Where was that drawing board?

Oh, it's so annoying.
I don't have much problem writing description, or realistic dialogue (at least, of types of people I know). My grammar and vocab toolkits are fine: I'm lucky to have had a good education first time round, so I started off with good basic writing skills. Ideas, as is often said, are ten a penny. My problem is definitely with plotting. I start by visualising an idea or a situation, but then what happens? Not enough, generally.
And that's certainly the problem with the current WIP. It's nicely written (I think), but short on conflict, of all types. The hero and heroine like each other straight away; she's broken off her previous engagement in chapter one; I have a great many peaceful scenes of farming, and no great dramatic set-pieces lined up in the wings. This book will be boring if I don't deal with this.
Oh well. Let's find out more about the characters, and try again.