To prevent and control diseases and insect pests of medicinal plants, we must first understand the causes of diseases and insect pests, master the laws of their occurrence and development, and implement the policy of "prevention first, comprehensive prevention"; Secondly, it is necessary to comprehensively consider the advantages and avoid disadvantages, not only to improve the yield and quality of medicinal flowers, but also to reduce environmental pollution. In particular, it is necessary to prevent toxic residues from harming the body. After mastering these principles, you can use the following preventive methods:

1. Plant quarantine is a method to control the diseases and pests of medicinal flowers according to a series of quarantine laws and measures formulated by the state, so as to prevent the introduction of new dangerous diseases and pests from other countries or other epidemic areas and limit the spread of local diseases and pests. Therefore, when introducing medicinal plants, the transportation of seedlings should strictly perform quarantine procedures.

2. Agricultural prevention and control is a method to control and eliminate pests and diseases by comprehensive use of cultivation management technical measures, which is called agricultural prevention and control law. The following methods are commonly used:

(1) Cultivate insect-resistant varieties (2) Reasonable rotation (3) Adjustment of sowing date (4) Deep ploughing (5) Clearing fields (6) Strengthening field management.

3. Biological control is called biological control, which uses some beneficial organisms in nature to eliminate or inhibit some pests and diseases.

At present, biological control is mainly carried out by using insect control, fungal control, fungal treatment and bird control. For example, using predatory beneficial insects such as walking insects, aphid-eating ladybugs, syrphids and lizard-eating flies to control aphids; Use Trichogramma and Trichogramma to control Pieris rapae. Using parasitic bacteria and fungi such as Beauveria bassiana, Penicillium and Bacillus to control various pests such as Pieris rapae, heartworm, grub, scarab and cutworm; Use antibiotics such as kasugamycin and "5406" and internal medicine to control Rhizopus and anthracnose. Biological control is an important aspect of integrated control, which has the advantages of non-toxicity, safe use, no residual toxicity, no pollution to the environment, lasting effect, prevention and so on, and has broad development prospects.

4. Chemical control The method of using chemical pesticides to control pests and diseases is called chemical control. It has the characteristics of quick action, good effect and convenient use, and can eliminate or control a large number of pests and diseases in a short time, which is less restricted by regional and seasonal factors. It is a common method to control pests and diseases at present. Attention should be paid to the use of chemical agents: understanding the nature of drugs, prescribing the right medicine, grasping the opportunity, spraying drugs at the right time, mastering the technology, ensuring the curative effect, paying attention to safety, and avoiding drug damage and human and animal poisoning. In recent years, with the development of atomic physics, ionizing radiation has been used to directly kill pests. In addition, lasers can also be used to control pests.