In article , David Hill
writes
I'd would use the "Stale seed bed" technique.
Work the ground as normal and get it ready to plant or sow seeds into,
then let a flush of weed come through, hit them with Weedol; a contact
weed killer then plant or sow a couple of days later with as little
soil disturbance as possible.

It might be a good idea just to identify the weeds first. For instance
are they really perennials or maybe very fertile annuals that are self
seeding quickly like bittercress.
--
Janet Tweedy