Common Pest and Disease Types of Potted Flowers and Their Control Methods

Potted flowers not only help beautify the environment but also regulate the air. Most households grow potted plants, so what are the pests of potted flowers? How to control them? Many people are probably not very clear about this. Next, the editor summarizes for you what the pests and diseases of potted flowers are and how to control them.

1 Diseases

Common diseases of indoor flowers include leaf spot diseases, powdery mildew, and others.

1.1 Powdery mildew

1.1.1 Occurrence characteristics. Powdery mildew is a common fungal disease, mainly harming the leaves and tender branches of many flowers such as Chinese rose, peony, cineraria, primrose, Chinese peony, chrysanthemum, Polygonum criopolitanum, fuchsia, and others. When the temperature reaches 18°C-30°C, it is extremely easy to develop if ventilation is poor. The affected plant first shows yellow spots on the leaves and grows a layer of powdery white substance. When the outbreak is severe, flowers are few and small, leaves wither, and even the entire plant dies.

1.1.2 Control measures. (1) Pay attention to ventilation, control humidity, and strengthen light, which can prevent the occurrence of powdery mildew. (2) Strengthen daily management. When watering, use root irrigation and minimize water spraying on leaves to reduce air humidity. (3) Remove diseased leaves and diseased buds early and bury them deeply. (4) Chemical protection: at the early stage of the disease, spray 25% triadimefon 1000-2000 times solution, or 50% carbendazim 500 times solution.

1.2 Leaf spot diseases

1.2.1 Occurrence characteristics. Leaf spot disease is a common fungal disease. It includes types such as black spot and brown spot, and harms the leaves of many flowers such as Chinese rose, rose, Chinese peony, chrysanthemum, clivia, and others. The affected leaves have black or brown round or irregular spots and concentric ring spots. When humid, black mold layers and small black dots often appear, reducing the ornamental value of the flowers.

1.2.2 Control measures. (1) In combination with daily maintenance and management, promptly remove dead branches, fallen leaves, and diseased branches, and burn or bury them deeply to reduce sources of pathogens. (2) Pay attention to ventilation indoors, lower the temperature, and do not place pots too densely, so as to facilitate ventilation and light transmission. (3) Chemical protection. Spray 200 times 0.5% equal-amount Bordeaux mixture or 70~, 4 thiophanate-methyl 1000 times solution, etc.

2 Pests

Pests are mainly aphids, scale insects, spider mites, whiteflies, and others.

2.1 Aphids

2.1.1 Occurrence characteristics. Aphids, commonly known as greasy insects or honey insects, harm many flowers. They mainly gather on tender shoots, flower buds, and the undersides of leaves to pierce and suck plant sap, causing leaves to curl and turn yellow, plants to grow slowly, and normal flowering to be affected. At the same time, the large amount of honeydew excreted by aphids can induce sooty mold, seriously affecting photosynthesis.

2.1.2 Control measures. (1) Check promptly. After finding a small number of aphids, they can be brushed off with a writing brush dipped in water, avoiding damage to tender shoots and tender leaves. The brushed-off aphids should be disposed of cleanly in time to prevent spread. (2) Take 2-3 tree-of-heaven leaves, cut them into pieces, add 10-15 times water, boil for 1 h, and use the filtrate in a sprayer to kill aphids. (3) Break one chicken egg or duck egg into a bottle, add 1-2 ml cooking oil, then add 200 ml cold water, cover the bottle, shake up and down several times, wait a moment, and once no oil droplets float on the liquid surface, it can be sprayed. It also has a certain effect on aphids and spider mites. (4) Take 20 g dried chili peppers, add 1 kg water, boil, and use the clear liquid to spray and kill pests such as aphids and mites.

2.2 Spider mites

2.2.1 Occurrence characteristics. Spider mites, also known as red spiders, are small and red, and can be seen with the naked eye. They occur more under high temperature conditions and often gather in large numbers on the undersides of leaves to pierce and suck sap. Some have the habit of spinning webs and can harm many flowers, such as Chinese rose, peony, hollyhock, winter jasmine, camellia, geranium, and others. The front of the affected leaves shows yellow spots, and in severe cases they wither and fall off, harming flower growth.

2.2.2 Control measures. (1) Increasing humidity and providing appropriate ventilation can reduce the breeding of spider mites. (2) Spray tobacco water. Formula: 40 g tobacco powder, add 1 kg water, soak for 48 h, then filter. When using, add another 1 kg water to the stock solution, plus 2-3 g washing powder, stir evenly, and spray. (3) Take 4 g flour, put it into a porcelain bottle, add a little water to make a paste, then add 200 ml boiling water, cool, filter, and spray. (4) Cut ordinary laundry soap into thin slices, dissolve with boiling water (add water at a ratio of 1:60-70), and spray after cooling to control spider mites and aphids. If soap water is used to soak cigarette butts, it can improve the control effect and also control whiteflies, leafhoppers, and others.

2-3 Whiteflies

2.3.1 Occurrence characteristics. Whiteflies, also known as small white moths, are common pests in greenhouses or rooms and can harm many flowers, such as fuchsia, hibiscus, Chinese rose, cineraria, orchid, peony, fig, and others. They often gather on the undersides of leaves and pierce and suck sap, with tender leaves suffering most severely. In severe cases, leaves wither and fall off, and the excrement of adults often leads to the occurrence of sooty mold.

2-3.2 Control measures. (1) Cut the branches and leaves of oleander into pieces, add water, boil for half an hour, and filter to spray and kill whiteflies, aphids, and scale insects. (2) Take a small wooden stick, tie a small cotton ball to one end and dip it in dichlorvos solution, and insert the other end into the pot of the affected plant. Pests such as whiteflies and aphids will soon be killed. If the pest infestation is relatively severe, then cover the flower pot with a plastic bag, and after 4-5 h the pests will be fumigated to death. (3) Dilute washing powder with water 400 times and spray on the insect bodies, once every 5-6 d, spraying 2-3 times in succession, which can kill whitefly adults, eggs, and nymphs. At the same time, it can also control aphids and scale insects. Soap water and washing powder water should not be used for a long time, otherwise it is easy to make the potting soil alkaline, which is not conducive to flower growth.

2.4 Scale insects

2.4.1 Occurrence characteristics. Commonly known as tree lice, they have many species and harm many flowers, such as fig, Chinese rose, peony, Rosa acicularis, hydrangea, camellia, mulberry, and others. Affected plants grow slowly, and branches and leaves wither and turn yellow. At the same time, the large amount of honeydew excreted by scale insects can induce the occurrence of sooty mold.

2.4.2 Control measures. (1) Check promptly and control early. When the number of insects is small, they can be manually brushed off with a brush or bamboo piece, or the affected branches and leaves can be cut off and burned together. (2) Take 1 part each of cigarette butts and cigarette ash from an ashtray, add 40-50 parts water, soak for 1 day and night, mash, filter, and spray. It has a certain effect on newly hatched scale insects. (3) Refer to the control measures for whiteflies.