[SallyintNorth]

Sometimes starting again is what you need to do. You can get some lovely permanent wildflower mixes to drill after ploughing. Make sure you spray it off before ploughing or you’ll just plough dock seeds down which will germinate again. We reseeded a very docky, wet field last year and it’s like a different field now (still wet, but that’s a drainage issue).


I’ll run away now before the anti plough, anti spray folk start chasing, it’ll give me a head start 

Irrespective of our own opinions, the OP states that it's organic land.  So spraying will not be an option.  It would depend on the circumstances as to whether ploughing might be okay.

[Steph Hen]

Yellow rattle in the mix whatever you end up doing. Scotia seeds, if you’re in Scotland.
There are other hemiparasitic herbs.

[Backinwellies]

It has no other plants growing on it bar some thistles, dock and other grasses. It has been completely over run by the grass in question. Unfortunately leaving it in the past is what has allowed it to spread across the site. The only way to stop it getting worse would be to have it regularly cut low something the landowner doesn't want. Livestock would not be an option.

If not to be grazed or mowed then will never be a wildflower meadow .... it is the grazing/mowing which allowes the wildflowers to multiply.   

If this is purple moor grass (which is likely if it is a wet field) then it is a rare habitat and supports many species
 
https://www.daera-ni.gov.uk/sites/default/files/publications/daera/Habitat%20Guide%20-%20Purple%20moor-grass%20and%20rush%20pasture.PDF