What Causes the Black Tips on Orchid Leaves
You may not be aware of the reasons behind black tips on orchid leaves or the solutions to this problem, which falls under the category of plant care. Let's explore this together.
Blackened leaf tips are a common issue encountered during orchid cultivation. The symptoms include the blackening of the leaf tips, followed by a gradual whitening and withering, with a yellow transition zone at the boundary between black and green. Black tips usually do not lead to the death of the orchid but can affect its appearance. A once vibrant green leaf with irreversible black tips can be unsettling. If black tips are not addressed, the entire leaf can wither, and even the health of the whole orchid plant can be affected. The main causes of black tips on orchid leaves are primarily due to the following factors.
I. Excessive Dryness
Many orchid growers are afraid of waterlogging in the roots and therefore strictly control the watering frequency, not daring to water the orchids excessively. However, this is incorrect. Long-term dehydration causes the plant to appear瘦小 (small and thin), with dull leaves, where transpiration exceeds absorption, leading to black tips in less severe cases and dehydration and wilting in severe cases.
Solution: Pay attention to maintaining the humidity in the pot, avoiding excessive dryness. Do not wait for the potting mix to completely dry out before watering. Water when there is still some moisture in the pot, and make sure to water thoroughly each time, avoiding watering only halfway.
II. Low Humidity
Part of the moisture in orchid leaves is obtained from the roots, and another part is absorbed from the air. Excessively dry air can cause an imbalance in the moisture supply and demand of the leaves. Since the leaf tips are farthest from the roots, they will be the first to lack water and wither, leading to black tips on the orchid leaves. Generally, outdoor air has higher humidity with dew in the morning and evening, making black tips less likely. Indoor air, on the other hand, tends to be much drier, making black tips more common. This is why orchids in our homes are prone to black tips.
What Causes the Black Tips on Orchid Leaves
Solution: Enhance the humidity around the location where the orchid is placed, ideally keeping it between 60-90%. Humidity below 30% can easily cause black tips. We can mist and spray the leaves of the orchid, doing so in the early morning or at night during summer, and in the morning during winter, or use a humidifier to increase humidity.
Caution: Placing a water-filled saucer under the pot does not solve the humidity issue because the area of the saucer is too small to compensate for the dryness of the air.
III. Excessive Ventilation
Orchids require a ventilated and shady environment but not excessive ventilation. Wind can carry away moisture, and the faster the wind speed, the quicker the water loss. If the location where the orchid is placed has too strong wind, the leaves will also experience an imbalance in moisture, similar to the black tips caused by dry air.
Solution: Good ventilation does not necessarily mean good ventilation inside the pot. Therefore, we should consider the ventilation inside the pot by using breathable granular potting mix. It is enough to place the orchid in an environment where the air can circulate and the leaves can gently sway, avoiding placing it in a drafty area.