What causes orchid leaves to turn yellow and dry?

The leaves of an orchid are its most sensitive and fragile part and can be easily affected by many factors. Excessive sunlight exposure, inappropriate humidity, extreme temperatures, poor ventilation, high drug concentrations, viral attacks, and natural aging of the plant can all cause orchid leaves to turn yellow and dry. The condition of the leaf tips can largely serve as an indicator of the health of the orchid. In short, the yellowing and drying of leaves can be seen as a "barometer" of the health of orchids. Let’s learn in detail why orchid leaves turn yellow and dry.

Reason 1: Root problem

Drying and scorching of orchid leaf tips is often a sign of root problems. Overly wet or long-term damp soil and poor ventilation may cause root rot. Orchids with root rot usually have yellowing and blackening of the leaf bases, and then yellowing and dry leaf tips. If the tips of many leaves turn black and the base of new leaves turn yellow, it can basically be judged as root rot.

The treatment method is to take out the orchid seedlings, cut off the rotten parts, soak them in fungicide and dry them, use wood ash or sulfur powder to disinfect the cut ends, replant them after the cut ends shrink, and replace them with planting materials with good air permeability.

Reason 2: Bacterial infection

Before infection by the bacteria, spots often appear first, gradually extending to the tips of the leaves, which first turn yellow and then black and wither. For minor infections, cut off the diseased leaf tips and spray with antibiotics. Severe infection requires root pruning, the same method as treating root rot.

Reason 3: Dry air

The relative humidity of air suitable for orchid growth is 70%-85%, and the minimum should not be lower than 55%. Too dry air or strong winds can cause leaf tips to burn. The solution is to spray water into the air frequently or place basins of water around the flower pots to increase humidity.

Reason 4: Root touching the pelvic floor

Orchids that have not had their soil changed for many years and are growing vigorously may have their roots touching the pot wall, and high temperatures may cause the leaf tips to burn. The method of identification is that the black part of the leaf tip is only at the tip of the leaf and does not spread to the center. The solution is to avoid exposure to the sun and change to a larger pot in time.

Reason 5: Normal update and replacement

Orchid leaves have a lifespan and usually die naturally after 4-5 years. Normally, yellow leaves start from the tip of the base leaf and turn yellow from top to bottom. Other orchid seedlings or leaves are normal. This is a natural phenomenon and there is no need to worry too much.

Reason 6: Fertilizer or medicine is too concentrated

Excessive fertilization or use of pesticides can also cause leaf tips to burn. The leaf tips of orchid seedlings that were damaged by fertilizer became burnt and black spots appeared on the leaf surface. The leaf surfaces of orchid seedlings that were damaged by medicine developed irregular yellow spots that gradually turned brown. The treatment method is to water to dilute the concentration of medicine or fertilizer in the pot, and then spray or water the next day to prevent the fertilizer from being too concentrated.

The above are some common reasons why orchid leaves turn yellow and dry. In fact, the yellowing and drying of orchid leaves is a common problem. The key is to find the cause and take corresponding measures. Proper maintenance and careful care can avoid or solve this problem.