The cat behaviorist might be right. But I did it the other way in our small house. I let the cats meet & then I opened the cat carrier door. I closed the bedroom doors & basement off for a few weeks. I brought up a litter pan that I cleaned to the bathroom. After two weeks, I opened back up the basement & put the pan back in the basement. Someone was not getting his butt into the pan when he peed. We opened the other doors a week later. I put out extra water & food bowls. The cat that was scare & hissed was the new 2 year old girl. It took her 6 weeks to give up & let my 11 years old boy love her. Love her he did. He now licks her on top of her head. She loves that & can't get enough! For us, a cat was better than a kitten. One tip! I made extra time to play with my boy everynight. I sat on the floor & played with him, combed him & gave him treats, vitamins or catnip. New kitty watched us & by the third night she wanted to join us. I sat on the floor for a month. PS, new kitty did not like our carpeted scratching post. She liked one of the laminated cardboard ones to scratch on. That was an easy addition to save the furniture. Her favorite toy is a thin bamboo stick. She chases the tip on the carpeted floor. They did not like playing in a box that I cut a small hole for a paw to come through. I thought for sure the box would be a great play time for both of them.

Not necessarily so but yes, you could be headed into a problem. Scent is a big thing for cats and the new one may start marking because he smells marks on the rug already. It's probably going to be dependent on the cat. Why is your cat peeing on the rug? You didn't mention him having medical problems so that leaves a behavioral issue. What have you used to clean your rugs? If you can still smell pee in the house (unless its from a brand new pee episode) you haven't used the correct cleaner. I've learned the correct cleaner is a necessity. You've got to get a good enzyme cleaner designed for pet urine. Soak the soiled areas and you might have to go down to the padding/floor boards if it was deeply soaked. Sometimes you have to do it twice. It's a chore but try to eradicate any sign of odor to see if you can correct it if he's having a behavioral issue. (They sell black lights that you shine on your carpet in the dark and urine spots show up to help you find the places needing treatment). Does he seem lonely for a playmate? He might be happier living out his days as a solo cat if he's elderly rather than being introduced to a new guy. That's a consideration, too all dependent on his personality and age. I'd personally try to get his problem corrected before bringing in a new one. Pee smell in the house is awful! Remember, a new guy is going to cause him some type of stress which might exasperate the situation.

I usually cut mine back about this time once the blooms fade...maybe to 6 or 8 inches tall. They put out new growth pretty quickly. Now if your stalks are limp or wilted, that's a different issue: maybe too little water or something. Mine is perennial, dies out in late fall. I remove the dead stuff in the spring, and we start all over again with new and usually larger plant. You're in the annuals forum, you know. You might pop over to the perennial forum and you'll see a bunch about napeta or catmint... Good luck with yours!

I have a couple/three catmint/Nepeta planted in full sun the past 5 years and do nothing to them. My lawn guy hasn't buzz-sawed them but they've pretty much tolerated whatever New England can throw at them (i.e., 6 ft. of snow a couple years ago; zero snow this past winter). You state, 'the stalks are not standing tall, but falling over the sides of the pot and the blooms are fading.' My guess would be either some parasite has started chomping on them or they're root-bound in the container(s) and need to be in the ground. In my experience, if the roots are crowded and have nowhere to spread, the plant is going to suffer. Good luck; hope you discover the problem soon.