Answer: Grapes should not be pushed to hard with fertilizer.
In late winter, just prior to spring bud break you can give your new grapevines about a cup of a complete fertilizer, spread evenly around the plant. As plants grow, increase the fertilizer amount by a little each year. Judge how much you need by last year's growth. Lots of vigorous growth means cut back on the fertilizer a little. Weak growth may be an indication the plant needs more.
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