Ask Mr. Smarty Plants

Mr. Smarty Plants thinks you are on the right track with your questions about soil pH and sun.  Salvia roemeriana (Cedar sage) likes alkaline soils with a pH greater than 7.2. It is one of several plants that have evolved to grow in the shade and leaf mulch of junipers. It can become stressed and stunted in continuous full sun and has a hard time perpetuating itself under deciduous hardwoods. I don't know the specifics of your situation regarding sun or shade and the presence or absence of deciduous hardwoods, but I strongly suspect that the soil pH in your area is lower than 7.2.

Another obstacle you are facing is that Collin County, wherein Lucas is located, is outside the normal range of distribution for Salvia roemeriana. This link is a map showing its normal range according to the USDA: County distribution of Salvia roemeriana.

Now, just because a plant is outside its normal range and doesn't have perfect soil and sun doesn't mean it won't grow. As you say, yours are quite happy and blooming. But, when you combine all these factors, a plant may not perform to its full potential.

Here are a couple of suggestions:

1. Quit your job, sell your house and relocate to an area where cedar sage is found naturally. OK, Mr. Smarty Plants doesn't really think you are willing to move for the sake of a plant, but it is an alternative.

2. Try growing your cedar sage in containers. In a container, you can determine soil pH by your selection of growing medium and you can place the container in a favorable light setting. Here is a how to article on container gardening with native plants.

Finally, here is a picture of cedar sage in bloom. You can see why the hummingbirds and butterflies like it.

Salvia roemeriana