The problem was that nobody knew how to run the farms. Rather than swallow their prides and get the former white owners engaged again, or even get help from elsewhere in the world, they just let the farms fail.
Sounds like the plot of The Turner Diaries.
Kinda hard to “engage” a former owner whose throat you’ve just cut.
This situation reminds of something I read about Russia after the commies took over in 1917. They fired most of the people who were running the utilities in the major cities and put loyal commies in charge. The problem: the loyal commies were screw-ups who had no idea how to run a hot bath much less complicated machinery. After awhile the head commies had to fire the loyal commies and put most of the non-commies who knew how run things back in place.
To farm, they gotta hoe, not HO.