How to save an orchid with a rotten heart
The article answers netizens' questions on how to save an orchid with a rotten heart and provides you with simple and effective rescue measures. Let's take a look together.
In the late spring and early summer season, with bright sunshine and suitable temperatures, it is the time when new orchid seedlings emerge from the pot and grow leaves, and their growth is particularly vigorous. However, this period is also when bacteria and pests multiply, making the prevention of new orchid seedlings' rotten hearts especially important. So, what are the causes of the rotting of the new leaves' hearts in orchids and how to prevent it? Let's talk about this topic today.
Generally speaking, the rotting of new orchid seedlings' hearts is mostly caused by black rot, with the pathogen being mainly pythium or viral bacteria. The causes of the disease and the preventive measures mainly include the following five aspects.
1. Improper watering. After the new orchid seedlings emerge from the pot and spread their leaves, improper watering methods during the watering process, such as pouring water directly from above the new leaves, can cause water to accumulate in the leaf hearts for too long. Combined with poor environmental ventilation, it can easily lead to yellowing and rotting of the new leaves. Therefore, when the new seedlings are spreading their leaves, one must be careful with watering, trying to water from the edges of the pot or use the immersion method, avoiding direct spraying on the new leaves to prevent water accumulation in the leaf hearts and allowing pathogens to take advantage and cause rot.
2. Poor ventilation in the growing space. In the late spring and early summer, as temperatures rise every day, proper ventilation in the orchid-growing environment is a must. If the growing environment is too stuffy, combined with high temperatures and humidity, and poor ventilation, it can cause the base of the new seedlings to become闷 and unventilated, easily leading to fungal infections and resulting in rotting in the leaf hearts. Therefore, during daily maintenance, special attention should be paid to the ventilation of the seedlings' growing environment, often opening windows for ventilation to maintain the exchange of air inside and outside the space. The relative humidity should be kept at around 70-80%, and the matrix for growing seedlings must be loose and breathable. The base of the new seedlings should not be buried too deep, with the rhizome slightly exposed above the planting material.
3. Diseases and pests causing lesions. In early summer, pests harmful to the growth of orchid seedlings can become rampant. It is essential to prevent the invasion of pests such as scale insects, spider mites, aphids, snails, and slugs. These pests like to absorb the sap of new seedlings, and after they bite the leaf hearts, the new seedlings are easily infected with pythium, leading to the rotting of the leaf hearts. Therefore, it is necessary to spray insecticides and fungicides such as quinalphos, omethoate, methyl thiophanate, cupric hydroxide, and methyl topricide every 10 to 15 days, alternating the drugs and repeating the spraying. Generally, after 2 to 3 rounds of spraying and disinfection, the condition can be cured. For other uninfected seedlings, regular spraying of preventive drugs is also necessary.
4. Damage from excessive medication and fertilization. When maintaining orchid seedlings, the excessive use of hormones or over-dosage of inorganic fertilizers like orchid bacteria king can cause the imbalance of the essential nutrients nitrogen, phosphorus, and potassium needed for orchid growth, leading to a deficiency of trace elements, excessive growth of new seedlings, and weak leaf stalks. Some symptoms may include burning the base of the leaves, and in severe cases, the leaf heart may show tissue necrosis and turn brownish-black. Therefore, one must never rush the growth of new seedlings and ignore the damage from fertilizers and medications. It is essential to use medications according to standard requirements and provide a dilute nutrient solution only when ensuring robust growth of the seedlings, avoiding the opposite effect of helping the seedlings grow too quickly.
5. External stimulation to the seedlings. The leaf hearts of new orchid seedlings are very delicate, and any slight carelessness can cause external stimulation and fungal infection. For example, when watering the seedlings, if the water temperature differs greatly from the temperature of the pot surface, sudden watering can easily cause the leaf hearts to be stimulated and become uncomfortable, or even cause burns to the new buds, making it easy for the leaves to be eroded by pythium. Therefore, the water used to water orchids should be placed next to the pot for a while to allow the water temperature to approach that of the pot surface before watering. In hot weather, it is best to water before 9 am and after 5 pm, avoiding direct watering with tap water at high temperatures, as this can easily cause rotting.
The above shares the introduction on how to save an orchid with a rotten heart and provides you with simple and effective rescue measures for everyone to learn and understand!