You are an agriculture and email marketing expert. Write a detailed, 2400-word guide on email for farmers. The guide must cover: 1) Building an email list (farm stand, CSA), 2) Welcome sequences for CSA members, 3) Weekly harvest and availability emails, 4) Seasonal and holiday campaigns, 5) Farm updates and stories, 6) Recipes and cooking tips, 7) Customer appreciation and loyalty, 8) Referral and friend campaigns, 9) Re-engagement for inactive members, 10) Metrics for farms (CSA sales).