by If the onions in your garden are turning yellow, don’t worry – we’ll tell you what to water and feed them with to save the harvest.
The change in color and wilting of onion feathers at the end of the season is a natural process. But sometimes it happens that onions turn yellow in an “emergency mode” – in spring or summer. In this case, it is necessary to take emergency measures.
To prevent onions from turning yellow, you can use both folk remedies and heavier “artillery”. We’ll tell you about everything in order.
Mistakes in onion care
The most common reason why onion tips turn yellow is a simple oversight. Perhaps you are simply not caring for your onion bed correctly?
Insufficient watering
If the onion suddenly starts to turn yellow and the soil in the garden bed is dry, most likely the problem lies in the fact that the plant is suffering from “thirst”.
Control measures: Observe the watering regime. In the first half of summer, onions are watered twice a week, in the second half – once a week. The watering rate is 6-8 liters per 1 sq.m. Naturally, in dry weather, the garden is watered more often. Onions are watered with water at a temperature of 18-25 ° C directly under the root, preferably in the first half of the day.
When the top layer of soil dries out, the bed needs to be loosened.
Nutrient Deficiency
Another possible reason why onion tips turn yellow is a lack of micro- or macroelements in the soil.
As a rule, it is most often a matter of nitrogen deficiency. With a deficiency of this element, onion feathers grow short and thick. At the same time, their color is not healthy green, but yellowish.
Control measures: How to feed onions so that they do not turn yellow? Nitrogen-containing fertilizers. It is best to use organic matter – an infusion of manure and urea (for 10 liters of water take 1 cup of rotted mullein and 1 tablespoon of urea and leave for several days).
Pests of onions
Unfortunately, the problem of yellowing onion feathers cannot always be solved by adjusting the watering and fertilizing regime. Sometimes the culprit is an invasion of insect pests.
The stem nematode
Wondering why the onion feathers are turning yellow and wrinkling? Try ripping open the “unattractive” leaf. If you find small white thread-like worms inside, you should know that your onion has been attacked by a stem nematode, one of the most dangerous onion pests.
Control measures: Unfortunately, only high-quality preventive treatment of the onion sets and soil before planting helps in the fight against nematodes. In the summer, when the larvae have migrated from the bulb to the feathers, all that remains is to immediately burn the affected plants to prevent the pest from ruining the entire onion crop.
Onion moth
Onion moths lay eggs at the base of leaves or on the soil near onions several times per season. The first generation of these insects begins to harm crops in late spring – early summer.
If you find small yellowish caterpillars with brown warts inside a yellowed onion feather, then the problem is onion moth infestation.
Control measures: Considering that the pest overwinters in the butterfly stage, treating the bulbs will not help prevent damage to the plant. In this case, it is necessary to treat the bed with an insecticide, for example, Iskra (1 tablet per 10 liters of water, 1 liter of solution per 1 sq.m.).
Lukovaâ flies
Onion fly actively attacks the plant in spring – in April-May. The main symptom is when the tips of the onion turn yellow first, and not the entire feather. If you dig up the plant, you can see that the bulb has rotted.
Control measures: Unfortunately, as with most pests, it is easier to scare them away from the garden bed than to try to save already damaged plants. In the case of onion fly, dusting the row spacing with a mixture of tobacco dust and sunflower ash, taken in equal parts, will help. Of the preparations, try Alatar. Affected plants are dug up and burned.
In addition, rows of onions can be alternated with rows of carrots – these plants repel each other’s pests.
Onion with secretive trunk (weevil)
If the onion feathers have turned yellow and passages are visible through the skin, the plant is being eaten away from the inside by the larvae of the onion beetle. These are legless yellowish-white caterpillars with a brown head, up to 0,7 cm long.
Control measures: If you notice beetles on the leaves, you can collect them to prevent them from laying eggs in the feathers. As a deterrent, it is also useful to mulch the soil around the onion plantings with ash, mustard powder, ground black and red pepper. During the period of beetle settlement, treat the plantings with Alatar or Fufanon-Nova according to the instructions. The only thing left to do is to burn the plants eaten by the larvae.
Onion thrips
Onion (or tobacco) thrips are tiny, up to 1 mm long, but very dangerous pests of all kinds of garden, vegetable and ornamental crops. When affected, whitish spots form on the leaves, which later merge, and the leaf fades.
Control measures: As a deterrent, onion plantings are sprayed with an insecticide (Iskra, Confidor Extra, etc.). Before planting, the bulbs are disinfected in hot water (dipped in water at 10°C for 45 minutes), and then washed in cold water. Damaged plants are burned.
Onion diseases
Onions can fall victim not only to voracious pests, but also to all sorts of diseases. If you notice the first signs of illness, act immediately!
Bacterial rot
Bacterial rot always comes “packaged” with thrips, onion flies and other pests – it is the insects that infect the bulbs with this disease. Symptoms of bacterial rot: wilted, yellowed onion feathers, dried flower stalks and a rotten bulb.
Control measures: In the fight against bacterial rot of onions, only preventive measures will help: discard infected bulbs, treat them and the soil before planting, and burn affected plants.
Bottom rot
First of all, the yellowing and dying off of the onion tips is noticeable. If you dig up the bulb, you will see white mycelium on the bottom. When the rot has advanced, pink mycelium appears between the scales, and the bulb itself becomes soft and watery.
Control measures: The bulbs are treated before planting (soaked in a fungicide). Diseased plants are burned.
Rust
Symptoms of rust usually appear on onion leaves in May-June in the form of yellow spots, which soon develop into raised pads. As the disease progresses, the feathers turn black and fall off.
Control measures: Only prevention is effective in the fight against rust. In addition to pre-sowing treatment of bulbs and soil at the beginning of summer, spraying with a soap solution of copper oxychloride is also carried out (1 tablespoon of the preparation and liquid soap per 10 liters of water). After a week, the treatment can be repeated.
The vagaries of the weather
“Nature has no bad weather,” goes a famous song. But the vegetables in the garden don’t think so! Prolonged rains, prolonged drought, abnormally cold and too hot summers have an equally bad effect on the harvest. For this reason, family onions, bulb onions, and leeks turn yellow. Alas, there are no onion varieties that are completely resistant to the vagaries of the weather.
Control measures: All that remains is to hope for the mercy of nature towards the onion crop, to water the onions in time during the heat and to cover them during recurrent frosts and severe cold snaps.
Please note that in the case of onions, troubles never come alone. Insect pests not only “cohabit” in the same garden bed, but also spread diseases, so it makes sense to carry out comprehensive prevention:
- soak the bulbs in a fungicide solution before sowing,
- cultivate the soil, spray the onions after planting,
- mulch the soil with ash,
- pollinate it with tobacco dust,
- destroy infected plants in time.
And, of course, don’t forget about good watering and feeding!
We hope that our brief reminder about why onions turn yellow and how to deal with it will be useful for you and will help save the onion crop from diseases, pests and adverse weather conditions.
