Answer: Bittersweet may take a year or so to become established, but then usually grows rampantly each year. If you feel the need to encourage a plant, you might try an application of compost and/or a complete granular fertilizer such as 10-10-10 in early spring and again in early summer according to the label instructions.
There are many reputable nurseries operating as both local businesses or as national mail order companies. Some may specialize in fruiting plants, or in perennials or bulbs, or offer a general line. You might visit nurseries in your area and talk to neighbors who garden as well as investigate some of the mail order houses and see which ones offer the types of plants you are looking for. Again, friends and neighbors will probably have some favorites.
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