Since your Amaryllis are growing in pots, as soon any danger of frost has passed, go ahead and transplant them into your garden. Cut the leaves off, but leave enough that the cut surface will be slightly aboveground. If they are the hardy Amaryllis (Hippeastrum x johnsonii) as I suspect, there is no need to dig them each year. Hardy Amaryllis can be planted outdoors in plant Zones 6a - 11. A liberal covering of a good mulch should provide any winter protection that they need. While the information in the article at the following Web site is directed toward South Florida, most will be of value to you: Amaryllis.