It may be alittle transplant shock... Have your temps been high? If so you might want to shade them during the hottest part of your day for awhile until they perk back up. Like put plastic outdoor chairs over them. But I do realize you have 20 of them so that would be rough. Keep them well watered... Did you give them any granular fertilizer? I just did that to my starting the second year double KO's and they did not like it very much at al herel. I do not fertilze first year roses at all...

A 15-gallon pot is likely to be 18" across & nearly as high. If concerned about water stains from a pot standing on deck or balcony, you might pick up pot feet as an alternative to a wheeled dolley. They fit under the bottom rim to raise the pot, run a couple of dollars each & you'd need four for a pot that size. Usually found with the pots outside, as they also keep a pot from freezing to a bottom surface & cracking. Often use them & just slide a saucer beneath for water to drain to which can be emptied & removed in between waterings. Might consider using a few inches of mulch atop the soil to keep it cooler & delay moisture evaporation (kept from touching the stems) & pine straw for that is fine. Also keeps soil from splashing out in watering or rain. The potting mix you used contains slow-release fertilizer, but as others have noted, you'll need quick-release fertilizer for pots as well. The rule of thumb is "weakly, weekly" meaning fertilizer diluted in water at 1/4 the concentration on the bottle for monthly feeding, given weekly by pouring on soil already moist. Some of the fertilizers are very salty & can build up a residue on top of the soil & interior of the pot. Prefer fish emulsion myself. What a romantic gesture from your boyfriend! Sounds like he's a keeper, just like your rose... Here is a link that might be useful: General soil capacity pot sizes

I did live in the burbs in Houston for almost a decade, and if I see your gardening area correctly, the rose is planted right next to a cement slab. (And the weepholes in the brick wall in back of the rose?) The problem is, or at least may be, that the slab may be affecting the pH of the soil. And that pH may be affecting nutrient uptake by your roses. (Also there may be some chemical treatments done to the perimeter of your house before you moved in. First, call the Texas County extension agent and ask him or her about getting a soil test for that specific soil (forget about any suggestions that you should take samples from all over your yard, that's for grass growers). Also ask that the test check for nutrients in the soil.

One year, I lost 35 roses to RRD. I'm down to losing maybe 1 a year because I notice the symptoms earlier now. Pink Double Knock Out is the best KO, I think. I have a whole hedgerow of them, and they do great without feeding or spraying or even irrigation! La Marne looks beautiful! Wonder why I don't have that one? I have an Earth Kind bed, and in the past few years, I've been favoring Kordes roses over the Buck roses that made up most of the Earthkind list. It could be that I've been buying the Kordes roses from Palatine and they come to me much more mature and grafted to multiflora, where the Buck roses come from Chamblee own-root, and much much smaller. They struggle to get established in our harsh conditions, where the Kordes roses grow like crazy. As a matter of fact, I have a problem right now with some of the Kordes Fairy Tale roses. They grew way larger than expected---catalogs say 3-4 feet, mine are 9 feet tall and wide. They bloom constantly, even now, in October, and the foliage is awesomely clean and green! Too bad I have to move them so they don't completely cover my front entrance! I'll look into La Marne too, because those photos Patty posted are really a great endorsement.