We gardeners can rarely control the challenges that seem to appear with every new season . Horrid plagues and pesky critters show up one year and disappear the next . Gophers,snails, spider mites, blackspot-they all come and go -though one wishes they would just go. Weedy afflictions such as oxalis and spotted spurge are predictable and eradication proof-the only realistic outcome is reduction. There was a lot to like about my garden in 2023 but an unprecedented aphid invasion still leaves me a bit mystified .I fully expect aphids on the roses and sometimes on the hellebores and by June they are usually gone. This year they persisted well into fall . Cutting back the lilies in my front garden this past week I found still living aphids on the back side of foliage that was barely green.
Who gets aphids on Lilies ?? It was a first for me. Every Lily in the front garden was covered in them .
First came the aphids, followed by honeydew and then the sooty mold. I got my box of latex gloves out of the car-previously used for putting gas in my car during Covid. I had many gloves left -didn't need to fill up very often in pandemic times. I used the squish method but I had Lilies that were 6 feet tall and had lots of leaves. I concentrated on the flower buds. If I saw ladybugs or soldier beetles in the area I left the aphids intact for consumption by the predators. But the population was getting out of control and the honeydew was coating nearby plants as well.
In the back yard-more aphids. This Melianthus 'Purple Haze' was particularly victimized especially the lower foliage deep inside the plant. Squishing wasn't a practical option due to the shape and texture of the leaves and there were a number of ladybugs and soldier beetles hanging around on the plant so I let it be for a few weeks. It soon became clear that the plant was too big and too infested for the beneficials to keep up so I used the sharp spray from the hose method to try and at least reduce the population.
These next two photos aren't very clear but basically this Cordyline 'Cha Cha' and the Aster divaricata below were covered with honeydew and subsequently sooty mold, though there were no aphids on the plants them selves.
Meanwhile , aphids were busy colonizing on the bloom spike of Agave 'Blue Glow'. WTH ? The sharp spray of water worked quite well for the Agave -it was my only victory of the season.
In the front garden, the Lilies continued to be the most affected victims along with the Hellebores and honeydew was clinging to nearby plants as well .Moving into July and August and the damn things stayed. The Man Who Came to Dinner.
In summer I typically park my car on the street a couple days a week to facilitate full access to my tools and garden supplies in the garage. One day I went out in the evening to pull my car back into the garage for the night and when I got into the drivers seat and looked out the windshield and found that it was covered with a fine film of honeydew. As was the entire car-the hood, the windshield, the roof, sticky. Sudden lightbulb moment occurred--street tree is a Crepe Myrtle. One and only backyard tree is a Crepe Myrtle. Both trees are a canopy above the worst aphid infestations in my garden, and the non-aphidized plants that are covered with honeydew. Is there such a thing as Crepe Myrtle aphids ? Research ensued, and yes, in fact the CMs have their very own special aphid , the dreaded Tinocallis Kahwaluokalini. It kind of sounds like something from the cocktail menu in a Hawaiian resort bar, but it explained the coating of honeydew and sooty mold that was pretty much confined to the areas under these two trees. I got out my telescoping tree pruner and cut a small branch from as high as I could reach in the canopy, and there they were-aphids, honeydew, sooty mold.
One of the culprits.
We've had an inch of rain in the last month and it has cleaned things up nicely-the backyard tree is almost devoid of leaves and the street tree in front (which is the variety 'Natchez') hasn't turned yet. I parked my car under it this week and no new honeydew was deposited. But what will happen next year ? Decades of gardening under my belt and aphids in trees that rain down honeydew on the garden and visit the plants below are a new and unwelcome experience. Do ladybugs and soldier beetles ever hang out in trees ? The only option that seems reasonable is to monitor the trees as soon as they start to leaf out in spring and use the trusty spray nozzle on the hose to shoot up into the canopy and dislodge the little devils before they get out of control. I hate to use up my precious water for this , but at least we are in a drought pause and hopefully I can collect enough rainwater to cut down on using city water in spring. I foresee a battle ahead.