Debbie Ann said, "So I let part of the row go to seed this winter/spring.
I feel the problem is that the seeds were not planted at the recommended depth.
Since you let the plants go to seed, the seeds just fell to the ground and sprouted.
I am not sure if anything can be done with the radishes this year.
Since you mainly like the greens, just go ahead and let them grow.
Next year maybe you can use organza bags to keep the seeds from landing on the ground so you can plant them.
There still may be some benefit to the ground though I don't know.