Recently in my greenhouse I had a little pest outbreak. I was checking on the beautiful petunias and gazanias when I noticed something strange. Tiny, yellowish, swollen creatures clung to the leaf surfaces, still or crawling very slowly.
For several days they increased in numbers, and I went into complete panic mode. Was it some kind of mite? I prefer not to use dangerous chemical sprays so I whipped out my insecticidal soap and went to town, spraying the undersides of leaves and over the tops. In a couple of days, I noticed the little creatures were gone. “Great!” I thought, as I declared victory to myself. I defeated those whatever they were and I felt accomplished.
Fast forward a week or two later. I was working in the greenhouse while listening to a gardening podcast. It was about beneficial insects in the garden. The podcast guest described how a parasitic or parasitoid wasp lays a single egg into the body of an aphid. The larva slowly mummifies the aphid as it consumes it from the inside out. Soon it emerges through a tiny hole chewed through its back and flies away to repeat the process.
My heart just sank! Oh no! What had I done? I went into my son’s bedroom and found his toy magnifying glass. I searched for any remaining creatures from those I had eradicated before, and luckily, I found a couple in the far corner of the greenhouse. Yep, my fear was true. The little creature was swollen and hard and had a tiny hole in its back where the little wasp chewed its way out and flew away. Probably right into my insecticidal soap. How could I be so stupid? Why didn’t I take an integrated pest management course in college? I felt terrible.
After a week or so I had a huge problem with aphids on nearly all of my young plants. My brain wanted to go right back into damage control mode, but I resisted the urge to whip out that spray. Instead, I opened the greenhouse doors every day and hoped that someone good would fly in. I had seen signs of ladybugs on my cilantro flowers outside and I really hoped maybe they would get the message there was a juicy aphid buffet in the greenhouse.
I am happy to report that yes, there have been ladybugs and their larvae spotted in my greenhouse. The aphid problem still exists, but I am confident that these good bugs will slowly take care of the problem or at least bring it back into balance. Balance, not perfection! I also released lacewing larvae and have seen some adult lacewings on the plants.
The moral of this story is that I am still learning, and that nature really can take care of herself. She works slowly, but if we are patient and support her the best we can, by not using sprays (even organic ones), and planting things that attract and support the precious beneficials (a topic for a future article), it really is the best. Even though a natural spray claims it won’t harm ladybugs and other beneficials, it will harm the eggs and larval forms of those beneficials.
My goal from now on is to try and identify every bug or insect I see in my yard or greenhouse and take a note of who eats whom. I am also planning to grow plants that attract those beneficials. (If there is an exotic pest problem that has no natural enemies then maybe a spray would be ok.)
What to plant in May: all summer vegetables and herbs. Don’t plant any more cool weather plants such as lettuces, brassicas, or cilantro (unless you want to attract some of the good guys with the flowers). It will be way too hot for these.
News: We are opening a plant nursery in town! By the time you are reading this, Patagonia Plants should be open at 308 Naugle Avenue in Patagonia. I am very excited to grow and source only locally grown vegetables, flowers, herbs, trees, and shrubs that perform in our area of southern Arizona. We plan to carry locally made bagged compost, potting mix, and soil amendments as well as garden gifts, house plants, succulents and more. Thank you to everyone who has given me support so far!