Although I feel comfortable with most mowing and some landscaping questions, I was not sure about this and was looking for some input. I've got a cust who wanted her yard dethatched. I had her on the schedule next week to do so and then she gave me a call yesterday. She has fertilizer applied from another company, and on the invoice it said not to dethatch after this fertilizer application. I couldn't really come up with a reason why not to. I figure maybe wait another week and then dethatch? Again, bear with me because I don't know that much about fertilizers and weed control yet. Basically what I'm wondering is if its ok to dethatch, and if not why?