The lawn has craters. The flower bed is a trench. It started somewhere around 9 or 10 months old and it has become the first thing your dog does when the back door opens.
Why it started, and why telling them off does nothing
Digging pays instantly and it pays every time. Cool soil, interesting smells, roots that move, and a whole activity that requires no one else. Nothing you say afterwards competes with that.
It also arrives in adolescence for a plain reason. Your dog now has the size, stamina and independence to entertain themselves, and an empty yard is the easiest place.
Punishment-based approaches are associated with fear, avoidance and defensive aggression, and they do not remove the payoff. A dog told off for digging usually digs when you are not watching.
First, remove the unsupervised rehearsal
For the next 2 weeks, your dog does not go into the yard alone. Every trip out is with you, on a leash if the holes are winning.
This is not forever. It is how you stop your dog getting 20 more repetitions of digging while you work out what the digging is for.
Today: give the digging an address
Pick one spot your dog already likes. A corner, a shady patch, wherever the deepest hole is. Loosen the soil there, or set down a sandpit or a large tub of sand.
Bury 3 things while your dog watches. A chew, a stuffed toy, a handful of food. Do not hide them well on day 1.
Let them dig it up and leave them to it. Say nothing. The behaviour is not the problem, the location was.
Do that once a day for a week, burying things slightly deeper each time. Then start seeding the spot before your dog comes out, so it is already worth checking.
Then make the rest of the yard boring
Fill the old holes and put something physical over them for a fortnight. Chicken wire under a thin layer of soil, a paving slab, or a pot.
Take your dog past a filled hole on the leash and pay them for walking past it. Do this 4 times. Walking past is a behaviour you can reward, and digging is not.
If they head for the wrong spot, walk them to the right one without a word. Every silent redirection is worth more than a told-off.
The two things that are usually underneath it
Sniffing. A dog who digs is often a dog whose walks are brisk and short. Let them sniff for 10 unhurried minutes on one walk today and watch what happens in the yard afterwards.
Chewing. Adolescents chew and dig for many of the same reasons. A daily chew, indoors, in a settled spot, takes a surprising amount of pressure off the lawn.
Safety note
Some digging is not entertainment. Digging frantically at a door when you leave, or until the paws bleed, is telling you something else. Sudden behaviour change warrants a veterinary examination, and pain often presents as a change in behaviour. Book that examination, and speak to a qualified behaviour professional.
Today's version, in one line: loosen one corner, bury 3 things while your dog watches, and cover the old holes.