How to care for potted orchids
Are you curious about how to care for potted orchids, as well as the planting methods and precautions for orchid cultivation? Next, the editor will introduce the information for netizens.
Orchids have a profound cultural heritage, and many scholars and literati have left behind numerous poems in praise of them throughout history. "Plum, orchid, bamboo, chrysanthemum" are known as the "four gentlemen of flowers," and orchids are also one of the top ten famous flowers in China. Based on years of practical experience in orchid care, the author has summarized a set of orchid potting and maintenance techniques for reference by orchid enthusiasts.
1 Requirements for water, temperature, light, humidity, wind, and planting materials
1.1 Requirements for water
Water Orchid stems are pseudobulbs, and the roots are fleshy. Their rootstocks can store some nutrients and water, and their leaves are corneous. Due to these characteristics, orchids are relatively drought-resistant. During planting, avoid积水 in the orchid pots, as it can affect the root respiration and easily lead to root rot.
1.2 Requirements for temperature
Whether orchids can grow normally is closely related to temperature, but different varieties require different optimal growth temperatures. For example, the optimal growth temperature for Cymbidium is 28-30°C, while for Cymbidium sinense, it is 25-28°C.
1.3 Requirements for light
There is a saying about flowers: "Shaded rhododendron, sunny peach blossoms, semi-shaded and semi-sunny orchids." It is evident that orchids require semi-shaded and semi-sunny lighting conditions. Most national orchid varieties need 70%-90% shading, and can be exposed to more sunlight before Qingming and after the autumn wind. When the light is too strong, the leaves turn yellow, and the leaf tips wither; when the light is too weak, the growth is poor, and the flower buds are few or do not bloom.
1.4 Requirements for air humidity and ventilation conditions
Orchids prefer to grow in a well-ventilated environment with high air humidity, but the ventilation should be moderate, otherwise the leaves can be easily damaged. To increase the air humidity in the orchid greenhouse, regularly spray water around the orchid ground. During the growing season, the relative humidity should be 70%-85%, and it can be reduced to 40%-50% in winter.
1.5 Requirements for planting materials
Planting materials are the matrix for orchid growth. The basic requirements are good water permeability and aeration, general organic matter content, no pollution, slightly acidic to neutral pH (5.5-6.5), and certain fertilization and water retention capabilities. There are many methods for configuring orchid cultivation materials, mainly using the following two methods: The first is 60% decomposed leaf soil, 30% red soil, and 10% river sand; the second is 40% decomposed leaf soil, 30% red soil, 10% river sand, and 20% white fungus residue. Orchids grown with these two formulas have good growth.
2 Cultivation and maintenance techniques
2.1 Choosing an orchid pot
Choosing a suitable orchid pot is one of the important aspects of successfully growing orchids. There are many types of orchid pots, including clay pots, purple sand pots, plastic pots, ceramic pots, and glazed pots. Although clay pots are not aesthetically pleasing, they have good breathability, quick water evaporation, can timely adjust the moisture of the planting materials, are unlikely to cause root rot, and are inexpensive. Therefore, clay pots are currently the most commonly used. There are many styles of orchid pots, and according to experience, the cylindrical shape is the best. The ratio of pot height to diameter is about 1.4:1, and the size should be 2 fingers (about 3 cm) larger than the orchid plant to avoid waterlogging and root rot or lack of space for root growth.
2.2 Division
When the orchids are full in the pot, division propagation can be carried out. Generally, 4 old, middle, and young connected orchids can be divided. Division propagation can be done at any time of the year, but it is best done during the dormant period of the orchids.
Place the pre-prepared planting materials on the cement ground and expose them to the sun for more than 2 days, or spray the planting materials with a 50% formaldehyde solution diluted 50 times and seal them for 15 days before use. Do not water before dividing, wait until the potting soil is slightly dry, then tap the pot edges to loosen the planting materials, turn the pot upside down, hold the pseudobulbs with the left hand, tap the bottom and edges of the pot with the right hand, and then push the root soil downward with the thumb from the bottom hole. After the orchid plant is removed, wash the roots, place them in a well-ventilated area to dry, cut off the rotting roots, empty roots, withered leaves, and diseased leaves, and finally cut off the old, middle, and young 4-cluster orchids and disinfect the wounds with charcoal or sulfur powder.
2.3 Planting
According to the characteristics of orchids, they should be planted shallowly. Cover the drainage holes of the prepared orchid pot with tiles, add red brick particles to 1/4, then add the planting materials from coarse to fine, depending on the length of the orchid roots and the size and height of the pot. Place the orchid plant in the center of the pot, when the planting materials cover the roots, gently lift the roots to make them naturally spread out, press the soil, and finally add ceramic particles or breathable small stones. The soil in the center of the pot should be slightly higher than the edges, and the soil around the edges should be 1 cm away from the pot edge. Water after 12 hours.
2.4 Water and fertilizer management
2.4.1 Watering
Watering orchids should follow the principle of "no watering when not dry, and watering thoroughly when watering." The following six points should be observed when watering: 1) Determine the watering time and interval based on the seasonal weather changes; 2) Water in the morning between 7:00-9:00 in spring; 3) Water in the evening between 18:00-20:00 or early morning between 5:00-6:00 in summer; 4) Water in early autumn as in summer; 5) In deep autumn, when the temperature is similar to spring, refer to the spring watering time; 6) In winter, water less or not at all, with the best watering time being noon on sunny days.
2.4.2 Fertilization
Fertilization should follow the "six principles of non-application," which are: do not apply to newly planted orchids, in cold weather, at noon, in the hot season, during rain, or to weak and diseased plants. Orchids grow slowly and require a small amount of fertilizer. For healthy orchids, fertilize with a dilute liquid fertilizer every 10-15 days during the growing season, mainly as foliar feeding, supplemented by root feeding, and avoid direct contact with the roots to prevent root burn and the growth of harmful pathogens. Orchids can be fertilized with organic and inorganic fertilizers, and organic fertilizers must be fully fermented before use, mainly as top dressing.
2.5 Disease and pest control
Common orchid diseases include rot, leaf spot, anthracnose, and white rot, while the main pest is the scale insect.
2.5.1 Rot disease
Take full sun in early spring and late autumn, and properly shade in summer. During the susceptible summer season, appropriately adjust light, temperature, water, and humidity. For orchids with mild symptoms, use 10% benomyl 60-70 g diluted in 15 kg of water, and spray 3-4 times continuously, or use 50% thiram 600-800 times liquid, spray and water continuously for 2-3 times. For severely affected orchids, retain valuable ones and re-disinfect and plant.
2.5.2 Leaf spot disease
Leaf spot disease is a fungal disease that affects leaves and can occur throughout the growing season. Control measures: improve ventilation conditions, promptly eliminate pests; spray 70% methyl thiophosphate 1000 times solution at the beginning of the disease.
2.5.3 Anthracnose disease
Anthracnose disease is the most common and widespread disease in orchids. Promptly cut off the diseased leaves and incinerate them, maintain appropriate ventilation and light conditions in the orchid room. Spray the medicine at the beginning of the disease, using 70% methyl thiophosphorus 1000 times solution or 50% carbendazim 800 times solution or 10% benomyl 60-70 g diluted in water, pay attention to the rotation and mixed use of the pesticides.
2.5.4 White rot disease
Improve ventilation conditions. Since white rot disease is prone to occur in acidic planting materials, mix 1/10 of wood ash or apply 0.3% lime water when planting to raise the pH value to around 6.5, which can reduce the incidence of this disease. After the disease occurs, use 50% carbendazim 1000 times solution or 70% wettable powder of chlorothalonil 800 times solution, and control every 7-10 days, for 2-3 times.
2.5.5 Scale insect
Scale insects are the main pests of orchids. Preventive measures should be taken, strengthen ventilation and lighting, brush off a small number of insects with a brush in time, and apply insecticides at the key period, that is, before the wax layer of the scale insect is formed. You can choose to spray 1000 times of phosphorus emulsion or "Jiuzhou Husha Shen" scale insect killer 100-200 times solution, for 2-3 times. This pest can easily develop resistance to pesticides, so pay attention to the rotation of drugs.
The above is a detailed introduction to how to care for potted orchids, their planting methods, and precautions, hoping to bring some knowledge of flowers to green plant enthusiasts.