The lowest layer in our garden is of course situated in the earth. That's where the bulbs are coming in after the soil has been prepared. In the attached picture of the area of a few square meter I've planted a mixture of Scilla campanulata and Tulipa turkestanica, taking in account the right dephts and relative distances. Afterwards this planting bed has got a good ration of water and the surface is covered with a few centimeters of unsifted compost.