New Jersey has the United States Department of Agriculture hardiness zones 5b to 7b across the state--5b in the northernmost parts and 7b in the southernmost parts. Plants that are hardy in these zones generally can withstand the bitter cold of New Jersey. Perennial shade plants for this area thrive without the warmth of direct light from the sun.
Winter creeper, Euonymus fortunei, is a vinelike shrub from the bittersweet family. It gets 50 feet or more with aerial roots and 2 feet high. Leaves are oval and 1 to 2 inches long with small flowers and showy orange fruits. Winter creeper grows in any light with regular watering and in any soil. Propagate via tip cuttings, and grow in USDA hardiness zones 5 to 9.
Rusty black-haw, Viburnum rufidulum, is a drought-tolerant shrub that attracts birds. It is usually 10 to 15 feet high but can grow to 25 feet. Leaves are 2 to 4 inches long and oval with clusters of white flowers 2 to 5 inches wide. Rusty black-haw can tolerate partial shade or full sun and any soil. Propagate via seed or green-wood cuttings, and grow in USDA hardiness zones 5 to 9.
Spiderwort, Tradescantia Andersoniana group, is an easy-to-grow perennial that gets 1 to 2 feet tall and nearly the same in width. Flowers are 1 inch wide, and colors are dependent on cultivar. Flowers last nearly two months. Grow this one in partial shade in moist fertile soil. Propagate via clump division, and grow in USDA hardiness zones 5 to 9.
Indian pink, Spigelia marilandica, is a perennial that gets 1 to 2 feet tall with 2- to 6-inch-long leaves and 2-inch-long red trumpet-like flowers. Blooms are in spring and summer. Grow this one in sun or partial shade in moist soil. Propagate via seed or clump division, and grow in USDA hardiness zones of 6 to 9.
Surprise lily, Lycoris squamigera, is an easy-to-grow fragrant perennial that attracts butterflies. It has 2-feet-tall stalks with lilac pink fragrant flowers that are funnellike and 3 inches long. Leaves are grayish and 1 foot long. Grow this one in partial shade in any type soil. It can also tolerate full sun. Propagate via division, and grow in USDA hardiness zones 5 to 10.