If you were to mow the area repeatedly,to a low setting, you will reduce/eliminate many of the weed population as they reduce in ability to photosynthesise, flower and seed. You also provide a ‘free’compostable ingredient. Create a lawn in other words.Shortness will allow the cardboard to rest at soil level and soften more rapidly when/if it rains again.
If you can source suitable plants (brassica?) then a late summer planting could bring in a crop for this year end.
Apart from cycle shops, retailers of white goods (fridges etc) and fireplace/stove shops will give you lots of card-just ask.My local supermarket has a cardboard recycle bin and will let one remove the fly-tipped boxes that arrive even when the bin is full. Card will also compost, especially with the ‘lawn’ mowings. Beware the box staples-they bite.
