Thanks for your question. Yes; it is safe to plant these perennials now. They are very hardy, and will survive the winters. Ferns and hostas will lose their leaves, but the roots will survive. Andromedas (pieris japonica) are woody plants, and have bark to protect them. You can look up the historical low temperatures for your area by typing in "USDA zone ________ (where the blank is your zip code.) We have already passed the last frost date for this year. Good luck!