Question
should I plant Simplicity or Knockout roses in so. California? i live in zone 10. which one will do the best in my area? I will be planting in front of a 4 foot fence.

Answer
Both roses will do okay in your area but Simplicity has been on the market for a long time but has now got disease problems such as Black Spot. I would go with the Knock Outs as they bloom better and have fewer problems than Simplicity. Keep in mind that Knock Outs can get really tall in your warm climate.