Posted: 01/05/2012 at 11:09
Weeds will come first, as they are the natural plants to the area and the country (unless it is an un-natural import such as balsam and japanese knotweed) so have the resources to grow well here. A weed is ony a plant you feel is in the wrong place, your sweet peas will grow and catch up, outgrowing low growing weeds, but I'm afraid you will still need to keep on top of them if your imported flowers -i.e. sweet peas, are to grow well.
We all love our imported flowers, me included, but do tend to forget where they originated and developed, then wonder why they sometimes don't do well when we offer them opposite places in which we expect them to grow. Export pansies to Africa, and they won't grow there either, without a vast amount of care (I know, I tried!).