Just wondering what other landlords in Colorado are doing in regards to the Devil's Lettuce?  

To me,  no smoking in the lease is pretty obvious that it should cover this as well, but apparently it doesn't with a current tenant.   

Do you have it listed in the main body of the lease when discussing smoking in the unit or is it an addendum as it is a specific issue to Colorado or other states where it has been leagalized?  

What about growing it?   Do you have something in the lease stating it is forbidden on the property regardless of it being legal in this state? 

My lease says, in a section on "Use": "Tenants with not smoke or allow smoking of any substance inside the Premises."

It also says, "The use, possession or sale of any illegal druq on the Premises ..." is prohibited. Possession covers growing, but I suppose we could say "drug or other substance that is illegal under state or federal law."

@Joe Zupancic I apologize that I am so late in responding to this. No smoking is no smoking. It doesn't matter what is being smoked unless for some odd reason your lease only prohibited tobacco smoking. It is a violation of the lease to smoke anything. You need to issue a "Demand for Compliance or Possession" The tenant has 3 days to correct (stop smoking). If they stop before the 3 days then you are done. If they stop and then at some point at a later date (after 3 days) smoke again then you issue a "Notice to Quit for Repeat Violation". They either then move or are evicted.

That said, it can get complicated and my advise is that you need an attorney to help you with this. Go to the local court house and ask who (what attorney) does most of the evictions in your county. You then go and hire them to help you with this. 

This really gets hairy if the tenant fights you in court. You then have to prove to the court that the tenant smoked in the unit and then prove that they repeated the violation after your first notice. This is where you need the attorney because they will guide you on what is needed for "proof".

Having a non-smoking unit is perfectly legal and you avoid the whole discussion about what was or wasn't smoked.

Hope this has worked out for you. If you have more questions post back.