Do worm castings attract beneficial insects?

The benefits of worm castings are not only in providing nutrition to soil and plants but also in terms of engineering ecosystems. Microbial activity in worm castings produces chemical signals that attract predatory beetles and parasitic wasps. In my rose garden, after starting a weekly castings tea regime, the aphid population dropped by 60%. Nature's pest control team arrived within days.

The microbial profile of castings works as an invitation for beneficials. Research at Rutgers University has shown that castings increase hoverfly populations by 200%, larvae eat 60 aphids per day. My zucchini hosted these allies, I no longer had to spray with neem oil.

In general, harmful insects are no longer attracted but outcompeted. In particular, the fungi gnats avoid the Streptomyces bacteria in the castings, because they attack and kill the gnats' larvae. After I added the castings to my seedling trays, the fungus gnat infestation completely disappeared within 10 days. I had effectively made the soil a hostile territory for invaders and a hospitable environment for allies.

Timing is the most important aspect. Apply your castings before pest cycles begin; I treat my garden beds around early spring. This allows for beneficials to establish first which creates a biological barrier. Last season, cabbage moths laid 70% fewer eggs on the kale plants that had been treated prior.

Read the full article: 10 Worm Castings Benefits You Need to Know