Hunger and cleanliness stats should increase every hour as long as they are fed and cleaned. It's tough to say how often but every hour isn't necessary. I don't think it stacks stats the more you do it in a day... But there's also no telling when it expires since the XML doesn't give any more information then what's provided on the wiki page. These pixel bees are not like real life bees and won't care about decorative flower bushes. The classical music bit is indeed a Sims 4 thing. But I won't judge... you can shower those bees with flowers and music if you want! ;)
Here's more info I've gathered from other sources:
Game tips mention Smoking the hive is beneficial. Smoking the hive not only reduces the chance of being stung or attacked by the bees but also increases happiness by 15%, also increases hunger. The smoke last for 4 hours
A sign of a happy hive- Bees will buzz around in a circle VS wildly swarming.
Once or twice a day: Smoke Hive, Clean Hive, Feed bees. Harvest when available.
According to someone who did this every sim day, they started to get outstanding honey within 2 sim weeks. (residential lot)
You can tend to bee hives on a community lot to make it easier since hives on a community lot won't go below a happiness score of 72/Very Nice quality.
Another option is to essentially cheat and download a tuning mod. It removes the need to clean&feed keeping the hive at 100 happiness score always= perfect honey 100% of the time
http://modthesims.info/d/506123
You could poke at it with S3PE to tune it.
edit to add: Typing on a smartphone is very slow. I apologize for some of the repeat info here. :D This thread is useful for me too since I haven't had my sims beekeep in a long while but will be doing so soon.
