There are many many varieties of bare root perennials, but this is a general idea of how to take care of bare root perennials and how to plant them.
RECEIVING YOUR ROOTS
Plant as soon as possible after you receive them, if you can and weather permits. If you need to store them for a short time before planting them, open the plastic bags, but don't let them dry out. Store in slightly moist peat moss in a cold, but not freezing location until you can plant. They can also be placed in pots of soil if planting will be delayed for more than 2 weeks. Use any peat-based potting soil and pots with drainage holes in your pot/container.
HOW TO PLANT
Soak bare-root perennials in water for a few hours before planting (do not soak lily bulbs). The general rule of thumb, is that bare-root perennials are usually planted with the crown (where the shoots meet the roots) an inch below the soil surface. Firm soil gently to eliminate air pockets and water in well. Mark the area clearly since it may be a while before the plant shows itself.
Plant lily bulbs about 6" deep.
Since I am selling so many different varieties, plant all in full sun except astilbe which will do best in part shade - shade, and make sure that it is in a well drained area.
Dig a hole large enough to accommodate the roots without bending them. Work soil around the roots, firm well and water thoroughly.
Can be divided in early spring by carefully splitting a few offsets of the base of the established clump.