&Tradition Collect Planter SC43 Space Copenhagen 2020 Instructions Manual page 6

Step 5
Place the self-watering insert (C) into the sleeve (B),
Make sure that the lid is kept above the top edge of the
sleeve, so it's not covered with soil.
Step 5
Place 4 cm of clay pebbles in the bottom of the sleeve.
Step 6
Add soil and a plant untill the sleeve (B) is covered, the lid
of the self-watering insert (C) should still be uncovered
and free of soil.