Lavender Festival for 2017 has passed but the farms that participated may still be open for public visits. You will have to contact the farms individually but most have websites with their posted operation hours.
The festival is not going on right now, you'll need to look into the festival for July 20th through the 22nd 2018. You may be able to go visit the lavender farms though, you'll have to call each one individually to see when they are open. Just Google "Sequim Lavender Farms" to get all of the contact information for all of the lavender farms, there are a lot of lavender farms in Sequim.
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