seed planting

i haven't planted seeds before. (guilty confession) but i'm planning on planting morning glories this week. in my mind, i'm going to go out there, dig a bit of a trench, sprinkle those babies in it and cover it up. i live in eugene oregon, so rain is plentiful (but they wouldn't be in a position to be washed away). i'm still scouting for something upon which to let the little darlings climb, but is there anything else i need to know? oh yes. the place i'm planting them is quite full of hyacinths right now (from someone previous). do i have to dig those bulbs up or can i just sprinkle the seeds around them, or whatnot?