Effective Control Methods for Spring Flower Pests and Diseases

<1> Aphids: also known as honey bugs. Many potted flowers are harmed by aphids, such as peach, Chinese rose, elm-leaved spirea, plum blossom, cherry blossom, etc. Aphids mostly gather on the underside of leaves and live by sucking leaf sap. Because of their fast reproduction rate, as the temperature rises in early spring, the damaged leaves cannot unfold normally, new shoots cannot grow, and in severe cases the leaves fall off, affecting flowering. When the high temperatures of summer arrive, some aphids migrate to other plants such as vegetables, and do not fly back to the trees to lay eggs and overwinter until early winter. Its control methods include: after budding and before leaf unfolding, spray 1000 times 40% dimethoate emulsion to kill the newly hatched young aphids; alternatively, do not spray pesticide at first, to protect natural enemies such as ladybugs and let them eliminate the aphids, until the imbalance of population growth and decline means the natural enemies cannot control the aphids, and then consider using pesticide. When using this method, it must still be combined with the auxiliary method of manually picking up and crushing the aphids.

<2> Scale insects: scale insects have the most species and harm the most flowers and trees among pests. Tortoise shell scale, white lipid, round. Mulberry white scale, white, pointed. Oyster shell scale, dark brown, males elongated, females round. Armor scale, dark brown, round, shaped like armor. Plants susceptible to scale insect damage include camellia, pomegranate, oleander, rhododendron, hibiscus, cherry blossom, plum, peach, crabapple, Chinese rose, etc. The larvae first suck sap on the leaves, causing the leaves to lose green, and as adults they mostly suck sap on the branches, severely weakening the tree vigor and affecting flowering. Its control methods include: crushing the pests by hand or scraping them off the leaves and branches with a small knife, and spraying 1000 times 40% dimethoate emulsion 1 to 2 times during the larval stage, with an interval of 7 to 10 days between applications.

<3> Red spider mites: mite class. The body is small, almost indistinguishable to the naked eye. They mostly cluster together and reproduce extremely fast. There are many plants susceptible to damage, such as Chinese rose, rose, flowering peach, cherry blossom, rhododendron, etc. The mites cluster on the underside of leaves and suck sap, first causing the leaves to lose green, and ultimately causing leaf fall and new shoots to wither and die. In severe cases, small trees grow weakly and even die. Its control methods include: spraying 1000 times 40% dimethoate emulsion, or 1000 to 1500 times 40% trichlorfon acaricide emulsion at the initial stage, and spraying must be thorough and dense. At high summer temperatures, this pest reproduces fast and control is often too late, so pesticide should be sprayed early, and continuously 3 to 4 times, with an interval of about 7 days between applications, and the same pesticide should not be used alone, to avoid developing resistance.

<4> Nematodes: nematodes harm plant roots and cause abnormal plant development. Affected plants include orchid, carnation, narcissus, peony, etc. When the pest damage is light, it is often not easy to notice. When the pest damage is severe, the plants grow poorly and do not flower well. Because there are many kinds of nematodes in the soil and the bodies are tiny, almost invisible to the naked eye, prevention must be the main approach; 20 to 30 granules of 3% furadan granule agent can be added per kilogram of planting soil, and through soil dissolution it is slowly released to eliminate nematodes.

<5> Caterpillars: including tent caterpillars, boat-shaped caterpillars, etc. Their feeding habits are very mixed, harming almost all plants, and they appear in outbreaks. They must be controlled early. The main method can be manual catching, and when necessary, spray 1000 times 40% dimethoate emulsion.

<6> Underground pests: white grubs, that is, the larvae of scarab beetles, white. Cutworms, green-black. In the soil they live by feeding on plant roots or the root crown, often causing plant death. The control method is to dig them out promptly from the holes where they enter the soil.