Roots, Shoots, Fruits & Flowers: Master Gardener Class, Orange Dog Caterpillar, & Ailing House Plant


Figure 1. Master Gardeners at their Spring Garden Forum in 2019. Photo by Jimmy Earl Cooley.

The holidays are coming up very soon, and then we will be in a New Year. With a new year, comes new opportunities. One opportunity to consider is enrolling in a Master Gardeners class starting on January 2, 6 PM, at the Sheriff’s Training Center, 412 Bolivar Bishop Drive, in DeRidder, LA. The cost will be $160 for 12 weeks of classes. Master Gardeners are AgCenter Volunteers who receive horticultural training in weeds, insects, plant diseases, turf, vegetables, ornamentals and other related topics.


Figure 2. An orange dog caterpillar usually found on citrus trees. Photo by Carolyn Applewhite.

Carolyn sent a clear picture with this question, “I found 4 of these caterpillars on a small satsuma plant today, do you know what kind it is?”

This caterpillar is an orange dog caterpillar, and it resembles bird droppings. This caterpillar becomes a beautiful giant swallowtail butterfly. Once gardeners understand that this caterpillar becomes an attractive butterfly, they tend to tolerate the slight damage it causes to citrus foliage.


Figure 3. Dieffenbachia, a house plant, with dead spots. Photo by Pam Archer.

Pam of DeRidder sent her questions about a house plant, “Can you please ID this plant? And what is wrong with it, besides needing repotted? “

AHA consulted with Dr. Sara Shields, a Horticulture Specialist with the AgCenter, and she shared some useful comments, “Yes … that’s a dieffenbachia.

Houseplants can be rather fickle if the conditions are not right. The main issue I notice is that the humidity in the house needs to be much higher than what people usually experience. The homeowner can use a spray bottle and mist the leaves from time to time to increase the humidity in the immediate area. A light spray will do, no need to drench the leaves. While the leaves should be lightly misted once or twice a week to increase humidity, the homeowner should take care to apply water at the soil level and not on the leaves or stems.

Spots like that make me think of either a water issue or nutrient issue. Houseplants are typically not watered thoroughly which can result in salts building up on top of the soil in the container. I’d look for those salts and remove if present. Take outside and drench thoroughly to encourage movement of salts out of the drainage holes. I’d also look at roots to see if rootbound or if the plant needs to be repotted. Houseplants aren’t typically fast growers, but they do need to be bumped up every now and then. I’d also question fertility regimen. Several fertilizers make a houseplant food that can be used, or regular old Miracle Gro can be applied once every week or two.”

If you want to contact Roots, Shoots, Fruits and Flowers, please send your questions and pictures to Keith Hawkins, Area Horticulture Agent (AHA), 337-463-7006 or Also, you can be on the “green thumbs” email list by emailing your request to the address above.

“This work has been supported, in part, by the USDA National Institute of Food and Agriculture, Renewable Resources Extension Act Award, Accession Number 1011417.”

12/16/2019 9:50:43 PM
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