Feeding Aphids for a Balanced Garden

Three years ago a hoard of those little juice suckers ganged up on my artichokes and killed a couple of them. I was helplessly limited in my organic commitment to blasts of water and an occasional bath of insecticidal soap - to no avail. On artichokes aphids cling in the depressions on the under sides of leaves and are nearly impossible to blast out. I did manage to save the stronger plants, but committed myself to finding a better strategy for managing aphids in my food garden.

Step one was simple. Pay much closer attention to the timing and food preferences of aphids. Step two was a little more complex since it involved managing those ant colonies that were protecting the aphid colonies from natural predators. Ahhh, the complexities of nature! The third step was tough, but I had no options. I had to stop doing what I had been doing - killing aphids with water and soap and figure out how to let nature find its own balance. Once I started thinking about it, I realized that I was not only killing the food that attracts aphid predators, but I was also killing the larval stages of those predators. Small chance of achieving a natural balance that way. There I was whacking nature on both cheeks and wondering why my garden was out of balance.

The first thing I noted was that aphids, when given the opportunity flocked to those plants that were blooming. Seems they prefer the nectar of mature leafy green plants in bloom. Great for me since I am done eating the mustards, kales, broccolis and lettuces by that time in their cycle. In fact, the aphids in my garden are predictable, moving from one blooming plant to another as the season progresses. They show up about the last frost date and congregate on blooming Giant Red Mustard – definitely their favorite early season food. Also blooming around this time are the kales – Red Russian and Tuscan. Aphids will take to the Red Russian, but tend to leave the Tuscan Kale alone, until desperation sets in. As soon as the spring broccoli blooms, the aphids are on it like a blanket. Even though some years are not great for spring broccoli, I grow it anyway - makes fine aphid food.

The next aphid favorites to bloom are the lettuces – stimulated by those long days of late spring. I always over plant lettuce in late winter so there are plenty of blooming plants for baking, feeding aphids and for seed. The blooming lettuce carries the remaining aphids right into summer – when they naturally struggle to survive. Actually, by lettuce blossom time the ladybugs and other aphid feeders have honed in on the porky populations leaving few adults to brood new generation.

Aphids will also congregate on the bloom stalks of dill and fennel. In our area, dill needs to be planted during the cooler months, but the fennels will grow year round.

So there you have my approach to aphid management without poison, soap, hosing or tending. I do have to plant broccoli and dill every spring, but the other aphid food plants are naturalized in the garden, reseeding themselves seasonally and leaving me with only thinning, watering and eating.

So what about the artichokes? Well, aphids just do not bother them anymore. This season I could not find a single artichoke-sucking aphid. The combination of preferred foods and abundant predators keeps the aphid population small and well fed, turning them into beneficial insects rather than pests in my garden ecology.

My approach to aphid management is not a cure-all. You can still have aphid problems in the vegetable garden in summer – but they are generally tolerable. Aphid problems can also show up in fall, but fortunately, first frost is nearby. Likewise, this strategy does not work for root aphids, nor has it worked for late melons – melons planted late enough to set fruit in fall.

The loss of a couple of artichoke plants seems worth it now. I learned a lot about natural balance in the pest and predator dance in my food garden, changed my attitude about pests, started a self-sustaining community of edibles for both the aphids and me and got great artichokes with less work.

For more information about what plants to grow for aphids and when to grow them - (link)

till next time,

Darrol Shillingburg
Doña Ana County Extension Master Gardener