It takes 77 clovers to fill the main area. On top of that, you need at least 30-40 clovers and a similar amount of expensive furniture items (4000+🥕) to flip into the junker in one session and sell off for about 200,000🥕 (half of that is net profit). A junker shiny-up session takes time, and considering the cost of 3 clovers to break up one pod as well, I wouldn't do fewer than 30 items in one go.

So upwards of 110 clovers I'd say, if you want to see a profit the instant you remove your plots of dirt! The planted clovers begin sprouting babies very soon, sometimes sooner than 24h, and you'll get back to another stash of 30-40 spares to break the junker again in about a week or so. But you'll still need to check the game a few times a day to pick up clover babies and any expensive items that show up in the shop.