A tulip pot left outdoors needs a way for rainwater to escape. Before adding compost or bulbs, check the drainage holes and decide where the container will stand.
A hole can be present but ineffective if the base is pressed against a flat surface. Avoid an outer pot or saucer that turns the planting into a reservoir during wet weather.
Follow the bulbs' planting information
Depth and spacing depend on the bulbs and the planting plan. Read the supplier's guidance instead of copying a depth from a photograph with no scale. Allow for the finished compost level, not just the depth of the empty pot.
Keep the label with the container. A pot of bare compost is surprisingly easy to mistake for an unused one before growth appears.
After planting, monitor moisture and drainage through the local season. A sheltered pot under an overhang receives different rainfall from a container in the open. Watering both on the same timetable ignores the main difference between them. Check each pot where it actually stands, especially after a prolonged dry spell or several days of rain.
Related reading: Planting Tulips in Borders and Containers.