Walk the boundary as if you were the puppy
Get down to puppy eye level and travel the whole perimeter slowly. The gap under a gate that looks trivial from standing height is a motorway to a ten-week-old, and puppies test fences at their weakest points: loose boards, a dip where soil has washed away, the space beside a gate post. Push on every panel, check for digging spots along the fence line, and fit mesh or boards over any gap a puppy's head could fit through — where the head fits, a determined puppy often follows. Make sure the gate latches shut by itself or is kept latched by habit, because a garden is only puppy-proof while its exit stays closed behind every visitor and delivery.
Remove the poisons and the swallowables
Gardens concentrate exactly the substances that harm curious puppies. Slug pellets, weedkillers, fertiliser, antifreeze stored in sheds, and rat poison are all dangerous in small amounts, and several common garden plants are unsafe for a puppy to chew, so check what is growing in your beds against a reliable list and fence off or remove anything risky. Lock chemicals away rather than leaving them on a low shelf in an open shed. Sweep up the small hazards too: stones a puppy might swallow, broken plant pots, stray screws from the latest project, and the fat-ball that fell off the bird table all end up in a puppy's mouth during an unsupervised minute.
Make water, drops, and climbing safe
Ponds, even shallow ones, are a real risk to a puppy who falls in and cannot climb the slippery edge, so fence or cover them until the puppy is older and has learned the garden under supervision. Block steps down to lower levels, gaps in decking where a leg can slip through, and any raised area a puppy could tumble from. Check trampolines, stacked garden furniture, and fire pits for the same reason: the hazard is rarely the object itself, it is the puppy meeting it at speed, mid-game, with no adult watching. A secure cover on water butts and bins removes another set of quiet risks.
Set the garden up for the jobs it must do
A puppy-proof garden also has to work as a toilet and training space, often in the dark and rain. Keep one clear, easy patch for toilet trips so you are not crossing the whole garden at night, keep a lead by the back door for the early weeks, and use a long line if your puppy treats the garden as an escape rehearsal. Secure the compost heap and vegetable beds if you have them, because puppies dig enthusiastically in turned soil and some crops, including onions and grapes on the vine, are unsafe for them to eat. Outdoor lighting along the route to the toilet patch makes night trips safer for you as well as the puppy.
Supervise as if the proofing were a draft
Every puppy finds the one thing you missed — the loose stone in the border, the fascinating hole behind the shed — so treat early garden time as supervised time, and watch what the puppy actually investigates rather than assuming the audit caught everything. When you spot a new hazard, fix it the same day and tell everyone else in the house what changed and what the puppy is currently obsessed with. That shared awareness is the point of KinsLe Family Sharing: the puppy's care information sits where family members who help can all see it, so the person letting the puppy out at dusk knows the same gate, pond, and digging warnings as the person who proofed the garden.