This is one of the results - morning glory which I chose for its blue flowers. The seedlings turned yellow and died except for this one which struggled for a while, but after it started growing its true leaves, it spiralled quickly and evenly up my washing line pole without any guidance. The delicate flowers open in the morning and fade in the evening.
The leaves reminded me of the bindweed which attempted to strangle many of my plants last year. Unfortunately, I have just found out that morning glory is in the same family as bindweed (convolvulaceae). As I have decided not to use artificial weed-killers or fertilisers (until I'm forced to at least), I controlled the bindweed this year by raking the undergrowth in the spring and keeping it clear. I think the best solution for weeds is to plant lots of plants.