There is also a setting in Preferences>Note input and Editing:
Preferences are under the Edit menu, or press Ctrl/Cmd+,.
Checking that setting will give you the crescendo you see below when selecting the C and F#. Leaving it unchecked will extend the hairpin until the end of beat 1. I believe it’s unchecked by default (it was one of the first things I changed when starting with Dorico).
The above is the result I get without the need to edit any Engraving options for hairpins (apart from barline interaction which I have set to stop before barline, but I don’t remember if that’s the default).