I can’t help from direct experience with TX heat, but some general comments.

-Type three prune plants seem to do best in hot areas from what other gardeners in the SE quarter of the US say.

-Mulch well around them to help keep moisture even. Don’t let them dry out, but they don’t like soggy soil, either.

-They do well with the same fertilizers used for roses.

-If the vines die back, don’t be afraid to cut them back. IME they will regrow readily.

-Flower color may be better retained and fade less if they get some shade during the most intense sun.

Your blue flowered plant that is similar in shape to Princess Diana may be Rooguchi. It has bell shaped flowers and is a rich blue-purple. IME it doesn’t climb well, so I grow it up the center of an obelisk. But if you post a photo of a bloom, you may find someone who recognizes it.

I would love to see updates on how yours do so that other folks who want to grow clematis in your area see what worked or didn’t work for you.

Thank you! I will be sure to update. I had looked into clemantis before, but generally felt they dont do well here. I picked these up as they were at the antique rose emporium and thought maybe they will do ok. They are just starting to come up, I will be sure to mulch well and try to keep the roots cool.

Cool roots is less important than even moisture, so check moisture in the soil every so often.

There are several species of clematis that are native to TX, so I would definitely consider any selections of these or hybrids that include them as a primary parent: Clematis texensis (obviously :-)), C. crispa, C. pitcheri and C. drummondii.

Also, viticellas and their primary hybrids are also extremely tolerant of heat and would be good possible choices as well.

Proper irrigation will help any of these to thrive in your climate and flower more heavily.

The old 'Jackmanii' cultivar is a workhorse in north Texas alkaline clay and heat (in group 3 as NHBabs suggested). Nice late spring/early summer show, but only spotty reblooming of a few flowers at a time.... though rarely does have a second less intense flush later in the season. Divisions banked in spots with afternoon shade have survived years on rain water alone. Others we have in full sun thrive once established with only the weekly deep watering the lawn gets as needed. Have not had our C. texensis hybrids as long, but they've also done well with similar treatment.

They should be able to handle your Pearland soil and heat, though don't know if the higher humidity and rainfall makes C. wilt resistance a more significant consideration for your area than in drier parts of the state. 'Jackmanii' is not considered resistant.

IME, clematis wilt is far less likely to occur on any of the early blooming species clems (Pruning group 1) and also on most of the later blooming (Pruning group 3) species and hybrids. Wilt is far more likely to occur on the large flowered hybrids (aka Pruning group 2). Although considered a group 3, Jackmanii (and the jackmanii hybrids) are quite susceptible, as they are large flowered hybrids.

Often, adequate deep root watering can offset the likelihood of wilt, as will burying the root crown 4-6 inches.

Rekha, one of my best friends lives in Pearland - he gardens but isnt the fanatic I am. You should do fine with clematis - I have a bunch of them and they were just beautiful last year. A lady named Jeanne from Conroe who doesnt post anymore had THE most beautiful clematis! Wish she was still around, a wonderful source of knowledge. IMaybe you can find some of her older posts on the Clematis forum. I read that until they get established - it is good to cut down to about 6" or so of all clematis - this makes them put up more shoots. I have done this and found it to work. I have a bunch in pots that I need to plant - I have mine in sun and mulch them. Ernest Markham, H.F. Young, Mrs. Chomondeley, Monte Cassino, Niobe [one of THE best reds] are favorites. They are really tough, mine come back yearly. When they bloom, they are glorious! Go to the Clematis forum on this website - lots of pretty photos. Dont be afraid of them, just plant them, mulch, keep watered and they will reward you! I have some lovely photos, will try to go back to last spring and post some.

Judith