Yup...

There's NO way to "cover up" the smell of flowering mj... I agree with the others here that the only way you can effectively deal with it is to remove the odor by constantly scrubbing the air with a carbon filter. To do this requires a relatively decent inline "can style" fan which is used to constantly pull air from your grow room through the carbon filter and the odor is absorbed. The output of the scrubbed air can be exhausted out of the grow room with duct work. Good room ventilation also helps to control odor and when combined with filtering will completely control odor.

Scented items like cigarettes, candles, air freshener sprays, incense etc. can't cover up the smell. They may help mask things slightly but the odor will still cut through, especially to people who don't have a smoker's nose.

The only safe way to grow is to get this completely under control. Find a filter and setup that will work for your grow and you'll have peace of mind.

Good Luck!