I agree with Bill, you can use fence or restraint system to keep your pet where he’s safest. Keep in mind that dogs won’t be able to do well without love and attention because they are considered as social animals.
Dogs are my life passion.
Read more on my blog: How to house train a puppy
I think a fenced garden gives the dogs a little more privacy and they are less likely to bark at every little thing if they can'y see it. Barking dogs can become a big problem to neighbours.
It is never a good idea to scold your dog. Remember that you want to have a secure and confident dog and you want a good relationship, you just want the behavior to change. As for knocking someone down, he must be jumping... so first teach him not to jump. If he is knocking things over with his paws, teach "leave it" If he is knocking things down with his tail he just can't help that. Dogs "act guilty" when you scold them, but the truth is that they don't know what it is that they have done wrong. They only know that they need to take a submissive stance. Scolding your dog will not teach him, it will only make him cower.
To get back to the original question. I think there a lot to be said for fenced gardens because as well as keeping your dogs in they keep other animals and people out and provide more protection for your dog.