There is a LOT of information left out in your description which is necessary to make any suggestions. How do they look "paltry"? Did the foliage on the plants begin to show diseases and fall early (summer)? I know the weather across much of Texas has been Hades on earth for the past few years and rain hasn't come in sufficient or even near normal quantities. Have you supplied enough water to supplement the lack of rainfall? Are the plants growing near walls, patios, concrete side walks or a drive way where they will receive a lot of reflected, radiated heat? Might you be able to photograph them to show the conditions in which they grow and what they look like?

They could be severely water stressed. They could be severely heat stressed. They could have been accidentally exposed to chemicals like weed killers. You could have insect issues which are causing them to suffer to the point of looking awful. They could be suffering from disease issues which also could cause the problems. It's also possible someone has damaged them with a string trimmer while edging the garden. Hopefully, photos will help. Kim

SE Texas is the worst part of the state for blackspot disease. which causes leaves to yellow behind dark spots and fall off. Is that what has happened to your foliage? This disease is in all rose gardens in your area. It is controlled by regular use of a fungicide, or by replacing with varieties that are resistant. Most varieties at the garden center are not resistant, but people here can advise.

When I lived in that area, many roses defoliated during the worst heat of July & August. I kept up the watering, fed them at the beginning of Sept. & enjoyed a new flush of leaves & blooms when the weather moderated. Usually, in September, the nights start to get cooler & give the plants some relief.
Fall blooms were often the best of the year in that climate. And once the roses recovered they were beautiful into December.

Defoliation is the plant shutting down because of stressful adverse conditions. Sometimes it's only one stress that causes it, but more usually it is a combination.

So for example, a rose being stressed by a lack of water will not need much pressure from black spot to start shutting down. Similarly, a rose stressed by an untreated black spot infection will not need much pressure from a lack of water to start shutting down.

Unfortunately, if the shut down continues for too long it can be fatal. Roses and other plants are not immortal, and they do die if conditions are adverse enough.