I am sorry for this delayed reply to your gardening question. We are transitioning to a new Q&A system and your question was unfortunately lost in the transition. I have discovered it now and hope this reply is not too late to be of help.
Thompson has some difficulties in your climate. Generally speaking it should start to fruit about year 3. The key is to keep the soil moist but not too soggy and use mulches or sprays to keep weeds well away from the vines. Fertilize with a cup of turf fertilizer spread evenly throughout a 5 foot circular area around each plant in March and May for the first few years.
Your County Extension Office can assist by providing info on pruning and general care of grapes for your area of the state.
Thanks for the question. Please stop in again soon!
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