Student Blog Post by: Michelle Fraser and Jesse Gallant
Our class recently had the opportunity to tour the greenhouses of Butchart Gardens as well as Eurosa Farms, and the tropical terrariums of the Victoria Butterfly Gardens. We quickly noticed that a major factor ensuring the success of such large commercial operations is pest management. Integrated Pest Management or IPM, as it is commonly known, is a holistic approach to managing pests. Its design is to minimize risks to people and the environment. This approach focuses on using the right plant, in the right place and echoes the importance of a systems-based framework.
From a gardeners perspective, the twenty-six greenhouses at Butchart Gardens were equally as beautiful as the world-class ornamental gardens on display. Stunning container plantings and blooms were found everywhere we went, all housing healthy and lush plants, thanks to the abundance of IPM practices. Mature tree lines hug the property and create unique micro-climates for each of the greenhouses. Swinging back to the concept of right plant, right place, it is vital to grow plants best suited to their natural environment. This ensures the plant is provided the best opportunity to grow into a healthy, mature plant free of pests. Greenhouse staff at Butchart rotate plants throughout the various greenhouse micro-climates to ensure healthy crops. When a pest does manage to take hold of one of the greenhouses, the plants are closely assessed and then monitored before any treatments are applied. Biological controls such as predatory insects are the basis of Butchart’s IPM strategy. The IPM mantra is to “start clean, and stay clean”, and to be successful in biological control measures. Early detection is key, to prevent prolonged and more permanent damage to plants. Pest preventative measures are abundant within the greenhouses. One important preventative control measure is having a limit on the amount of new material that goes into the greenhouses. This is to avoid the introduction of new pests, as is the implementation of good sanitation practices.
Head grower, Paul Bulk, is the brains behind production at Eurosa Farms, the largest supplier of fresh cut flowers in Victoria. He walks us through the isles of plants answering our machine-gun spray of questions with ease. It’s clear that growing plants is in his blood. On our walk, he outlines the various IPM strategies that keep his plants healthy and hardy. The first major issue to control, he mentions, is powdery mildew. Picture your lunch in a tupperware container, what happens if you leave it in the sun all day? Condensation, moisture, heating and then cooling occurs when the sun sets. Your lunch will probably look pretty soggy by bedtime, right? This is similar to what happens in a greenhouse except with plants. But what comes with unsolved moisture? Mould and mildew. Look up and you’ll see orange lantern-like fixtures hanging above each row of plants. In these fixtures is sulphur. Eurosa combats mildew by melting the sulphur into the air, which effectively veils itself over and onto the foliage of the plants. The key is to melt the sulphur, not burn it. Plants hate sulphur dioxide even more than humans do! Suddenly, our attention is diverted and a black ribbon slashes its way through the endless rows of plants. Cats! Cats are a simple, yet effective way of keeping rodents from munching and nesting in the greenhouses. As Paul guides us through our large-scale tupperware adventure, we notice another curious thing… a mature cucumber plant growing at the front of each of the rows of alstroemeria flowers. So, what gives? Isn’t this a cut flower operation? It turns out that cucumbers are great indicator plants and succumb more quickly to pests and diseases than other plant types. This gives Paul and his crew the time to stop a potentially devastating pest or disease before it wipes out the crop. Also, upon taking a closer look, each cucumber plant is tagged with a circular grommet. These circular pads host parasitic wasp eggs, which hatch and then feed on smaller pests like spider mites. Understated and natural solutions to large-scale problems. IPM at its finest – ingenious Paul!
At the Victoria Butterfly Gardens, our fearless and passionate leader, Justin Dunning, directs us through a (literal) jungle of plant and animal activity. Above our class floats a carefree kaleidoscope of butterflies that overwhelm the senses. Parrots, tortoises, coy, flamingos, an iguana named Jerome crosses the path. Then something else happens – a not so magical guest rears its ugly head. A big fat cockroach. People hiss and the birds go silent, Jerome scuttles away. Wait, “it’s OK” assures Justin. These cockroaches are here for a reason. That reason is IPM. Justin explains that only around six species of cockroach are invasive. There are, in fact, thousands of good ones! Phew. And that’s what these guys are here for, to eat nasty things like scale insects, mealy bugs and many other tiny pests.
Upon further reflection, proper pest management goes much deeper than mindlessly spraying chemicals or mechanically separating pest from plant. It is understanding how to manipulate an ecosystem in a way that is both natural and efficient. This can often mean using unlikely companions and methods of control. Pest for pest, slow melt, furry friends – think outside of the tupper – er – I mean box!