Ask Mr. Smarty Plants

Tagetes lemmonii, Copper Canyon daisy, does not appear in our Native Plant Database. From other sources, we have learned that it is native to Arizona and Sonora, Mexico. Our database is a work in constant progress, and this plant apparently has not made it there yet.

We found one website Hill Country Native Plants with a little information on it. This USDA Plant Profile on the plant shows it as native only to Arizona. We did find a good article from the Native Plant Society of Texas A marigold for fall gardens. 

To sum up what we learned about this plant, it needs full sun to thrive, good drainage and an alkaline soil. It is a "day-length" plant, meaning it blooms the most heavily in the shorter days of Fall, and with some blooming in early Spring. 

You did not say if this was the first year for your plant in your garden. If it has grown well in past years, and is not doing as well this year, there must have been some change in the environment of your garden to affect it. If you had it in the ground last Winter, we know that your area had some very abrupt and unusual low temperatures. This plant is really a desert plant, and will freeze back, but ordinarily, if it is cut back, it will return in the Spring. The other point I would like to make is that Spring Branch, close to Houston, really has more East Texas acidic soils than western alkaline soils. And you have more rain than we have, for instance, in Central Texas or West Texas, so if the drainage in your bed is not good, the plant may be objecting to water standing on its roots. 

Pictures of Copper Canyon Daisy from Google.