How to cause my dog poop surrounded by one place?

I have a 3 1/2 month old Bull Terrier and I have him contained by the backyard and he poops all over the yard..he never poops in alike spot he always has to go to another spot and I dont want him to poop on the concrete with the sole purpose on the dirt. How do I do it so he only poops on the spot I want him to. Is there a spray I could buy to limit where on earth he poops or how do I teach him? Any help?
bring him out to "go" on a leash and bring him to the dirt spot and wait for him to turn.
when he goes praise him and when you bring him out the next time and he go praise him again and keep on doing it until he learns he have to go on the dirt

I do outstandingly recommend training your dog to poop in a specific area. My last dog who died contained by 2002 had a "Potty Pen" and she knew that was where on earth she was supposed to go. We used Shavings in her pen and have a picket fence around her area (of course with an hole for her to go in. When we were training her we would pinch her to that spot go in with her and describe her go potty or if we said hurry up she knew to turn, so then when she went we immediately give her lots of praise and treats.
Answers:    there are sprays but it take discipline on your part. dogs especially pups usually call for to go potty almost immediately after they drink . so put the dog on a leash and walk him to the spot. raising a pup is tough but very rewarding whether you be consistent. its just like raising a kid. be consistent.
You asked this question yesterday.

He's not pooping in the house so I don't see the problem. Just hose the concrete and pick up the poop every day. Use some disinfectant and it won't smell. The longer you resign from the poop and urine out there without cleaning, the more it will smell.
Take him to your specified spot on a leash. Wait til he goes. Praise. Repeat.
If you pick it up every other day, he won't have to verbs finding new spots. Dogs have a tendency, truly, to lean toward specific places for eliminating, but they don't like going into areas that have already be defecated on.
Start taking him out on a leash and take him to the same place every time for something like a week. Then for the next week just go out beside him and monitor where he's going so you can re-direct him. When he goes where he's supposed to compliment him like mad, and/or offer treats. In the meantime formulate sure you've cleaned up and sprayed the other areas or after that week he's gunna go where he desires to again.

put water bottles all over the courtyard, dogs dont wee or poo near their water source. it worked with our dog.
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