurbitacins present in these fruits.

The Bitterness in cucumber is especially due to the presence of Cucurbitacin A, B, & E. Generally this chemically is naturally present in the leaves and stem portion to prevent the attack of munching insects & animals. Due to certain natural, genetic, and manmade factors some cucumber fruits get bitter.

The Presence of Cucurbitacin makes a Cucumber fruit taste bitter.

Reasons for bitterness in cucumbers?

We have already learned that the bitterness in cucumber is caused by Cucurbitacin. Now you should ask, why did cucurbitacin get accumulated in the fruits instead of just leaves or stem. What actually changed the natural deposition of this bitter compound in cucumber fruits?

Here’s the answer…

  1. Genetic Traits
  2. Extreme Temperature fluctuation
  3. Inappropriate watering
  4. Irregular fertilization
  5. Inadequate amount of Sunlight
  6. Transplant Shock
  7. Shock due to pest or insect attack

Other than these soil condition is also a very important factor in growing healthy cucumbers. You should read: Is Cucumber a Fruit or a Vegetable?- Kitchen Garden Facts

grow Cucumber in may

Genetic Traits

We have learned that Cucumber belongs to the cucurbit family. It contains a common dormant gene that has the potential of making the fruits bitter. Are you familiar with Bitter gourd? If not read my previous post to know more. Bitter gourd contains the same gene but in an active state.

Sometimes you will find only one or two plants out of the whole bunch produces the bitter cucumbers. This time a dominant genetic trait is one possibility.

Extreme Temperature Fluctuation

Cucumber grows in a very confined range of temperatures. It does not like a too hot or too cold climate. In fact, a sudden change in temperature can also cause shock to the cucumber plant.

If you experience a large variation in day-night temperature then this could lead to bitter fruits in the cucumber plant.

Inappropriate Watering

Underwatering and overwatering is the main reason for a shock in cucumber plants. If the soil gets dry and you missed the watering schedule for just a day or two, then you will likely get a bitter cucumber.

Cucumber grows really fast. A fertilize fruit can mature within 5 days. So even if you missed the watering for the first 2 days, Cucumber will get bitter. Once a cucumber plant gets in stress or shock it will produce bitter fruits. The best chance for recovery will take 2–3 weeks. Meanwhile, all the fruits it produces may taste bitter, you can’t stop that.

 Irregular fertilization

Cucumber is a heavy feeder.  It needs more nutrients to grow faster. This continuous demand for fertilization makes it more prone to stress especially if you missed fertilization.

More often over-fertilization is a bigger problem. We all care for our plant but sometimes overcaring is the bigger problem. In the rage to get more and more fruits every week,  we tend to over-fertilize the plants. This forces the plants to sudden stress. It may lead to the fruiting of bitter cucumbers.

Inadequate amount of sunlight

Sunlight is essential for every plant. We gardeners know this- don’t we. Actually, most of the time just knowing is not enough, you have to act accordingly.

Too much sunlight can cause overheating and less can cause wind chill. Technically, sunlight is important for cucumber especially for proper flowering & fruiting.  Less light will reduce flower formation and too much can kill the flowers before fruiting.

Inadequate sunlight can cause stress to the cucumber plant and hence it will produce bitter cucumbers.

Transplant Shock

A cucumber plant getting a transplant shock is very common. There are soft body plants. They are more likely to get stressed during transplantation. It is common but only a few times it can cause bitterness to the fruits.

Rather if you transplant late or either during it start flowering then it may get is the shock and produce bitter inedible cucumbers.

Shock due to pest or insect attack

We know that cucumber and all other members of the Cucurbitaceae family contain cucurbitacin. This compound is important to prevent any pest, bug, or insect attacks.

Sometimes there are some pests and bugs rigid enough to feed on cucurbitacin caring plants. Pests like mealybugs, aphids, or spider mites can infest cucumber plants. This infestation is an important reason for plant shock. ultimately this could lead to cucumbers taste bitter.

checkout my previous post: Top 10 reasons why new gardeners fail- with solution

A Gardeners Guide: Remove bitterness in cucumbers

So… You have read the reason for bitterness in Cucumber. That’s good to know but what to do to prevent bitterness in Cucumber?  We, gardeners, have tried many, really many techniques to avoid this situation. Some of those works and some don’t.


I have come up with just a few of these effective techniques that really work. Remember there is nothing to do once a fruit gets bitter. Instead, we have to act before anything wrong happens. So keep reading…

  1. The best solution for gardeners is to choose cucumber varieties that are less prone to bitterness.  This is an effective modern way to get rid of the bitter situation- straight from the roots.
  2. Make soil well-drained and high in organic compost. A best commercial practice is to cover 2-3 inch (3-8 cm)  topsoil with aged compost and manure. It should be done 1-2 weeks before transplanting or seeding the cucumber in the soil. Raised beds are the ideal way to grow cucumbers. You can follow: Everything to know about raised garden beds
  3. Transplant during the evening to prevent any transplant shock. You can provide partial shade to the plant for the first few days to acclimatize easily.
  4. Water every day without breaking the schedule. Always keep the soil moist and loamy. Never wait for days to dry the soil. Also, don’t overwater. Use your fingers to test the moisture level in the soil. The use of drips & Sprinklers is best for cucumber farming.
  5. Provide shade for summer varieties and adequate heat and sunlight for spring varieties. You should choose a spot near the south walls to adjust with average daylight and temperature. Overall cucumber plant loves humidity.
  6. Provide support like fencing or trellis netting or strings to help cucumber to climb. Support is essential during rainy days. It will also prevent cucumber fruits from insects and grubs.
  7. Fertilize the cucumber plants once in 22-25 days with nitrogen-rich fertilizers. You can try NPK 24:19:19 or less for the best results. Never delay or hurry with this time frame. Regular fertilization is very important for cucumber plants.
  8. Never intentionally cut or prune cucumber branches during the fruiting season. Some gardeners suggest this as effective to increase fruiting quality, yes it does. But if you do something wrong then your plant may get in stress and produce bitter cucumber fruits. Sometimes waiting is better than feeling sorry.
  9. Cover the roots of every plant with 2 inches of mulch or black plastic sheet. This will help to retain moisture and temperature in the soil. Also, this will help to control weed and grass that can feed on essential nutrients.
  10. Use organic pesticides like neem oil spray once every week to prevent any pest attack on the plant. Don’t use chemical pesticide or fungicide.
  11. Finally, harvest the fruits in time. You should be aware of the mature size of fruits for the variety of cucumber you choose. Generally, you can harvest cucumber once the flower is dropped off its head. Late harvesting simply means wasting taste, time, and effort.

Good Quality Non-bitter Cucumber varieties


You can choose the traditional cucumber varieties for ethnic taste. But those varieties are more prone to bitterness. If you want to minimize the chance for bitter cucumber then try the modern hybrid varieties. Some good quality non-bitter cucumber varieties with low cucurbitacin are-

  1. Jazzer
  2. Holland
  3. Lemon
  4. Aria
  5. Marketmore 97
  6. Armenian
  7. Diva
  8. Eversweet
  9. Improved Long Green

You can also ask any seed seller or your local farmer for the best cucumber varieties in your area. Maybe my favorite cucumber seeds will work fine for you- give it a try.

3 Kitchen Tips to remove bitterness in cucumbers

These tips are age-old recommendations from the land of origin of cucumber- India. These techniques can help in removing bitterness from cucumber whatsoever if done correctly. Some people consider these as myths but I think there’s no harm in trying these so it is good to give it a try.

Afterall your cucumber is bitter you can’t do much to avoid that. Isn’t it better if something makes it at least edible? I hope so…

Cucumber fruit or vegetable
Sweet Cucumber

1)  Cutting and Ribing the tip portion

Ok, this really works at least for me. You just have to cut a piece from the stem end and rub it with the rest. The cucumber will release the cucurbitacin with other compounds in the form of white foam. Repeat this step 2-3 times and then rinse off the cucumber carefully.

Sometimes it is advised to repeat this step for both ends. You can do so if you want. Also, some people suggest using a pinch of salt for rubbing. I think it works.

I know, this cannot guarantee 100% removal of bitterness but at least it can reduce enough to be edible. Why not give it a try, maybe it works for you also.

2) Peeling off Cucumber skin

Sometimes just removing the skin portion can greatly reduce the bitterness of cucumber. Cucurbitacin is mostly present beneath the skin of cucumbers. Once removed it can greatly reduce the overall bitterness.

The best approach is to use this method after the previous one. Together these methods can help in getting rid of bitterness from the cucumber.

3) Pickling the Bitter Cucumbers

This is probably the only explainable method. It is effective certainly because fermentation breaks down the cucurbitacins present in cucumber. This is probably the main reason for using the whole cucumber for pickling.

The manufacturers don’t even care for bitter cucumbers. I think it works and has a scientific explanation. Moreover, this method doesn’t solve your need to eat cucumber right away from the garden to the plate. You will have to wait for weeks to get the pickle ready to eat.

Other than this salt or brine treatment is also very effective in removing cucurbitacin from the cucumber.  Again this is not an easy and fast method of eating cucumber. So let it for another discussion. Write down if you knew anything else to solve this situation.

Are Bitter Cucumbers Poisonous?

It is always said, everything that tastes bad is always bad for your tummy. This is also true for bitter cucumbers. It contains cucurbitacin, a natural pesticide very bitter in taste and toxic in nature. Therefore, you can say that bitter cucumbers are poisonous. But are they really that bad?

Certainly not, Bitter cucumber is not poisonous enough to harm us. A high dose of cucurbitacin is harmful and toxic but it may take you to eat more than 10 bitter cucumbers to fall ill. I think no one is that much fond of the bitter taste. Even if you do- you can’t eat that much cucumber at once.

Are bitter cucumbers harmful?- It really depends on the fact, how much you are going to eat. A few bites are no problem but eating 4-5 bitter cucumber will make you feel yukky. Eating More than that can lead to food poisoning.

Can bitter cucumbers make you sick?-Yes, it can but only if you eat like a horse. Too much eating is always harmful to your tummy. Similarly excess of bitterness can make you sick.

Does rubbing the end of cucumber make it less bitter?-  Yes, It really works. I have tried rubbing the ends of cucumber with a pinch of salt. Sometimes it makes the cucumber less bitter. Maybe it is effective or maybe it’s just a psychological belief that works. I really trust this method. You can try and please share your honest opinion with us.

Read this: How to grow button mushroom at home?

Final Word

I think for gardeners, it will always be a haunting thought of getting a bitter cucumber from their plants. But it is not that difficult to handle this situation. With some precautions and proper care, you can easily grow healthy cucumber without any bitterness.

Even if you get a bitter cucumber, this does not mean you have failed completely. You can still make the changes to improve. Also, you can use part of the cucumber as not the whole cucumber is likely to taste bitter. Getting a bitter cucumber intentionally is very rare so don’t panic, act accordingly.

Write down your comments and views. I’ll be back with more interesting topics on vegetable gardening. Till then Kepp reading keeps gardening!


Hi, My name is Sukant. I am an I.T professional. Gardening for me is not just a hobby, it's a way of living life with nature. My Ancestors were Commercial farmers: So I personally feel attached to the green. I am not an expert, I'm here only to share my gardening experiences. It's always Refreshing.

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