We protect potatoes from late blight and wireworm

we protect potatoes from late blight and wireworm Blog

The most dangerous potato diseases in the garden are late blight and alternariosis, and the most annoying pests are the Colorado potato beetle and the larvae of the wireworm beetle.

Late blight begins to appear, as a rule, on the lower leaves of potatoes in the form of blurry weeping spots, first along the periphery, and then over the entire surface of the leaves. A distinctive feature of the disease is a white coating on the border of healthy and affected tissue. Similar spots sometimes form on the upper leaves. Browning of the upper part of the stems and peduncles is also observed. In the future, the disease spreads to the whole plant: it fades, turns black, dries up. With a strong development of the disease, mass infection of tubers in the soil occurs both during the growing season and during harvesting.


Alternariosis . Between the veins on the leaves appear dry rounded spots of different sizes. The leaf tissue between the spots turns yellow, the leaves dry up. Dry oblong grayish-brown necroses are formed on the stems, which sometimes cover the perimeter of the stem, it breaks off and dies.

Late blight develops in the garden mainly at high humidity, Alternaria – in hot, dry weather.

Measures to combat late blight

Against late blight (even in the absence of the disease), potatoes begin to be processed when the tops close, that is, almost from the end of June. We offer two processing options.

  1. Spraying with a daily infusion of wormwood (1 part of fresh plants to 3 parts of water) or a decoction of common goutweed (1: 4), boil for 15 minutes. In both cases, 40 g of laundry soap per 10 liters are added to the working solution. Processing is carried out continuously until harvest after 10 days.
  2. The first treatment of plants is carried out with one of the drugs of systemic contact action: arceride, oxychome or ridomil MC. The second – after 10-12 days with contact drugs: ditan, cuprsate, medex or Bordeaux liquid. For subsequent sprayings, the same preparations are used every 8-10 days.

Only chemical control measures are effective against alternariosis. Contact preparations are used, and treatments are carried out at the same interval as against late blight. It is necessary to start processing when the first signs of the disease appear.

With simultaneous damage to plants by late blight and Alternaria in the garden, only chemical treatment is used according to the second scheme.

To increase the resistance of plants to both diseases at the beginning of budding, it is useful to treat plants with the following biologically active substances: harmony, or sodium hydrohumate, or immunocytophyte.

Control measures for the Colorado potato beetle

To protect potatoes from the Colorado potato beetle, many gardeners dust bushes with wood ash, and also spray with infusions or decoctions of leaves, fruits or walnut shells, wormwood plants and its mixture with ash, tobacco, infusions of elecampane roots, dandelion and horsetail plants, onion peel.

You can also use biological control measures: bitobacillin, Colorado, or chemical ones: decis, intavir, fastak, sumialfa, karate, etc. All drugs are used according to the instructions.

How to get rid of the wireworm?


One of the most important measures in the fight against wireworm is getting rid of weeds. After harvesting cultivated plants, it is the root system of weeds in the soil that is their only source of nutrition. Even before planting potatoes, in order to get rid of the wireworm, you can set up traps: dig in large slices of potatoes tied to a wire to a depth of 5-7 cm, so that it is easier to remove these traps with worms that have penetrated into them after 2-3 days. And after the shoots of potatoes in the aisle, you can sow heaps of seeds of barley, oats or wheat. The wireworms like their young roots more, and then they will accumulate for a feast. When cereals grow 5-10 cm above the ground, these bushes are pulled out and thrown into boiling water. Worms entangled in the roots die.

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