My vet confirmed that garlic in small doses is a good all-natural tick repellent. I give my boys Solid Gold garlic bagel dog treats in the summer and have been able to cut back on the amount and lengthen the time frame that I have to use front line. My little guy does not tolerate front line well, he gets lethargic and throws up for a day after I put it on him. Now I use 1/2 a dose on each dog and reapply every 6 weeks instead of 4. This works well in conjunction with the garlic treats.
I wouldn't feed my boys a whole head of raw garlic thats for sure, but sprinkled sparingly into food or baked into treats does help with ticks. I am in New Hampshire.... ticks are almost year round and more than 50% have lymes disease now.