Puppies are inquisitive and adventurous, which is why that gate is such a source of intrigue. For his own safety, it’s essential that your puppy knows not to jump that gate. Fortunately, you can use his love of play and human contact to show him the error of his ways.
Give your puppy plenty of exercise and mental stimulation. A bored puppy with energy to burn is more likely to jump a gate than a worn out, mentally satisfied pup. Regular walks and energetic play sessions are a great way to keep your pup stimulated.
Obstruct the gate. Use potted plants, garden furniture or whatever you have on hand to block his view of the gate from the house. If he can’t see the gate, he’ll focus his attention elsewhere. This is one of those rare times when a puppy’s short attention span is a benefit. Obstructions are also handy if your pup needs a running jump before scaling the gate.
Supervise all visits to the garden. Don’t let him out to wander about or for potty breaks unaccompanied. If he’s given unlimited time to explore without distraction, he’ll eventually arrive at the gate. Because a puppy doesn’t have the same hazard awareness as an adult dog and because he’s still learning about his environment, curiosity will get the better of him.
Walk up to your dog with a treat in your hand. Move the treat toward his nose, then upward. He’ll follow the treat and will eventually position his body to get a better sniff. As he follows the treat, say “sit.” As soon as he parks his posterior, release the treat. By saying “sit,” then releasing the treat, you teach him that the action of sitting in response to the command has a positive result.
Repeat this process until he adopts the sitting position right away.
Perform the command using just your hand movement, without the treat. With sufficient repetition, sitting becomes its own reward.
Put your pup on a long leash and let him explore the garden.
Give him verbal praise for as long as he isn’t investigating the gate. Implement a small exclusion zone around the gate into which he must not enter.
Gently tug the leash as soon as he goes near the gate and cease all verbal praise. This diverts his attention from the gate back to you. By ceasing the praise, you show the dog that going near the gate results in a positive stimulus being taken away. The leash is primarily a distraction tool, but also serves as a safety net if your little Houdini makes a break for the gate.
Give the sit command. If he ignores you, tug the leash. As soon as he obeys, walk over to him and lavish him with praise. This teaches him that investigating the gate results in physical restraint, a negative consequence.