Phytophthora: What To Treat, Preparations, Folk Remedies

Phytophthora is a genus of fungus-like microorganisms that cause phytophthorosis. More than 70 species of Phytophthora have been described by experts, but there are about 500 more varieties that have not yet been described. The name "phytophthora" is derived from two Greek words that translate to "plant" and "destroy". The disease most often affects plants belonging to the Solanaceae family: tomatoes, peppers, potatoes and eggplants.

Phytophthora (phytophthora)

Phytophthora: what to treat, preparations, folk remedies

The disease phytophthora (brown rot) usually appears in the second half of the summer.

It can destroy up to 70 percent of the potato and tomato crop. The simple fungus Phytophtora infestans is the causative agent of such a disease, it has the ability to multiply rapidly, for this reason it is called "infectious plant-eater". The lower leaf plates are often the first to be affected, but then the disease gradually spreads to the whole plant. If the air is very humid, brown spots appear on the leaves, covered from below with a white fluffy coating consisting of fungus spores. Strips of dark brown color appear on the affected shoots.

When air humidity increases, the spots and stripes begin to rot, but when the weather is dry, then they begin to dry out. Over time, the affected foliage becomes similar to a dry crust. On the surface of the skin of affected tubers appear rotting and decaying areas of dark color. And even stored tubers that look perfectly healthy may later begin to rot.

Phytophthora stains may also form on fruits, and they increase both in depth and width.

Both mature and green fruits get phytophthora. And if you picked perfectly healthy peppers and tomatoes from diseased bushes, they will still turn black with time.

Phytophthora control

Phytophthora: what to treat, preparations, folk remedies

Preventive measures

To prevent phytophthora from appearing on your plot, you must be sure to follow the preventive measures recommended by experts. Thus, preventive measures include preventive spraying of crops against Phytophthora with solutions of special preparations.

Main agronomic practices that will help protect the plot against Phytophthora:

  1. We recommend choosing varieties that are resistant to Phytophthora for cultivation.

  2. Remember the rules of crop rotation.
  3. Crop plants belonging to the Solanaceae family are not recommended to grow close to each other. For example, if the symptoms of Phytophthora are seen on potatoes, eggplants, peppers or tomatoes may already be infected after only one or two weeks.
  4. Potato plants should not be overgrown. Remember that the rapid spread of Phytophthora promotes poor ventilation and overcrowding.

  5. Also contribute to the development of the disease may sudden changes in temperature during the night and day. For this reason, experts recommend transplanting seedlings into the open soil only after all spring frosts have passed, or seedlings can be covered with something at night.
  6. Attempt to avoid a strong increase in the level of air humidity. For this purpose you may cover the area with a layer of mulch and not pour water directly on the plants when watering.
  7. Do not overfeed, and be particularly careful with nitrogen fertilisers.

  8. Gather the fruit after it has reached the ripeness stage. Never wait until the fruits are overripe.
  9. All foliage that grows below the fruits should be cut off, as should flowers that do not produce any ovaries.
  10. All fruits and bushes affected by Phytophthora are removed from the plot and must be destroyed by fire.
  11. In the beginning of the disease development it can be attempted to control it by traditional means that are time tested and safe both for humans and animals as well as for plants.

    However, if they are not effective enough, you will have to resort to the treatment of plants with fungicidal preparations that can be purchased in a specialized store.

The three best ways to control Phytophthora / Phytophthora prevention

Phytophthora pesticide treatment

Phytophthora: what to treat, preparations, folk remedies

To deal with this disease, sometimes crop protection measures alone are not enough and the grower must use pesticides. Many chemicals have been developed to combat the disease, but it must be remembered that Phytophthora can quickly become accustomed to them. To prevent this, plants are treated with different chemicals, alternating them.

The first time to prevent the plants should be sprayed in the spring, immediately after transplanting seedlings into the open ground.

Most experts advise to correlate the terms of subsequent spraying of crops against phytophthora with the growth of common fungi in the forest: you must treat fungal diseases at the time when forest fungi start growing, even if there are no signs of phytophthora development on the plants. The bushes are sprayed in the morning and before noon, choosing a sunny, dry and windless day.

Soil treatment

Microbiological preparations and fungicides are used to clean the soil from Phytophthora spores. For prevention purposes, fungicides are applied to the soil in early spring, at least four weeks before planting potatoes or seedlings in the open ground. As for microbiological agents, they can be applied to the soil whenever you want during the whole vegetation period, except during flowering, because this preparation can harm bees.

Copper-containing chemicals are quite effective against Phytophthora, such as copper sulfate, Bordeaux liquid, Phytosporin-M, Trichodermin and Ordan. For example, a solution of copper sulfate (2-3%) can be used to treat the soil, after which the site is recultivated. Then the soil is poured with a solution of Phytosporin (1 tbsp. of the product per bucket of water), and per 1 square meter of land should take 10 liters of mixture. Those plots intended for cultivation of strawberries and flowers are poured with Ordan or Alirin solution; the same agents can also be used for preventive spraying of grapes.

The greenhouse is treated against this disease in autumn and early spring by burning special sulfur balls in it. During processing, never forget the safety rules and stay away from the smoke emitted by the tacks.

Phytophthora on tomatoes: how to fight

Phytophthora: what to treat, preparations, folk remedies

Preventive measures

Many gardeners prefer not to let phytophthora develop on tomatoes, resorting to agronomic techniques, than then long and strenuous fight against this disease. It should be taken into account that it is very difficult to get rid of phytophthora definitively.

  • Before planting seedlings the ground on the plot shall be treated against Phytophthora;
  • When planting seedlings the plot surface shall be covered with a layer of mulch;
  • Time cut off stems and lower leaf plates;
  • Specialists suggest planting peas, corn or curly beans around the perimeter of tomato plot.

So soon as the seedlings are transplanted into the open ground, they should be sprayed with Trichodermin or Phytosporin-M solution for prevention.

Phytophthora control on seedlings

Phytophthora: what to treat, preparations, folk remedies

If tomato seedlings have been affected by phytophthora, then it is recommended to remove all diseased bushes and then water the soil mixture with Phytosporin-M solution. You can also unpack the seedlings into individual cups, using fresh sterilized soil mixture, which is poured with Phytosporin. The same tool is used to treat the soil on the plot, which will be planted tomatoes. Remember that after the treatment of soil on the bed with fungicidal agent should take at least 30 days, only then can you plant tomatoes in it.

If you do not have that much time, then it is better to use Alirin to treat the soil on the plot.

Tomato treatment

Phytophthora: what to treat, preparations, folk remedies

If it rains often in summer, then to cure the phytophthora affected tomatoes, treat them at least 4 or 5 times at intervals of 1-1.5 weeks. The last spraying with phytophthora pesticides should be done at least 20 days before harvesting. To increase tomatoes' resistance to the disease and strengthen their immunity, they are treated with the growth regulator Oxygumat (100 milligrams per bucket of water) or Exiol (1 milligram per 3 liters of water).

Phytophthora can affect both those plants growing in the open ground and those growing in the greenhouse. If tomatoes grown indoors are affected, the grower can lose almost the entire crop. To combat this disease in the greenhouse, the same chemicals are used as in the treatment of bushes in the open ground. However, do not neglect the safety rules under any circumstances, because in the greenhouse it is much easier to get poisoned by toxic chemicals than when treating tomatoes in the open ground.

Remember that the treatment against Phytophthora should be all bushes at once, because a single treatment will be ineffective.

In general it is not possible to control this disease completely and all treatments only suppress its development.

Phytophthora on tomato plants is enemy number 1. ]

Phytophthora preparations

Phytophthora: what to treat, preparations, folk remedies

Phytophthora on tomatoes is treated with such products as: Bordeaux mixture, Ridomil Gold, Tatu, Quadris, Baikal EM and Shine. Before preparing a treatment solution, it is necessary to be sure to study the manufacturer's instructions, which are available on the package. To suppress the disease on bushes, you can only carry out several treatments with a break of 1-1.

5 weeks. Remember that pathogens quickly get used to the drugs, so do not forget to alternate them. Try to use a more powerful product for each subsequent treatment than the previous one.

Phytofluorosis on potatoes

Phytophthora: what to treat, preparations, folk remedies

Phytofluorosis treatment

The symptoms of tomato and potato phytofluorosis are very similar: spots form on the leaves which spread rapidly throughout the bush, as the disease develops the leaf plates curl and dry out. If the disease affects the tubers, then hard spots can be found on their surface.

In order to prevent the development of the disease, the following bush treatment scheme should be followed:

  1. The first treatment with a systemic fungicide preparation is made after the height of the tops is 25-30 centimeters. Potatoes can be sprayed with the following preparations: copper sulfate (0.2 gm per 1 L of water), Bordeaux liquid (1%) or copper sulfate (2 gm per 1 L of water).
  2. So long before flowering the bushes must be sprayed with Oxygumat, Epin or Axiol. But if weather conditions are unfavorable for phytophthora development, then treat plants only with a resistance inducer, e.

    g. Krezacin or Silk: 1-2 weeks later bushes are sprayed with a contact fungicide such as Ditan M-45 or Efal, and you can also use copper oxychloride (strictly follow the manufacturer's instructions), for preventive treatment the dosage is reduced by 2 times. If potatoes are affected very much, then they are sprayed with Ridomil MC, Oksihom or Ridomil Gold MC, and 1.5-2 weeks later they are sprayed again with the same preparations. When the bushes have finished flowering, they can be sprayed with Bravo solution, and the treatment is repeated one to one and a half weeks later.

  3. Allufit is recommended for phytophthora treatment during tuber ripening.

The treatment is best done on a cloudy, but dry and windless day. If it rains after spraying, the bushes will have to be treated again. The haulm should be sprayed until it has completely withered away.

Preventive measures

Phytophthora: what to treat, preparations, folk remedies

To protect potatoes from phytophthora, you must choose the most suitable place to plant them, and it is best to use those varieties that are most resistant to this disease for cultivation.

Also do not forget to treat plants in time in order to prevent it. It is recommended to grow this culture on level plots. If you choose a low-lying or humid area, it can cause fungal diseases. The soil should be light and well drained, and the area should be well lit and with a good breeze. If possible, choose a site that is away from other plants of the Solanaceae family.

Potatoes will grow best in areas where perennial grasses, beets, winter crops, corn, and flax were previously grown. And the worst predecessors of this plant are nightshades. After peppers, potatoes, tomatoes and eggplants can be grown again in the same area only after 4-6 years. If you do not have the opportunity to adhere to full crop rotation, then it is recommended to grow potatoes on a plot at least once every 2 years, with the interval it is sown in mustard or radish, which must be mowed and buried in the ground. Thanks to radish and mustard, the risk of potatoes being affected by phytophthora or other fungal diseases is reduced by 3 times.

Before planting, it is recommended to treat the soil on the plot (how to do this is described in detail above). Also experts recommend to use only absolutely healthy planting material for cultivation. In order to understand which tubers are affected by phytophthora, it is recommended to keep them for 15 days at a temperature of 15 to 18 degrees. As soon as it is clear which tubers are diseased, they must be removed and the remaining planting material treated with Fytosporin-M or Agat-25K.

Phytophthora on CARTOFLE WHAT TO DO?

Pre-planting treatment

To avoid having to worry about whether or not your potatoes will get phytophthora, it is recommended to choose varieties resistant to this disease such as Lazarus, Arina, Rosara, Viza, Verb, etc.

. Also for preventive purposes, phosphate and potash fertilizers are added to the soil before or during planting. And after the formed tubers begin to gain weight, increase the potassium component by 1.5 times. If there is too much nitrogen in the soil, it will cause delay in tuber development, resulting in increased susceptibility to phytophthora.

After the set of mass by tubers will be completed, the surface of the soil shall be loosened, and the haulm shall be mowed, thus accelerating the process of building up the density of the rind by tubers. And also help it will be able to treat the soil on the plot with a solution of means Reglon Super. And also remember to dig out and destroy diseased plants in good time, remove weeds from the area, and do not water bushes by sprinkling if the weather is cool and dry.

Phytophthora disease in different crops

Phytophthora: what to treat, preparations, folk remedies

That has been explained in detail above about how to deal with phytophthora disease in tomatoes and potatoes. However, this disease can also affect other plants.

Peppers and eggplants are also susceptible to Phytophthora solanensis. Symptoms of the disease on these crops are similar to those observed when potatoes or tomatoes are infected with phytophthora. And preventive measures and ways to combat the disease in this case are the same as those used for tomatoes. But for the treatment of phytophthorosis of eggplants, experts advise, use such means as: Anthrakol, Consento or Quadris. When seedlings are transplanted into the open ground after 8-10 days, their first spraying with Quadris or Anthracol is carried out.

Then regularly every 12-14 days, repeat treatments, and fungicidal drugs must be alternated, otherwise fungi can get used to them. Peppers affected by phytophthora is recommended to spray with Barrier, Oksihom or other fungicides. The main thing to remember is that the bushes twice or three times in a row can not be sprayed with the same product. In some cases, cucumbers grown indoors may be affected by Phytophthora, but these can only be treated with folk remedies (more about them below).

Phytophthora preparations

Phytophthora: what to treat, preparations, folk remedies

Fitosporin-M, Trichodermin and Alirin are the pesticides most commonly used by gardeners to control phytophthora:

  1. Phytosporin-M, Trichodermin and Alin.

    These are broad-spectrum microbial fungicides that are based on natural bacterial culture.

  2. Antrakol, Bordeaux liquid and Copper sulfate. These broad-spectrum contact fungicides are very effective.
  3. Quadris and Bravo. These systemic fungicidal preparations are used for both greenhouse and outdoor crops.

    They have curative, protective and eradicating effects.

  4. Ridomil Gold, Tatu, Oxychom and Ordan. These are fungicidal agents of contact and systemic action.
  5. Baikal EM. This biofertilizer helps to speed up bush growth and fruit ripening.


Native Phytophthora Treatments

Many gardeners today try to avoid using pesticides on their plots if possible. If the disease has just begun to develop, it is quite possible to try to cope with it by folk remedies. The folk remedies that are most popular with gardeners are described below.

Copper wire

Phytophthora: what to treat, preparations, folk remedies

This method using copper wire was patented by German scientists. It consists of wrapping the root system of the seedlings with a thin copper wire before planting them in the open ground.

There is another method of using copper wire to prevent fungal diseases. In this case, the stem of pepper, eggplant or tomato is pierced with copper wire (length 30 to 40 mm). Next, the wire is pushed through the stem, and then its tips are put down and pressed against the plant. In this case, the culture constantly receives microdoses of copper, which helps to stimulate its respiration, stabilize chlorophyll production and enhance oxidative processes. Thanks to this, the plant's resistance to fungal diseases increases.

Remember that you can only flare the stem with the wire when it is hardened. Do not forget to prepare the copper wire by annealing it and sanding it down. Then it is cut into small pieces and inserted into the stem of the bush at a height of about 10 centimeters from the surface of the soil. The tips of the wire should not be wrapped around the stem.


Phytophthora: what to treat, preparations, folk remedies

The fact that iodine has antimicrobial properties has been known for a very long time.

It has long been used to protect the leaves of potatoes, eggplants, tomatoes and peppers. From Phytophthora iodine is used as follows: a bucket of water is combined with 1 liter of nonfat milk and 20 drops of iodine, all mixed well. Seedlings are treated with this mixture half a month after transplanting them into the open ground, and then the plants are sprayed with it regularly once a week.


Phytophthora: what to treat, preparations, folk remedies

Milk whey, which is combined with water in a 1:1 ratio, is quite effective in phytophthora control. A thin film appears on the surface of the plant sprayed with this mixture, which does not allow pathogenic fungi to penetrate inside the bush.

Microflora, which is contained in the serum, is destructive to the pathogen phytophthora. However, the film formed after the treatment is destroyed very quickly, so you should spray the bushes systematically. The first whey spraying is done in July and then it is repeated every day.

SYROWS and IOD against Phytophthora and powdery mildew on: tomatoes and cucumbers. Milk whey for the vegetable garden.


Bucket of water combined with 1 liter of kefir (fermented for 2 days) or yogurt, treat the bushes with the mixture. The first spraying with this mixture can be done 15 days after replanting the seedlings on the bed.


Salt solution is also quite effective in controlling Phytophthora. It forms a film on fruits, leaves and shoots that does not allow the pathogens to enter the plant through the stomas. But such a solution is used only to protect plants from Phytophthora, not to treat them.


Garlic has a detrimental effect on the fungus spores. The first garlic treatment is done shortly before the formation of ovaries, then it is repeated twice: 1.5 weeks later and half a month after the second spraying. For the infusion pour 1.5 tbsp garlic pulp (finely chopped heads and stems) in a bucket of water, after 24 hours, strain the product and combine with 1.

5-2 grams of manganese potassium. Stir well and you can then spray the plants.

Wood ashes

Phytophthora: what to treat, preparations, folk remedies

A bucket of water and 5 liters of wood ashes, the infusion is ready after three days, but don't forget to stir it up occasionally. Drain the infusion carefully and add to it such an amount of water that the final volume is equal to 30 liters. Add to the solution 35 grams of grated laundry soap or liquid soap, mix everything thoroughly.

The plants are treated with this solution 3 times during the season: a week and a half after transplanting seedlings to the bed, shortly before flowering and just after the beginning of the first ovaries.

Strawberry fungus

Regularly 1 time in 1.5 weeks in early morning in windless and quiet weather spray the bushes with a composition that can control phytophthorosis development. To prepare it, 100 grams of fresh mushroom mushroom is crushed, dried, and then put through a meat grinder. After that, it is combined with 1 liter of boiling water, the container is covered with a lid and wait until the mixture cools completely.

The strained infusion is sprayed on the bushes for the first time during the appearance of ovaries, and the treatment is repeated half a month later.

Native remedies for phytophthora on tomatoes. Treatment of tomatoes with milk whey.


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