Answer: Properly trained and trellised, grapevines usually produce a full crop of grapes by the fourth year. Concord grapes are not especially suited to your gardening region; they require long, hot summers, such as experienced in Central California, as opposed to your year-round mildly warm climate. They may produce grapes, but you shouldn't expect a bumper crop each year. Grapes are an important addition to your landscape, though. They can be trained on an arbor or trellis where they'll grow lush and green each summer, providing shade, interest in the garden, and an occasional bonus of edible fruit.
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