Every spring, I get a little excited when I see this:
Aphids. And not just one or two aphids here or there (is there even such a thing? I heard once that aphids are born pregnant, though that’s probably just hyperbole), but loads and loads of aphids. Just look how they’re covering that rosebud! Every other rosebud on the plant was also absolutely loaded with aphids when I took this photo, and the critters are on other plants throughout the garden, too. But really, I don’t mind. I actually really enjoy seeing aphids on my plants in the spring. And this is why:
and also this:
as well as countless other beneficial insects that are a little more camera shy than my friends the ladybug and the soldier beetle.
You see, I don’t use pesticides in my garden – no, not even organic pesticides (which certainly do exist, but are not necessarily nontoxic!). The one place I do occasionally use insecticides is in my greenhouse, because it is apparently such an inviting climate for the bad bugs and, for some reason, not so attractive to the good bugs. When I do spray in the greenhouse, I use plant-based horticultural oils, which are nontoxic and basically work by smothering insects and their eggs. But why don’t I use organic sprays to combat aphids and other nasties in the garden?
A lot of people assume that if a spray is “organic” or “natural”, it is nontoxic and completely safe to use (I used to run into this misconception a LOT during the nine years that I worked at a garden center). However, even natural insecticides that are approved for use in organic gardening can be toxic to humans, wildlife, and/or fish. (If it kills bugs, don’tcha think it just might be poisonous to other critters, too?) Not all sprays that fall into this category are toxic; generally, if it works by physical means (such as the smothering effect of the horticultural oils) rather than chemical means, it’s considerably less likely that it will be toxic (though it may still be allergenic or an irritant). If it works by chemical means, I recommend doing your research before using it on your garden. One very good example is pyrethrins, a plant-derived (from Chrysanthemum cinerariifolium) insecticide that is quite toxic to fish (and apparently, I just learned, to cats, as well). Pyrethrins do photodegrade rather quickly and so they don’t persist long in the environment; however, they do last much longer in water (where, obviously, they pose a problem to fish). Since the property I live on is bordered by a river, I never use pyrethrins.
Insecticides are non-selective! That means they won’t just kill the “bad bugs” that you’re targeting, but the beneficial insects, as well (ladybugs, soldier beetles, honeybees, butterflies, beneficial wasps, lacewings, etc.).
Organic insecticides don’t work long-term! (Some of the nastier non-organic insecticides do, which of course means that not only are the bugs going to encounter it in their environment for longer periods of time, but the birds, and the squirrels, and your pets, and your children will as well. Nasty stuff.) Because these insecticides don’t work for very long, you need to repeatedly apply them, meaning more of your time and money is spent on spraying. And, of course, you’re also killing off the beneficial insects which might help you battle the bad bugs in the first place. You’re basically creating a dependency on using sprays in your garden.
Cultivating biodiversity in the garden means things eventually (usually) take care of themselves. By reducing (and hopefully eliminating) the use of insecticides in your garden, you are allowing the aphids and other undesirables to survive, thus providing food for beneficial insects, birds, lizards, etc. In my experience, simply leaving insect problems alone in the garden results in the problems disappearing within a few days. And then there’s the added benefit of being able to watch my honeybees, numerous other native bees, dragonflies and damselflies (oh, I have so many damselflies!), countless other beautiful insects that I can’t name, and numerous species of birds and reptiles (and the occasional amphibian) enjoying my garden along with me.
Oh, and all those aphids you saw in the first photo, as well as all of their friends on the rest of the rosebush? Gone two days after I took the picture. And this is how the rose looks now: