There is a natural garlic based yard spray called mosquito-less.
NOTE I DO NOT SELL THIS STUFF, I had a heck of a time just finding enough for my own needs last summer when I made the mistake of telling people about it.
It said on the bottle that it worked for ticks also so we tried it on our yard.
We live on a 80 acre homestead in the sticks with a pond behind our house so I was really worried about mosquitos.
I sprayed the front yard and the dog kennel with the stuff and it REALLY WORKED.
I actually sprayed it on myself as a test and went for a walk in the bush in july.....no mosquitos and no ticks....mostquitos were around but they kept 2+ ft away and if they did land they IMMEDIATELY flew off.
To put things in perspective, walking without any protection would have led to 20+ ticks and a gazillion mosquito bites in the matter of a few minutes..
We have 2 large GSD's and we were pulling lots of ticks off them every day even with the tick stuff you put on thier necks.... As long as I sprayed the yard every 3 weeks we had no issues with either.
Here is the website
http://alexmilne.com/mosquitoless.html
I also know that ticks dont like the garlic stuff as I pulled a few off and put them on a piece of cardboard inside of a circle i made by dipping my finger in the garlic stuff.... They kept trying to get out of the circle but when they would hit the line of dried garlic stuff they would turn around and head in the other direction....frankly it was kind nice to torment the creapy crawlies for a change rather than the other way around.