Why do petunia leaves turn yellow?
Content:
One of the most common summer flowers is petunia. In order for the plant to delight with its flowering and splendor for a long time, many gardeners pay considerable attention to it. Often, when growing a flower, you can see yellow leaves on the stem.
About petunia
The flower is native to South America. Petunia has its own specific characteristics in terms of planting:
- Adequate amount of sun. Partial shade is best;
- The air should have a temperature regime of about 25 ̊С;
- The soil for planting should be used fertile, it must first be fed. The most important thing is not to overdo it with organic fertilizers;
- The plant is constantly moistened with warm water.
The flower does not like a lot of moisture in the soil and in the atmosphere. Also, petunia does not tolerate frost well.
If you do not take these recommendations into account, then the flower will have yellow leaves, rot, the flowers will look dull. Seedling material of the plant does not tolerate excessive watering, poor sunlight and low temperatures. Because of this, the leaves turn pale, turn yellow, or fall off. An adult plant is actively involved in flowering, and as a result, it lacks nutrients, which leads to disease and pest damage.
Why does foliage turn yellow
The main reason for yellowing and drying of leaves is an excess of moisture. If the soil is highly moistened, then the root system does not have enough oxygen, nutritional disruptions appear, the leaves become yellowed. First, the lower foliage turns yellow, then the yellowness goes to the top. At the same time, the stem of the plant may begin to rot.
How to identify excessive moisture
If the petunia is in a building and the air in it is excessively humid, then the foliage will turn yellow evenly over the entire surface.
To save petunia, you need to transplant the plant into new soil, change the planting pot or flowerpot, and make drainage.
The root system is treated with charcoal or disinfected with Fitosporin.
If the plant gets a small amount of nutrients, or they come unevenly, then this can lead to the fact that the petunia stops blooming.
With pallor or yellowness of substances, you can immediately determine that there is not enough nitrogenous compounds, while a characteristic feature is that yellowness appears from the bottom of the bush.
If the plant lacks iron, then the leaf itself remains green, and the distance between the veins changes color.
With a lack of magnesium, petunia leaves begin to turn yellow and curl.
When planted in a closed plant, the plant is susceptible to a lack of nutrients, such petunias need to be fed regularly for normal growth. During the growing season, once every 14 days, the plant needs to be fed with fertilizer complexes, for example, the following:
- Agricola;
- Bona;
- Pocon;
- Fertika.
Agrotechnical problems can lead to the fact that:
- The foliage of the plant will begin to turn pale or yellow;
- Petunia will thicken, which will lead to a lack of oxygen, nutrients and light;
- The acidity of the soil will increase.
In order for the plant to grow well, you need to clearly and carefully follow the various recommendations for planting and care, and it is equally important to follow the planting scheme correctly.
From the table you can see the main causes of ailments in the plant..
Changes that have occurred | Why happened |
Dryness and yellowing of leaves | Low humidity, high temperature, dry air |
The foliage began to wither and turn yellow | Excessive soil moisture. Whitefly damage |
Yellowing of the upper foliage | Chlorosis damage |
The edges of the leaf turned yellow | Decrease in air temperature, excess moisture |
Yellow streaks | Lack of nutrients |
The foliage is sticky and yellow | Damage to aphids or mealy sundew |
Yellowing of the lower foliage | Excessive moisture, high soil density, lack of nitrogenous compounds |
Several reasons can harm the plant at the same time.
Pests are fairly constant in attacking plants that are lacking in nutrients or poorly cared for.
Diseases and enemies of petunia
Chlorosis. The disease can be distinguished by the yellowness of the veins on the top of the plant. The disease attacks the plant with a lack of glands in the soil. If the symptom is not eliminated in time, then the petunia will turn yellow completely. To save the plant, it is sprayed with Ferrovit for a couple of days. The yellowing should go away in about a month. To petunia does not suffer from this ailment, you need to feed the plant with special mineral fertilizer complexes.
Powdery sundew... The disease can be identified by the yellowness of the foliage and the appearance of a gray coating on the inside of the leaf. The fungus actively multiplies at cold temperatures and excessive moisture. To cure a plant, you need to use products that include copper or its compounds. The most common drugs are: Fundazol, Bordeaux solution, Alirin-B.
First you need to remove the damaged areas of the flower, after the petunia you need to spray with a solution of the product.
Insects. Plants that are planted in unprotected soil are often affected. The most evil enemies are considered: whitefly, spider mites, aphids. A frequent occurrence is a spider mite, which likes to settle in greenhouse conditions, it develops especially favorably in low air humidity - less than 50%.
Tobacco mosaic. Yellowish spots appear on the sheets. Petunias that have been affected by the disease must be removed from the site. Affected flowers should not be thrown in the compost heap.
Small insects absorb petunia juice, foliage loses its strength and turns yellow. To understand that the plant was attacked by a tick, you need to look closely at the upper plants, they will be entangled with a small amount of cobwebs. To destroy the pest, you need to raise the humidity level in the greenhouse to 75%, and spray the plant with Fitoverm.
The whitefly does not harm the plant itself, but its offspring adhere to the stem at the base of the leaf and absorb the petunia sap. The plant begins to turn yellow and wither. To defeat the pest, you need to apply Permethrin or Spark.
Aphids are considered one of the dangerous pests, since they can do great harm to the plant in a short period of time. Small pests of pale green color accumulate in heaps on the shoots and foliage of young plants and gradually absorb the juice. In addition to the fact that the pest destroys petunia, it is also capable of infecting the plant with some kind of virus or fungus.
You can defeat aphids with improvised means:
- Soap solution. You need to dissolve 50 g of laundry or green soap in 10 liters of liquid.
- Infusion of tobacco. 60 g of tobacco is added to 10 liters of liquid.
If the plant is badly damaged, then Fitoverm, Aktar, Confidor can be used.
What is the difference between the appearance of yellowness indoors or outdoors?
Petunias that are planted in open soil are less damaged by excess or lack of moisture, lack of nutrients.
A plant, if not getting enough food, can get it on its own in an open environment than if it grows in a pot. For example, if petunia is suffering from drought and lack of nutrition, then the root system will gradually deepen downward.
But despite all the advantages, there is a significant disadvantage, flowers growing in the garden often suffer from the harmful effects of insects that jump from bush to bush.
A plant that is planted in pots or pots needs to be regularly supplied with fertilizers and watering. Here, a significant role is given by the care of the owner, who will be responsible for the health of his offspring.