Yes you can. I do this every year. You can either sink the plastic nursery pot into the ground and hide the rim with some mulch or dig a hole and carefully remove the budded tulips from the container and settle them into the garden soil. Firm the soil a bit with your hands to keep the newly planted tulips from falling over. Once the tulips are done blooming you can pull them up or move them, pots and all, to and out of the way spot so the foliage can ripen and fade to make next year's flowers.  Daffodils will return year after year from nursery purchased plants more easily than tulips so don't feel bad if your tulips fail to make an encore display next year. Some gardeners just consider then one and done bloomers and get fresh plants each spring or plant fresh bulbs each fall. Keep growing, Marianne Binetti