Ask Mr. Smarty Plants

Okay, well, we really thought the Santanas were more interesting. But we'll have a go at identifying what's wrong with your Lantana. Mr. Smarty Plants will tackle any question, whether it's the one you asked or not. Nearly any question. As we told you in our last answer (on the wrong plant) the Lady Bird Johnson Wildflower Center recommends the use of plants native to North America and to the area in which they are being grown. The native lantana we sell at the semi-annual Plant Sales at the Wildflower Center is Lantana urticoides (West Indian shrubverbena). These are red, yellow and orange, sometimes referred to as "calico plant". Most of the plants sold in commercial nurseries are hybrids and non-natives to North America. Some of them can become quite invasive and are regarded as such in places like Florida. However, invasiveness obviously is not your problem, so let's see if we can figure out what is happening to your plants.

Your yellow lantana is probably Lantana camara, cultivar "New Gold." One of the problems with researching the lantana is that most sites are for invasive plants. Even this site, from Arizona Wild Flowers, Gold Lantana, refers to it as one of the 100 most invasive plants in the world. However, one of the pests that are said to infest lantana is the whitefly. It tends to be more of a problem in enclosed areas, being grown as a house plant, or greenhouses. If you bought the lantanas recently, it's barely possible that is the problem, as the infestation may have come with the plant in immature form. The referenced website has some suggestions for identifying and eliminating them. There is always the possibility of aphids attacking your plants; they tend to be more prevalent when a plant is stressed by drought, which goodness know we have had this summer in Texas. And, finally, spider mites may be present. Each of these websites gives some chemical and biological controls suggested for the specific insect. Please read them all the way through and compare with any bugs you can find on your plant. We will also give you some websites with pictures of each beastie. Don't use any controls until you know exactly what you are dealing with. For instance, insecticides will not harm spider mites, but will kill predators of the spider mites, thus increasing the number of spider mites that are actually feeding on the plant.

Pictures of spider mites

Pictures of aphids

Pictures of whiteflies

Now, if you examine all of these and you still don't think you've found the cause, we recommend you just try a bandaid, and see if that's what it takes. Trim off the "diseased" or dead branches, but leave as many green leaves for nutrition as possible. If this means taking a lot of the crown off, go ahead; if the lantana recovers, it will grow back more vigorously than before. Then, give it a little more tender loving care. Even though it is considered drought resistant, if the plants were purchased and planted fairly recently, they may not have developed a very good root system before they were put out for sale. Large commercial nurseries will often "force" blooming to increase sales appeal, and the roots may not yet be able to take care of the plant's needs, once it gets into the ground. Don't fertilize it, over-fertilizing is one of the things that attracts aphids. Put some shredded hardwood bark over the roots for cooling and retaining moisture, and give the plants some regular deep drinks of water. As tough and well-adapted as this plant normally is, we feel it will rise and bloom again, maybe not this summer, but surely next spring.