Chlorosis is an infection that spares neither young nor mature cucumbers, wherever they grow. Leaves affected by the disease turn yellow, dry and wither, and then fall off. The bush remains bare. This disease has many causes, several types, but, fortunately, there are successful treatment algorithms.
Causes and signs of appearance
Signs of the disease are found on the upper and lower leaves, even if they are underdeveloped. Primarily cucumber becomes infected through the rhizome. First, blurred or angular yellow spots appear on the edges of the plates. Over time, the foci brighten, and only the streaks of the plate will be green. Very quickly, the tops will turn yellow all over and dry out – alas, this disease develops rapidly.
However, how quickly the infection spreads also depends on the immunity of a particular borage. If the bush is strong, the symptoms will manifest themselves within a week, and this will be before the onset of the active phase. But a weakened bush may already die by the fifth day, and sometimes three days is enough for the death of the plant.
The source of the problem is the lack of chlorophyll in the tissues, and it is he who is an active participant in photosynthesis, due to which the tops turn green.
Why there may be problems with the production of pigment:
- lack / excess nutrition;
- weak or excessive watering;
- diseases that weaken the immunity of the plant;
- weather disturbances – for example, persistent heat or, on the contrary, a prolonged cold snap;
- a sharp change in temperature;
- a site that is open to winds and drafts;
- planting borage in the shade.
Chlorosis quickly and quite sharply inhibits cucumbers, they immediately stop developing, do not form new ovaries, and all formed ones wither. Leaves can even curl in places.
But the symptoms may vary slightly depending on what specifically caused the disease. For example, if the lack of light is to blame, the entire bush will probably turn yellow. Leaflets will form, but remain small, but the whips, on the contrary, will be disproportionately long. They also face significant thinning.
If the cause of chlorosis is excess moisture, the plant looks like this: turns yellow, the tops fade, serous foci appear on the plates. An emergency normalization of irrigation is needed, because if this is not done, a fungus will appear on the lashes.
But chlorosis can also cause frostbite when the temperature drops sharply: then the leaves lose their color entirely (less often – zonal). Well, if a plant is affected by a spider mite, a pale, nondescript cobweb can be seen on the back of the yellow leaf.
Types
And chlorosis is different in that nutritional deficiencies manifest themselves in different ways: depending on the lack of a particular element, signs of the disease appear.
There are several types of chlorosis.
- Magnesium. If the plant lacks magnesium, the reverse side of the leaf plates will first brighten, but the veins will still be green. In the future, brightening will affect the entire plate. Over time, the edges of the leaves will acquire a dark pink color.
- Iron. Iron deficiency leads not only to lightening of the leaves – the stems at the tops of the lashes also lighten, and their color eventually becomes reddish-brown.
- Nitric. The tops at the bottom of the bush will turn yellow first, and the infection will go up. The plants will turn completely pale, and if the defeat becomes significant, they will also turn brown (and the veins too).
- manganese. The lack of manganese is visible by the way the tissue between the veins becomes light green (or yellow), and a dirty yellow or rich orange tint appears along the edges of the plate.
- Potassium. With a lack of potassium, the lower leaves begin to turn pale first, along the edges of the leaf plate it becomes light green, and then turns brown.
- Zinc. Between the veins, sections of the leaves turn yellow, and then the tops begin to turn brown. The leaves first turn gray, then orange, and this orange hue may resemble a bloom.
Whatever caused the infection, the affected parts of the plant can no longer be saved, they must be removed and removed from the site.
Treatment
It will consist of two fundamental points: the application of fertilizers to change the nutritional balance and the elimination of the causes. One does not exist without the other, so you will have to work on all fronts.
Application of fertilizers
If the diagnosis is made correctly, and, after consulting the description, the owner of the garden understood what was the matter, he will simply give the plant what it lacks.
- With iron deficiency (and this is perhaps the most common cause of infection) you need to use special drugs. These are Ferrilen, Ferovit, Micro-Fe complexes. Iron vitriol will also help cure cucumbers. And on its basis, you can prepare the following composition: dilute 1 g of vitriol and 4 g of lemon in 2 liter of pure water, stir the mixture until smooth, pour cucumbers under the root. And in order to urgently increase the level of iron, the soil is sprinkled with rust (it can simply be removed from old nails). Sometimes these same nails are completely buried in the ground.
- With a lack of magnesium Magnesium nitrate is the best remedy. You need to make a solution like this: stir 10 g of top dressing (in dry form) in 10 liters of water, wait for the sediment to dissolve completely, pour cucumbers under the root a liter per bush. The solution also includes nitrogen, but it is still appropriate for any growing season, because there is little nitrogen in the composition. And you need to continue to treat the plant until the cucumbers recover. The interval between feeding injections is 2 weeks.
- With a lack of nitrogen organic mullein can be a lifesaver. 10 g of manure is diluted in a bucket of water, everything is mixed and watered under a bush so that each plant has 1 liter of liquid. Twice a month, cucumbers are sprayed with 2% calcium nitrate.
- With sulfur deficiency saves magnesium sulfate. In a bucket of water, dissolve 35 g of fertilizer, mix everything well and pour borage with this composition 2 times a month. But if chlorosis is not just manifested, but the disease is already pronounced, spraying over the bush will help get rid of it: for 10 liters of water, 20 g of the product.
- With a lack of manganese potassium permanganate solution helps a lot. It is necessary to dilute a small amount of powder with water until it becomes light pink (too dark solution will not work). And with this water it is necessary to water the cucumbers under the root every 2 weeks until the ailment recedes. Any top dressing is applied only on moist soil.
Chlorosis is treated not only with top dressing. It is important not to miss the moments of agricultural technology: if the roots have moist soil, you need to reduce watering – they are unnecessary. If chlorosis is caused by a lack of iron or nitrogen, the soil can also be acidified. And it is always useful to loosen the soil and remove weeds along the way.
The picking of young seedlings will also help fight the disease: cucumbers should not grow very densely, this interferes with them.
Elimination of causes
As already mentioned, alkalization of the soil can become a problem. If this happens, the plant will not absorb nitrogen and iron. And only acidification (acidification) of the soil will be timely. Cucumbers should be watered under the root with nitric-phosphoric acid. In a 10-liter bucket, dilute up to 5 cubes of acid. This is the easiest way to treat the soil for acidification. And in the open field, you can do this, and in the greenhouse.
Perhaps the cause of chlorosis was poor drainage. And this can also be overcome by drying the earth – everything is elementary. It is necessary to organize and proper watering so that the roots do not soak.
The picking is useful, but if it is carried out inaccurately, problems can also arise. It’s just that the roots of the plants will be damaged during transplantation. And until they recover (which takes time), the plant simply will not be able to take nutrients from the ground. More precisely, he will not be able to take them so as to get enough. Help is this – you need to speed up the recovery of the cucumber, using the “Clean Sheet”, “Radiofarm” and other similar rooters.
Preventive measures
An integrated approach to the treatment of chlorosis is, of course, good. But it is better not to allow the disease at all. There are 3 simple rules to save:
- you can’t plant cucumbers very often – they need to “breathe”, they need a place and need light;
- you can plant them only in a sunny place, they get sick in the shade;
- it is necessary to water the cucumbers, but only moderately, because waterlogging is a quick path to disease.
And, of course, increased, excessive feeding can also lead to infection of the plant: it will weaken from hypernutrition. You also need to be prepared for unexpected moments, like a sharp cold snap. Flash frosts cause discoloration on the leaves. The bush can still be restored, but only by removing all the affected areas from it.
But it is better to be very careful when choosing the moment for transplanting seedlings: heat should not be the first deceptive, but already established.
