What to Do About Grapes with Yellow Leaves
The editor explains how to deal with yellow leaves on grapes and introduces the reasons and solutions for this issue in the field of green plants and flowers. Let's continue with the introduction by our site's editor.
Poet Tang Yanshan of the Tang Dynasty praised grapes with the lines, "The bead curtain is not rolled up at night, and the bright moon falls into the clear shadow," referring to the round and cute appearance of grapes, like treasures. Grapes are a common fruit in life, but don't underestimate them. Grapes are one of the oldest fruit tree species in the world. Grapes have a wide range of uses, not only eaten directly but also made into many other foods, such as wine, raisins, and grape juice, all of which are loved by people. It is evident that the economic benefits of planting grapes are also considerable. However, during the planting process, the issue of yellow leaves on grapes often arises, which can lead to unhealthy growth of the plants and a decrease in fruit yield, affecting the interests of the growers. So what causes this, and how should it be dealt with? Let's take a look together.
I. Deficiency of Elements in Grapes
When fertilization is unbalanced, there is a high dependency on nitrogen fertilizer, and the supply of other nutrients is ignored, leading to a deficiency of trace elements such as iron, magnesium, potassium, and boron in grapes. This can result in antagonistic effects between elements, affecting the plant's absorption of nutrients and also polluting the soil, causing the leaves to turn yellow and appear unhealthy.
Solution: Fertilize rationally and pay attention to supplementing trace elements for the plants. Whether it's organic or inorganic fertilizer, chemical or microbial fertilizer, they should be used in a balanced combination to ensure comprehensive nutrition for the plants.
II. Improper Management
1. After harvesting, neglecting the management of water and fertilizer can lead to soil compaction, nutrient loss, or improper watering, resulting in reduced nutrient accumulation in the plants, insufficient or excessive water, which can affect the development of new shoots and make it difficult for plants to overwinter, causing leaves to turn yellow the following year.
2. Improper arrangement of the orchard trellises or failure to prune grapes in time can lead to insufficient light for the plants, insufficient photosynthesis, and yellow leaves.
3. Neglecting pest control after harvesting can lead to early defoliation along with the phenomenon of excessive growth of new shoots, insufficient nutrient accumulation in the plants, difficulty in overwintering, withering and death of the roots, and yellow leaves.
Solution:
1. Strengthen the management of water and fertilizer, apply organic fertilizer, water moderately and appropriately, and regularly loosen the soil for the plants.
2. Reasonably layout the orchard trellises and prune grape branches and leaves in time.
3. Pay attention to pest control after harvesting to keep the leaves intact.
4. In spring, most of the absorbing roots of grapes have died, so it's necessary to spray foliar fertilizer on grapes. You can use 0.2% to 0.3% ferrous sulfate combined with 0.3% urea or 500 times of multi-effect fertilizer, applying once every 7 to 10 days, for a total of 3 to 4 times.
III. Pesticide Damage
When preventing and controlling pests or weeding, pesticides are usually sprayed. However, if used improperly, the damage caused by pesticides to grapes can lead to yellowing and falling leaves, reducing yield, and in severe cases, even plant death.
Solution: After spraying pesticides on the plants, inspect the orchard. If abnormal conditions are found in the plants, dilute the pesticide by watering the plants immediately. If it's a herbicide or other chemicals sprayed on the ground, use a lot of water to remove the pesticide residue.
IV. Fertilizer Damage
Improper application of fertilizer can also cause the leaves of the plant to turn yellow. Fertilizer damage usually manifests on the leaf surface of the plant and sometimes on the roots and new shoots. Excessive application of fertilizer, high fertilizer concentration, and incompatible fertilizer properties can harm the plants, leading to poor growth of new shoots, yellowing of young leaves, and in severe cases, withering and death of leaves or new shoots.
Solution: Before applying fertilizer, confirm that the properties of different fertilizers are compatible, control the concentration and amount of fertilizer, and avoid direct contact with the roots. After fertilizer damage occurs, immediately dig out the excess fertilizer, water heavily to dilute, and perform tillage to loosen the soil, improving the root environment.
V. Disease
When grapes are affected by yellow leaf disease, the leaves will turn yellow.
1. Symptoms
In the early stage, young leaves appear yellow-green or yellow-white, then the edges of the leaves become scorched, plant growth and development are affected, the fruit turns yellow and stops growing, and some will fall off.
2. Causes of the Disease
(1) Iron deficiency. Breeding in saline-alkaline soil can lead to an imbalance in the plant's physiological state, preventing the absorption and transfer of iron, causing the plant to become ill.
(2) Under high temperatures, the plant requires a lot of nutrients to support its growth. If the water temperature for irrigation is too low, the increase in ground temperature is slow, and the soil is compacted, leading to a decrease in the plant's root respiration and nutrient absorption ability, causing the disease.
3. Incidence Pattern
It often occurs in May, and the situation can be cured within 7 to 10 days with timely treatment.
Solution:
1. If it's a new grape garden, pay attention to trenching and watering before formal planting to reduce soil salinity.
2. After grapes have been harvested, every two years, apply decomposed organic fertilizer in the late autumn, before grapes prepare to overwinter.
3. During the growing period of grapes, apply compound fertilizer containing multiple elements.
4. In the early stage of the disease, spray 0.5% ferrous sulfate solution on the leaves for treatment.
The above is the specific content of what to do about yellow leaves on grapes and the reasons and solutions for yellow leaves. If it can be of help to you, remember to visit our website often!