Ground Cottonseed Hull Mulch...
I had never heard of or seen this type of mulch until last year when a friend used it to topdress a new flower bed. I was very impressed with how it looked and felt. So, when i put in a new raised beds for mini's/mini-flora's I used it to topdress this new 8'X8' bed with a layer of about 3-4"'s deep. It not only looks nice, but it is very thick and fluffy and makes an excellent "cover" for the soil and keeps the moisture in and helps to level out fast and dramatic temperature changes in the soil that is so harmful to the rose roots. Also, it is excellent in preventing weed growth because it is so thick. I always install a drip irrigation in each rose bed I put in and this ground cottonseed hull mulch does an excellent job of covering up the hoses and tubes running around the beds making them much more attractive that way as well. As I said, the stuff is fluffy and a creamy off-white color and makes a very attractive finish to the new bed. Lastly, the stuff really stays put well so you don't have it getting blown out and/or strewn around from walking in and working inside the beds as well.
In all, I have been very impressed with this mulch and I get a 40# bag for $17 so it isn't too expensive. That 40# bag goes a long way.
I haven't tried it in a container yet, but I am definitely going to use it this next year when I get my newly purchased bareroot roses in the mail. I am going to use it to top dress the pot and to mound up over the tops of the canes to help them maintain moisture while the rose breaks dormancy. Since this stuff doesn't slide or move around, it mounds up quite well and provides maximum insulating protection for the bare canes until they start growing their brand new foliage.