Worms on the Ferns!

September 16, 2016

Growing plants indoors, be they low-light houseplants, or flowering and fruiting plants you're growing under plant lights, doesn't mean you're going to be free of the kinds of pests and diseases you have to deal with in the outdoor garden. In fact, it's often the assumption of new indoor gardeners that they won't have to deal with any pests, and they're often surprised when pests become one of their first challenges.


Can you see that dark colored caterpillar munching on my little ferns? Drat!!

The reality is that most plants you bring into your home probably bring a few hitchhikers along with them. A seemlingly healthy and attractive plant you purchase and bring home may all of a sudden appear less than healthy. There may also be "evidence" of the critters doing damage.


See all those little "balls"? That's frass; a nice word for pest poop!

Recently, I added some small fern plugs to my Ambienta plant grow lamps. Shortly thereafter, they didn't seem to be looking their best, and I noticed frass (poop -those little pellets you see in the photo) collecting around the bottom of the plants. Yep, they've got worms! Most likely the eggs, or even tiny caterpillars, were hitchiking on the plants, and got to work munching away and growing after I planted the ferns. Caterpillers that chew on plants tend to munch either during the night or day, then retreat back under the soil, or to the center of the plant - making it hard for you to spot them right away. So, you have to look for the frass.

Picking off the caterpillars is the first step to controlling them, as that will help remove most of the critters doing most of the immediate damage. Then, I'll spray these little ferns with a solution of Thuricide (Bt), an organic larvacide that will kill the up and coming caterpillars as they munch on the foliage.

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