Neonics, greenhouse plants, and pollinators
I recently received a question about mail-order plants and the widespread use of insecticides commonly called “neonics” (neonicotinoids) in large production greenhouses. The writer wanted my advice on whether to keep or cancel her order with Burpee’s (but this could refer to any large plant-producing company). Note that the writer’s order included seeds and rootstock, and she was using the plants to build a pollinator garden.
Q: I've been thinking about how you mentioned that greenhouse grown plants can be covered in pesticides. I was wondering if I might be better off canceling my Burpee order and finding the plants locally?
A: Great question – remember that plant producers use specific pesticides to deal with specific pests. Neonicotinoid pesticides are used on greenhouse pests that are infesting actively growing plants. Seeds don't fall into this category, and I suspect that most of the plants you're getting via Burpee are going to be rootstock, not plants that arrive with leaves, stems, and flowers on them. However, it’s very possible your rootstock plants were grown with neonics last year.
When neonics first became available, they were considered a godsend by greenhouse managers. Not because they were more effective at killing insects, but because they were far less toxic to their human employees. What’s that saying: Two steps forward, one step back? Because neonics are a systemic pesticide, they eventually inhabit every plant cell including the foliage, nectar, and pollen. Beneficial insects that feed on these plants are equally at risk as the original greenhouse pests. The science is unclear on whether a plant can “outgrow” the neonics, and at what rate it might occur. If you’re buying plants for pollinator consumption, I would avoid plants grown with systemic insecticides completely.
An advantage to mail-order plants is that you know exactly what’s available (and it’s fun to shop online in January!). There’s no guarantee that you’ll find, say, lupine in local garden sales. I buy mail-order plants when I’m looking for specific species and cultivars that may not be available in local nurseries (this year: tissue-culture raspberries, asparagus, certified seed potatoes, native plant seed, etc.). There are reliable sources of top-quality plants and seeds being produced without broad-spectrum, persistent pesticides – check out Seed Savers, Prairie Moon, Bakers Creek, High Mowing Seeds, and Johnny’s Seeds, among many other organic/non-GMO companies. Even Burpees has a line of organic seeds (but not plants - yet). If we demand organic plant stock, even a giant company like Burpees will pay attention and provide us with more neonic-free products.
On the other hand, supporting local organic growers is a good thing to do, even if it costs a few more dollars. Plus they usually offer plant varieties that have grown well in our climate and soil. I’ve already heard of 4-5 local plant sales taking place in April-May; keep an eye on my newsletter for updates as we get closer to those dates.
It comes down to deciding what is important to you, and what your goals are for your garden