How to Use Isarid Mycoinsecticide for Effective Biological Control
Nov 07, 2025
Isarid Mycoinsecticide is a biological insecticide designed for growers looking for reliable, plant-safe control of thrips, whiteflies, aphids, and other soft-bodied insects. As a fungal insecticide based on the entomopathogenic fungus Isaria fumosorosea strain FE9901, Isarid provides an effective alternative to chemical pesticides and synthetic insect sprays. Instead of relying on chemical toxicity, Isarid works through a natural infection process. After spraying your plants, the spores attach to the insect’s cuticle, germinate under warm and humid conditions, and penetrate the insect’s body. Inside the pest, the fungus grows as mycelium and consumes internal nutrients until the insect dies, typically within three to seven days. Because this process is physical rather than chemical, insects cannot develop resistance or immunity to Isarid, making it an excellent long-term tool for biological pest control and organic insect management.
Isarid Best Practices Leaflet - Download
Isarid is highly effective for thrip control, aphid control, and whitefly control, in large part because these insects have soft bodies and reproduce extremely quickly. Rapid reproduction is one of the main reasons chemical insecticides begin to fail. When the same chemical is used repeatedly, a small percentage of naturally tolerant insects survive and reproduce. Over many generations, the population becomes more resistant to that chemical. Isarid avoids this entirely. No matter how quickly thrips, aphids, or whiteflies reproduce, they cannot evolve immunity to fungal penetration or internal colonization. This makes Isarid one of the most reliable tools available for resistance-proof insect control, both in greenhouses and indoor plant environments.
Because Isarid contains living fungal spores, proper preparation supports even dispersal and consistent results. The bucket should remain refrigerated during storage, but warming it to room temperature before mixing helps the spores separate cleanly instead of clumping. If the product is used while still cold, the spores can bind together and fail to disperse properly in water. Once warmed, Isarid can be mixed directly into water and diluted as needed without special steps. The product should not be applied through high-heat fogging or thermal fogging systems, because elevated temperatures will deactivate the fungal spores.
Environmental conditions have an important influence on how quickly Isarid works. Isaria fumosorosea performs best when temperatures are above 70°F and humidity is above roughly 50%. These conditions support faster germination and more effective infection, leading to quicker results on plants. If conditions are cooler or drier, Isarid will still control thrips, aphids, and whiteflies, but the visible decline may be slower. Because ultraviolet light can damage fungal spores, the most effective times to apply Isarid are early morning, late afternoon, during cloudy conditions, or inside greenhouses where UV is naturally reduced. When warm temperatures, humidity, and low UV occur together, Isarid’s biological infection cycle moves efficiently, and insects decline within the typical three-to-five-day window.
Although Isarid begins working immediately after spray contact, visible results require time due to the nature of fungal infection. The spores must attach, germinate, penetrate, and grow internally before the insect dies. This process is very different from chemical “knockdown” sprays and is one of the reasons Isarid is considered a natural insecticide rather than a fast-acting neurotoxin. The decline is steady and reliable, and when humidity remains high, the fungus may sporulate on insect cadavers, releasing new spores that continue the biological control cycle naturally.
One of Isarid’s key advantages is its compatibility with beneficial insects and biological IPM programs. Many chemical insecticides cannot be used once predatory mites, parasitoids, or other beneficial insects are active. Isarid, however, does not harm these natural enemies, making it ideal for integrated pest management. You can continue applying Isarid while beneficials remain active on your plants, giving you both fungal infection and natural predation working simultaneously. Because of this compatibility, Isarid is widely used in greenhouse pest control, indoor plant IPM, and organic gardening programs.
Isarid also pairs effectively with certain supportive materials. Insect growth regulators like AzaGuard or Enstar can weaken insect cuticles and disrupt normal development, making fungal infection easier. Oils such as SuffOil-X or TriTek can improve leaf coverage and spore contact, helping compensate for sub-optimal humidity. However, Isarid should not be mixed with oxidizers such as ZeroTol or acidic products like citric acid, as these materials can damage the fungal spores and reduce performance.
For growers looking for a dependable, residue-free, resistance-proof solution that is safe for plants, compatible with beneficial insects, and effective in both organic and conventional programs, Isarid Mycoinsecticide is one of the strongest biological insect control options available. Its fungal mode of action offers a unique advantage for long-term suppression of thrips, aphids, whiteflies, and similar soft-bodied insects across all plant environments.
You can purchase Isarid Mycoinsecticide here.
