garden variety

今日の表現もReader's Digest 1月号のKeep You MARRIAGE HAPPYにあったものです。
Of course, violence or verbal abuse is never acceptable, but the garden variety marital spat? It's actually good for you!
文脈からすると "garden variety marital spa" 結婚生活でのささいな喧嘩と推測できますが、 "garden variety" と言う表現は興味がわきます。　これは辞書に出ていそうです。
・Macmillan Dictionary: ordinary and not very interesting: We saw a show when we were in New York but it was nothing special - just your garden-variety musical.
・Wiktionary: (idiomatic) Ordinary, common, or unexceptional.: I can usually recover from a garden variety cold with rest and fluids.
・Cambridge Idioms Dictionary: very ordinary (always before noun) It's just a garden-variety shopping mall, large but not special in any way.

いつも思うのですが、英語の合成語のハイフンのあるなしは一貫性がありませんね。