Kate,
oh blimey ..two years of weeds and THEN you stopped...the first couple of years is really the worst time for weeds. All the weed seeds in the soil get their chance to germinate after years of being dormant. The best way round it , if you have the patience ?I don't!! , is to clear the plot, dig it and remove all perenial weed roots, and then let the weeds germinate. After a few weeks remove all of those , either with a hoe or just pull them out . Then let them germinate again , remove again , do this 4 or 5 times and nearly all weeds will have gone. That way you have an empty plot for the first year . I can never do it that way , I just clear what is there let one lot germinate , clear and then plant my veggies, and do loads of weeding ...lol. It is though as I said the first couple of years that are the worst . The number of weeds that pop up after that is very few. Another thing to remember with weeds, and is very true , one years seeding is seven years weeding !!! so never let a weed go to seed. Most have loads of seeds and will cover a plot in no time.
Regarding wild flowers, the thing to remember with them is , they need no fertilizer , in most cases the poorer the soil the better sort of... Most wild flowers will find it hard if not impossible to cope with fast growing modern grass, they will get swamped by it and just disappear. one way to get them established is to make little clear patches of ground and sow in those , like little mini flower beds. They should grow ok in those and go to seed ,and then slowly spread their way about.
As with all things there is no easy fast way round it really .... It is just a matter of trial and error , to find out what will grow in the situation they are in . What you have to work out is, do you want all the flowers to be wild type ? and just from that area ? That way you can find out what are native to your area and plan your seed sowing from there, or go the non wild route and sow just what you want there , taking into consideration the conditions that they are being sown into. Hope that helps a bit ....not sure if it does though ..?
cheers
Russ