Colorado frost dates: O

City	Last frost	First frost	Season	Zone
Oak Creek	Jun 14	Sep 11	89 d	5a
Ohio City	Jun 21	Sep 5	76 d	5a
Olathe	May 2	Oct 8	159 d	6b
Olney Springs	May 2	Oct 8	159 d	6a
Ophir	frost any month			5b
Orchard	May 6	Oct 6	153 d	5a
Ordway	May 2	Oct 8	159 d	5b
Otis	May 8	Oct 6	151 d	5b
Ouray	May 18	Oct 4	139 d	5b
Ovid	May 7	Oct 6	152 d	5b