The bitterness in cucumbers is due to the production of a biochemical compound - cucurbitacin (a saponin from the group of glycosides), and this is a feature of the pumpkin family, developed genetically as a protection against being eaten by animals before the ripening period begins.
The substance is also present in small quantities in non-bitter fruits - cut off the green butt of a cucumber 1 cm and intensively rub it at the cut site - a white foam will appear - this is cucurbitacin. Saponins are intensively produced from the moment of seed germination, and are present in all parts of the plant - stems and leaves; in young, unripe fruits there are more of them, but when ripe, the need for such protection disappears, and bitterness is not felt.
Scientists have already identified nine genes responsible for the formation of this glycoside, and therefore we can definitely say that there are varieties that are not prone to the formation of bitterness. Cucurbitacin is a rather toxic compound, but at the same time it has antitumor, anti-inflammatory and antimicrobial properties. Eating bitter vegetables in large quantities can cause diarrhea, rumbling and abdominal cramps. Biochemical substances from cucumber (not only cucurbitacin) penetrate into breast milk, nursing mothers should remember this.
By the way, you know that cucurbitacin is contained in small quantities in sweet watermelons - the pulp of a ripe watermelon contains 0.5% cucurbitacin, but we do not feel this until we overeat these berries or eat a piece of unripe watermelon.
Why does bitterness accumulate in ripe cucumbers? One can explain the bitter taste of greens and seedlings (the cotyledon leaves are especially bitter), but the bitterness in ripe fruits depends entirely on external factors, if it is not a stable hybrid. The production of cucurbitacin is a response to stress. For this crop – improper watering, temperature, nutrition, and it doesn’t matter whether you grow vegetables in a greenhouse or open ground.
Cucumber comes from tropical and subtropical regions of India, places where the air is humid and there is no scorching sun. Therefore, it should be grown in a shaded place, in diffused light. It can be protected from the sun by the openwork shade of fruit trees, specially planted crops, for example a row of corn, or translucent material - for these purposes the industry produces a special covering material - spunbond. Very often, gardeners use it to protect cucumbers from the cold, stretching it over the arcs or frame of the greenhouse, and as soon as warm weather sets in, they remove it. Of course, if you leave a greenhouse, on hot days the cucumbers will overheat and, as a result, there will be bitterness in the fruits, but you should leave the spunbond if you have a sunny side, just don’t throw it over the vegetable bushes, but stretch it like a screen for protection on sunny days.
The cucumber is stressed by heat and dry air. If such weather lasts for several days, a week or longer, the leaves of cucumbers turn yellow and dry out faster, the fruits do not have time to accumulate enough moisture, they are characterized by curvature of the tips, and of course, they begin to taste bitter.
During this period, it is very important to water the bushes abundantly with warm water - the optimal time is early in the morning and in the evening at 17-18 hours. Watering twice a day is more effective. However, it is more difficult to get warm water in the morning - it cools down in bathtubs, barrels and a centralized system, while from a well it is icy. Therefore, gardeners usually water in the evening, when the water has time to warm up, but this may not be enough.
To reduce the impact of unprecedented heat, you can make a canopy over cucumbers in open ground, but only from white or mirror material. And for greenhouse cucumbers it is convenient to use a mirror film - it is moistened and glued to the glass of windows in houses, it is transparent on one side and completely reflective on the other. To prevent the roots of cucumbers from drying out, you need to regularly, once a week or a week and a half, mulch the bushes with fresh soil, in addition, this causes new growth of roots and prolongs fruiting.
Do not plant cucumbers in dense clay soil, but plant them in the loosest soil. If you have loam, don’t be lazy and bring a cart of peat. Not sand, but peat. Lowland is better suited, but in its pure form it is slightly sour; it needs to be weighed, for example, with wood ash - 2 cups per bucket of peat. Although, it is better to focus not on the eye, but on litmus paper - cucumber loves acidity pH 5.0 - 6.0.
There is an opinion that cucumbers respond very well to feeding with fresh manure. In fact, this is not so, and even vice versa - fresh organic matter can provoke the production of bitterness. These vegetables are very gluttonous and organic fertilizers are just right for them; cucumbers, like pumpkins and zucchini can grow perfectly right on a compost heap, but you should feed them with rotted manure, not fresh manure. It is better to prepare the beds in the fall by laying in fresh manure; by spring it will be “prepared” just right. If you really want to add fresh organic matter to avoid bitterness, you need to water the bushes very generously and not let them dry out even for a short time.
For summer residents who visit their gardens intermittently, the main cause of bitterness is uneven watering. And in greenhouses and greenhouses there is also overheating. The cucumber does not like alternating drought and abundant watering; it is historically accustomed to even conditions. For him, stress is sharp extremes in soil moisture, air and temperature. Therefore, sometimes, when summer is characterized by changeable weather, cucumbers grow better on glazed balconies than in open ground - we close the balcony at night and open it in the morning, water it as it dries - the cucumbers grow and do not become bitter.
Unfortunately, if one bitter fruit appears on a cucumber bush, then the whole batch will become bitter and the harvest from it is only suitable for processing. If you notice deformation of fruits on green plants, you should think about what’s wrong - this is one of the signs of heat, insufficient watering or excess fertilizer. Deformed fruits are more often bitter than well-formed ones. Let's summarize all that has been said; in fact, all the reasons can be reduced to a short reminder for the gardener. Cucumbers are bitter because:
There are other answers that seasoned gardeners often give, such as lack of nutrition, especially nitrogen and potassium. In fact, this is far from an indicator; due to a lack of nutrients, few fruits are set, cucumbers grow more slowly, the bushes are small, but this affects bitterness only together with other factors.
You cannot feed a cucumber if it has already experienced stress - in extreme heat or from dryness; wait a week or two until it recovers. Some people don’t understand why bitterness comes from the sun. In fact, not from the sun as such, but from the heat, i.e. The cucumber is not afraid of a lot of sun in the morning, before 11 o’clock, or in the evening after 17 o’clock. During the day, the sun is dangerous only on hot days, when the temperature in the shade is 27-28 degrees, and at the beginning of summer and at the end of August, when there is no extreme heat, any sun is beneficial for cucumbers.
In addition to the main reasons, there are those that many people forget about, but in vain. For cucumbers, the composition of water is very important - they do not tolerate excess iron and calcium, and do not tolerate chlorine and sodium at all. These elements inhibit any melons, but cucumbers in the first place.
Some varieties have a stronger tendency to accumulate cucurbitacin, others have a weaker tendency, and there are varieties that nothing can make them taste bitter - neither a delay in watering nor heat:
By the way, there is an opinion that varieties of cucumbers for pickling are practically not bitter, unlike salad varieties. This is not so, among salad varieties there are many varieties without bitterness - the most popular, Chinese varieties, which are sold in stores, are long like sticks with small seeds. These varieties are: Chinese Heat-resistant F1, Chinese cold-resistant F1, Chinese farmer and others. They are suitable not only for salads, but also for canning, only because of their large length, you have to marinate them in slices, cutting them lengthwise or crosswise.
You have harvested the crop and discovered bitterness, naturally such cucumbers are unpleasant to eat in a salad, there are three options left:
No matter what spices you add to the salad, if there is a bitter cucumber, it will be felt, so for a fresh salad - only long soaking. But if the whole cucumber is not bitter, but only from the tail, you can try to reduce the bitterness in this way: cut off the green butt 1-1.5 cm and rub it vigorously at the cut site until the foam stops coming out. Now rinse the cucumber. It's not clear how, but it helps. But you can pickle according to any recipe, cucurbitacin is destroyed during heat treatment, there will be no bitterness. The bush from which bitter cucumbers were collected should be given special attention:
It would seem that what could be easier than growing cucumbers: planting, watering, picking, eating. But everything is not so simple: it turns out that cucumbers are very capricious plants. And even fruits grown in a greenhouse can be bitter. But there they are in more comfortable conditions than in the garden. So what's the reason?
Cucumber is native to the tropical and subtropical regions of India. Its wild relatives still grow in their natural habitat. Only their fruits are small and not so tasty. Under natural conditions, cucumbers prefer shaded areas of the forest, with well-moistened soil. If cucumbers are in favorable conditions, their fruits, still unripe, are greens, quite pleasant to the taste and are a favorite delicacy for herbivores.
To avoid bitterness, cucumbers need to be properly cared for. But if cucumbers grow in an unsuitable place and experience stress, then the natural mechanism of preserving the species is activated and, therefore, they need to move from this unfavorable place to another. The spread of cucumbers in nature occurs by endozoochory: the animal eats fruits with mature seeds and throws them out with excrement to a new place.
To migrate to a new location, the plant must protect its seeds until they are fully ripe. In this case, cucumbers produce a substance that gives the fruits bitterness - cucurbitacin, which accumulates mainly in their peel. Two genes regulate the production of cucurbitacin:
Bitterness accumulates in the skin of the fruit To prevent cucumbers from producing cucurbitacin and becoming bitter, you need to create comfortable conditions for them, but for this, all the basic factors necessary for the life of the plant must be met.
Attention! Here are the main mistakes made in growing cucumbers that contribute to the production of cucurbitacin.
So, cucumbers will be bitter if in a greenhouse:
Factors contributing to the appearance of bitterness must be eliminated comprehensively Cucumber is a stenobiont plant, in other words, it grows and develops well in stable, favorable conditions.
According to the science of agricultural technology, in order to grow a bountiful harvest of tasty cucumbers, and not wonder why cucumbers in a greenhouse are bitter, you need to properly care for them - water them on time, fertilize them correctly, create comfortable conditions and not expose them to stress.
Do not forget that feeding plants is a very important component of care. Attention! Below are the rules for growing cucumbers without bitterness.
The soil in a greenhouse will deplete faster than in an open garden bed, so fertilizer needs to be applied more often, and most importantly, regularly. It is enough to feed the cucumbers every 7-8 days using liquid solutions of mineral fertilizers: nitrogen, calcium, potassium. It is not recommended to use manure for fertilizer. Loosening the soil from time to time is very useful - this is the so-called dry watering, as a result of which the roots of the cucumbers are saturated with oxygen.
To prevent cucumber greens from becoming bitter, you need to water the plant in a timely manner. From the beginning of flowering until its end, you need to water once every 3 days, and during the fruiting period - every other day. Water for irrigation should be warm. It should be borne in mind that during hot periods you need to water more often, and, accordingly, on cool days - less often. Keep the soil moist - it should not dry out. The depth of the moistened soil should not exceed 15 cm.
Drip irrigation of cucumbers Approximate water consumption per 1 sq. m soil:
It is advisable to water not only the roots of the plant, but also the stems - cucumbers love water. Spraying the plant in the morning is very useful. You can spray the walls of the greenhouse and paths. But you shouldn’t get too carried away - excess moisture is just as harmful as its lack. Therefore, the greenhouse must be ventilated, but this must be done on warm, windless days, when the air temperature outside is approximately the same as in the greenhouse.
We should not forget that cucumbers are a plant from the tropics and love warmth. This means that you must observe the temperature regime, namely, maintain the temperature not lower than +20 degrees, and at night not lower than +18. During fruiting, gradually raise the temperature to +28 degrees.
If the sun is too strong, cover the greenhouses with white cloth Temperature changes should not be allowed, so the greenhouse must be heated so that during a sharp cold snap outside, the greenhouse remains at the same temperature. If the fruits of the cucumbers are supercooled, the greens will taste bitter.
Cucumbers do not like extreme heat and scorching sun. Therefore, in order not to be upset about the scarcity of the harvest, gnarled or bitter fruits, it is better to take precautions. In too hot summer months, it is advisable to whiten the film or glass of the greenhouse with a thin solution of chalk and water. In this way, the necessary shading will be provided for the stems. in the greenhouse it is necessary at such a distance that the shoots do not interfere with each other. The optimal distance between the stems is 20-25 cm. As the bush develops, it must be properly shaped to prevent excessive branching. To do this, remove unnecessary side shoots, as well as excess tendrils and flowers. Also, as they grow, it is necessary to straighten the lashes in a timely manner so that the fruits receive a sufficient amount of light.
Advice. In order for cucumbers in a greenhouse to produce a good harvest, you must follow all the above rules. Then the cucumbers will not plot to “escape” from the greenhouse and produce cucurbitacin, and the fruits will be tasty, juicy, sweetish and without bitterness.
Cucumber is a tasty and healthy vegetable. Everyone knows this. However, many often face the problem of bitterness in fruits and do not know what to do about it. Harvesting such vegetables leaves an unpleasant aftertaste. Of course, you can eat bitter cucumbers without the skin, because it is easy to cut off with a knife. But, it is worth considering that peeled vegetables are less healthy. It is the peel of cucumbers that contains most of the micro- and macroelements, as well as nutrients. Therefore, the problem of bitterness can and should be fought. This is what our article is about.
Unfortunately, both greenhouse vegetables and those grown in open soil are susceptible to the appearance of bitterness in cucumbers.
There are different opinions among gardeners and gardeners regarding the nature of the origin of the bitter taste of cucumbers. Some believe that the soil, or rather its composition, is to blame. Others are convinced that the bitterness in cucumbers is caused by a lack of water or nutrition. And some are sure that everything depends on the type of vegetable.
Science has an answer to the question “why are cucumbers bitter?” It is believed that the bitterness appears due to the accumulation of the substance cucurbitacin in the skin of the vegetable. The brighter the sun shines, the more this substance accumulates, and cucumbers become very bitter. This explanation will satisfy those who grow plants in open soil. But why are there bitter cucumbers in the greenhouse, and what can you do about it?
It has been proven that the taste of vegetables depends on the conditions of care. Ideally the right conditions are not always created in a greenhouse, which is why cucumbers develop a bitter taste. After all, in order to get a good harvest in a greenhouse, you need to organize proper watering, timely fertilization, set the optimal air temperature and not injure the plant.
In addition to the above reasons (insufficient moisture, dry air, dryness and decreased soil fertility), a number of other factors contribute to the bitterness of fruits:
In order to avoid wondering why cucumbers are bitter after harvesting and while eating fruits, this phenomenon must be prevented.
You can avoid bitterness if you water the plants with heated water, increasing the amount of watering in hot conditions. When the plant is “young”, it is enough to water it a couple of times a week, and during flowering it needs to be watered daily. Moreover, it is advisable to do this in sunny conditions with open windows. If necessary, the walls of the room can be sprayed with water.
In addition, the bed with plants must be periodically plowed and fertilized (potassium nitrate or Ecoberine are excellent). You need to feed a plant in a greenhouse more often than in open ground, on average once a week.
It is important to establish the correct temperature and humidity conditions in the greenhouse. At night, it is optimal to maintain the room temperature at 18–22 degrees, after which it should be raised to the daytime level of 24–28 degrees. That is, a heated greenhouse is best suited for growing cucumbers.
Pinching cucumbers is very important when forming a bush. In a greenhouse, this process increases yield and prevents overcrowding. Usually the side stems, tendrils and female flowers are removed.
We can say that the main prevention of bitterness is the eradication of the causes of this phenomenon.
Breeders are trying in their own way to solve the question of why cucumbers are bitter. To prevent cucurbitacin from being produced, they breed special varieties of vegetables with a specific gene. It is very easy to purchase seeds of such fruits. Information about this is indicated on the label. Gerasim F1, Garland F1, Doka F1, Egoza F1 - these are some varieties that are not susceptible to bitterness. These cucumbers do not have as distinctive a taste as regular vegetables, which are prone to cucurbitacin accumulation.
There are several simple methods that are used to make cucumbers not bitter.
Firstly, before eating, you can cut off the “tails” from vegetables. This method is effective, since bitterness accumulates at the point where the stalk is attached to the vegetable.
Secondly, you can cut off the ends of the cucumber on both sides and put the vegetables in salt water.
Thirdly, you can cut off the skin of the fruit. It will become less useful, but not bitter.
Do not forget that bitter cucumbers can be successfully pickled and canned. After all, the unpleasant taste disappears during heat treatment.
So, now you know why cucumbers are bitter and how to grow sweet fruits in a greenhouse. It is not difficult to get an excellent harvest if you follow all the recommendations and rules. Do you want to please your family and friends with homemade vegetables? It is in your power to do everything to ensure that the cucumbers from your garden are the most delicious and healthy.
Listen to the opinion of an expert from the Sadovod newspaper about the causes of bitterness in cucumbers and the possibilities of preventing them.
Probably all gardeners have encountered such an unpleasant surprise as bitter cucumbers. This happens quite often. Of course, you can eat such cucumbers by removing the skin, but then you will be left without vitamins and useful minerals, because it is the peel that contains most of them. So what to do, and why are cucumbers bitter? They grew in a greenhouse or in a garden - it doesn’t matter. In this article we will talk about the reasons for this phenomenon and ways to eliminate it, and also talk about how to care for greenhouse cucumbers to avoid a bitter taste.
What people say
Among amateur gardeners there are different opinions on this matter, and they all contain some truth. Some people think that the composition of the soil is to blame. Some people think that cucumbers lack nutrients or water, while others believe that it depends on the variety.
What Science Says
From a scientific point of view, there is also an explanation. It has been proven that the cause of bitterness in cucumbers is a substance that accumulates in the peel. It's called "cucurbitacin". Moreover, the brighter the sun shines, the more cucurbitacin accumulates, and the more bitter the cucumbers become. This is also a scientifically proven fact. But in a greenhouse, there is no sun there? It turns out that improper care is also the cause of the bitterness of this vegetable, and all the necessary conditions are not always met in the greenhouse.
Proper care - delicious cucumbers
From the point of view of agricultural technology, in order to get a rich harvest of cucumbers in a greenhouse, they need to be watered correctly, fertilized on time, monitor the temperature, and most importantly, do not expose the plant to stress.
In order not to be tormented by the question of why cucumbers are bitter, follow these recommendations in the greenhouse:
Water generously and only with warm water. At an early age of growth, do this 2 times a week, and during the flowering period - every day. If the air is not humidified enough, you can spray it on walls and paths. It is advisable to water when the sun is shining outside, but leave the windows closed.
In a greenhouse, the soil is depleted faster than outside, so you need to feed cucumbers more often. Once a week, use liquid mineral fertilizers, potassium, calcium, nitrogen (but not manure).
The temperature in the greenhouse should be no lower than 20 degrees during the day and 18 degrees at night (before fruiting), and then it should be raised to 28. Sudden changes in temperature are stressful, which can make cucumbers taste bitter. It is better if the greenhouse is heated.
When forming a bush, you need to know how. In a greenhouse, this process is especially important, as it allows you to increase productivity and limit the branching of the plant. To do this, remove the lateral shoots, female flowers and tendrils. They only delay the development of the bush and take away the nutrients so necessary for the growing season.
Breeders, who are also concerned about why cucumbers are bitter in greenhouses, have developed salad varieties that contain a special gene that prevents the production of cucurbitacins. Well, if you still couldn’t avoid bitterness, then don’t be too upset, since such cucumbers are suitable for pickling. When cooked, the bitter taste will disappear.
