Official position: sex is for procreation. In marriage. Period.
Reality
5-8 children over 20 years. Meaning: sex is regular. But no Amish person would say 'we have sex for pleasure.' Even if true (and it likely is — 300 years of culture doesn't cancel biology).
What's Known
From ex-Amish accounts: sex at night, in darkness, under covers. Minimal conversation (before and after). Initiative — male (usually). Refusal — wife's right (usually doesn't refuse, but can). Oral/anal — taboo (but who checks?). Masturbation — sin (but a sin nobody talks about = a sin hard to control).
Education
Zero. Absolute zero. Not in school, not at home, not from elders. Farm is the only textbook (animal mating). Result: first experience — awkward, brief, embarrassing. By year ten — normal. By twenty — habit. By thirty — warm routine.