Why yellow tips of the pen in the bow and how to fight it
As mentioned above, if the onion started to turn yellow at the end of the season, after a couple of months after planting, then there is nothing to worry and deal with this phenomenon is not necessary, however, if such started to happen in early summer, when the feathers had just reached the height of its maximum, in this case, it is crucial to address the causes.
In most cases, the early yellowing of feathers is due to the lack of nutrients in the soil, especially due to the lack of nitrogen. If a long time the weather is dry, be sure water bow, because plants can soak up this element solely in dissolved form. Excessively rainy weather also affects Luke, because in the rainy season nitrogen is removed in the lower layers of the soil and the plants begin to turn yellow from its absence. In this case, the only way - by feeding culture of the special nitrogen-containing drugs. Well-proven urea, nitrate Amon, means "Kristalin", and also extracts of mullein and weed.
To yellow tips of the feathers can and pest. Onions are often attacked by onion moth, onion thrips, onion nematode, but most of the onion fly. To check whether the infected culture is the last of the pests, remove the yellow pen, and tear it along. If you see white grubs, remember that this is the onion fly. If the pen is clean, remove from the earth the bulb and test it: the dilution of the inside of the vegetable - a sign of the defeat of his onion fly. Damaged plants must be removed from the garden, so they do not infect others. After cleaning follicles of the patients sure to spill the soil with salty water (200 grams of salt per 10 liters of water), repeat after 5-7 days.
It should be noted that yellow onion can because of the acidity of the soil. Nitrogen is poorly absorbed in acidic soil, and the potassium in it is very small, so choose for planting onion alkaline or soil before each watering spray ashes between the rows, and every two or three weeks, apply fertilizer with nitrogen and potassium.