By Contributing Columnist Richard Olsen-Harbich Contrary to popular belief, rain is not always a four-letter word to the winegrower. Grapevines — like all other plants — need water to survive and grow. Early season rains help the vines start their growing season and lead them into a hopefully, long, hot summer. Improved vineyard management and disease control techniques have recently shown that late season rains have less effect on wine quality than once thought. And, there’s another fact about rain that goes without saying — we can’t do a thing about when and where it occurs. A lot has written…