For aphids
, use plant-based insecticides by spraying the affected areas. Garlic juice, onion juice, pepper juice, and orange peel juice can be used. Cut these plants into small pieces, and place one teaspoon of chopped onion or half a teaspoon of crushed garlic in a glass of water and let it sit for 24 hours. Then water or brush the affected areas several times. Alternatively, grind 50-70g of bitter pepper, boil it in 0.5-0.7L of water for 1 hour, cool for 24 hours, filter, and store in a glass bottle with a frosted stopper. Before use, add 8-10g of the pepper extract and 4g of laundry soap to 1L of water, mix well, and spray to wash the plants. This method is suitable for controlling piercing-sucking or chewing pests. Another method involves crushing 1000g of fruit peel (orange, tangerine, lemon) in a grinder, adding 3L of water, placing it in a glass bottle, sealing it tightly, and storing it in a warm, dark place for 5 days and nights. After stirring well, filter through gauze, quickly pour the resulting concentrate into a bottle, seal it with a stopper, seal it with paraffin wax, and store it in a cool, shaded place. When spraying, add 25g of the concentrate and 10g of laundry soap to 2.5L of water, stir well, and use. Aphids will be eliminated after 10 days. Tobacco leaf extract is also very effective in controlling aphids. Soak 200g of yellow tobacco leaves in 5L of water for 24 hours, then boil for 2 hours and filter to obtain the concentrate. Before use, dilute it at a 1:1 ratio and add 200g of soap to 5L of diluted tobacco solution. Since aphids are attracted to yellow, yellow boards coated with heavy oil can be hung around flowers or in the growing environment to effectively trap and remove them. For chemical control, spray with dimethoate, pyrethroids, etc.

II. **Red Spider Mites:** Spider mites can be controlled by rinsing the plants with cool water, or by using plant-based pesticides. Soak 8g of pyrethrum in 50g of alcohol for 15 days to form a stock solution. Before use, mix 6 parts of the stock solution and 1 part of diluted soap solution in 20 parts water and stir well. Alternatively, soak 600g of fresh or 300g of dried potato stems and leaves in water for 4 hours, filter, and spray the affected plants. However, this solution is not suitable for some plants, such as cacti and fuzzy plants. Turpentine and garlic juice gas can also be used to kill spider mites and aphids. Arrange the diseased plants around a small dish containing turpentine or garlic juice, cover tightly with plastic film, and after 3 hours, rinse the plants with clean water. Repeat this process several times. If possible, spray the entire plant with miticides such as acaricides or trichlorfon for control.

III. **Scale Insects:** Scale insects are pests with piercing-sucking mouthparts. The larvae crawl on the plant, while both adults and larvae suck the plant's sap. Affected plants develop yellow leaves and deformed branches, losing their ornamental value. Chemical control is most effective during the larval stage; however, adults have a waxy coating that makes it difficult for most pesticides to penetrate. Some scale insects secrete a honey-scented sticky substance that attracts fungi, which then cover the plant, turning it black and causing poor growth or even death. To control scale insects, carefully remove and wipe them clean by hand, then wash the plant with a solution of 1 part soap or laundry detergent dissolved in 6 parts water. Alternatively, spray the entire plant with a solution of eucalyptus oil. For severe infestations, specialized pesticides such as chlorpyrifos or carbendazim are necessary.

4. **Thrips:** Thrips are black or brown, about 1 cm long. They cause severe damage during spring and summer, and thrive in warm, dry environments. Thrips typically inhabit the undersides of leaves, curling them into nest-like shapes to feed on leaf sap. Initially, affected leaves develop many shiny spots, later fading to brown, accompanied by leaf, bud, and flower drop. Thrips secretions can cause sooty mold, increasing the likelihood of disease and diminishing the plant's ornamental value. Control methods generally involve timely spraying with garlic juice; in severe cases, chemical pesticides such as dimethoate, cypermethrin, and lambda-cyhalothrin are necessary.

5. **Whiteflies:** These insects are common in indoor plants, feeding on the undersides of leaves and causing significant damage, especially to poinsettias and cinerarias. They are only 2-3 mm in size, white, and covered in fine hairs. Yellowing leaves will appear on affected plants within about a week, and they will fall off in large quantities, leading to poor plant growth and severe weakness. Because whiteflies are good fliers, a small amount of laundry detergent must be added to the solution when spraying garlic juice or eucalyptus oil. This will increase the adhesion of the pesticide and improve its effectiveness. Alternatively, pesticides such as aphid-killing agents can be used for control.

6. **Powdery Mildew:** Powdery mildew causes a white, sticky substance to appear on the leaves and branches of plants. Affected leaves curl, twist, and dry out, and the plant fails to flower. Prevention methods include ensuring sufficient sunlight, good ventilation, and regular fertilization. For infected plants, spray the entire plant with copper sulfate soap solution or crude sodium carbonate solution (4-5g dissolved in 1L of water). Spray infected plants with a mixed fertilizer solution weekly to increase their resistance.

7. **Root Rot:** Root rot causes plant roots and stems to turn black and rot. Causes include excessively moist soil, insufficient light, poor ventilation, high temperatures, and excessively concentrated plant sap. Prevention requires proper care and management. Prune plants regularly according to their specific characteristics, maintain adequate nutrients, keep the temperature suitable, and irrigate the soil with potassium permanganate (3g in 1L of water) or spray with onion juice (20g of chopped onions in 1L of water, soaked for 24 hours, then filtered). Spray 2-3 times every 6 days.

8. **Leaf Spot Disease:** This disease mainly affects indoor foliage plants, caused by poor ventilation and unsuitable lighting. Affected plants typically develop yellow or brown spots of varying sizes and shapes on their leaves, severely impacting their ornamental value and potentially worsening. Control measures include using garlic juice (25g of crushed garlic mixed with 1L of water and soaked for 24 hours), spraying the plant with a cloth every 6 days. Alternatively, a solution of 1g salicylic acid, 3g baking soda, and 5mg alcohol diluted 3-5 times can be used. For fungicides, potassium permanganate, carbendazim, and chlorothalonil can be used.