There are 19 Diglett to find in the Fields of Honor.
Alolan Diglett #1

This Diglett can be seen while talking to the Diglett Trainer (no not the one directly next to him!). Just cross the bridge and turn right into the flowers.
Alolan Diglett #2

This Diglett is just outside the Master Dojo. If you are coming up the ramp turn left. It’s in front of the rock.
Alolan Diglett #3

Just before the Soothing Wetlands there is a hill with a tree at the top. The Diglett can be found at the tree’s roots.
Alolan Diglett #4

The Diglett can be found between the bridge and the ramp to the Master Dogo. It is hiding with some pebbles.
Alolan Diglett #5

If you turn right at the Diglett Trainer you’ll find the Diglett near the edge of the cliff before reaching the Pokemon Den.
Alolan Diglett #6

This Diglett is hidden in some grass at the top of the hill. The hill is just before the river entrance to Courageous Cavern. To get to this spot head left from the Diglett Trainer, following the river.
Alolan Diglett #7

If you head down the hill from Diglett #6 (just before the river entrance to Courageous Cavern) and head towards Armor Station this Diglett is hidden between two patches of grass.
Alolan Diglett #8

This Diglett is near Diglett #5. Just head right from the Pokemon Den. It is on the grassy slope before the sand on the beach by two pebbles. Otherwise, exit from Armor Station and follow the beach until you reach the grassy slope. A little bit further down on the sand is Diglett #15.
Alolan Diglett #9

The first Diglett you’ll encounter. No other Diglett will spawn until you’ve interacted with this one. It can be found in front of the bridge that leads to the Master Dojo.
Alolan Diglett #10

This Diglett can be found hiding behind a tree near the cliffs edge. To find the tree go up the ramp in front of the Master Dojo and turn left. It is by the tree closest to the paper lantern.
Alolan Diglett #11

This Diglett can be found hiding behind the Berry Grocer. To find the Berry Grocer go up the ramp in front of the Master Dojo and turn right.
Alolan Diglett #12

This Diglett can be found hiding in the soil belonging to the Ingredients Seller. To find the Ingredients Seller go up the ramp in front of the Master Dojo and turn right. It is the plot of land next to the Berry Grocer.
Alolan Diglett #13, #14

When you exit Armor Station there are two trees to your right. There is a Diglett by each one.
Alolan Diglett #15

When you exit Armor Station follow the shoreline to your left until you reach the grassy slope. The Diglett is hiding in the sand by the grassy slope and water. Further up the grassy slope is Diglett #8.
Alolan Diglett #16

From the Diglett Trainer cross the bridge and immediately turn right. Follow the cliff until you reach the Diglett hiding near the top point of the cliff.
Alolan Diglett #17

Go up the ramp in front of the Master Dojo and turn right. Ride past the Berry Grocer and Ingredients Seller up the hill towards the tree. The Diglett is hiding by the tree.
Alolan Diglett #18

Exit Armor Station and turn right. Walk towards the stacked wooden boxes. Look through the gap between the boxes and the station to find a Diglett.
Alolan Diglett #19

Exit Armor Station and turn right. Walk along the narrow grassy path along the shoreline until you reach the flower patch before the Berry Tree. The Diglett is hidden well within these flowers so look carefully.