Crossbownation forum is detailed on how to do it, depending on make and model. The cocking rope sure helps but the cam timing and a2a is also needed to be super accurate. There are ppl like the field archer who is known for it.
Cam timing and A2A length needs to be in tune as well. Most importantly how one cocks the crossbow makes a difference between shots.
If one pulls harder on right hand vs left then the center or nock point changes in xbow.
I have tried turnips and radish but the deer didnt bother with them until late in winter when they dug them up from the snow. Hunting season was long over.
Would planting beans and then fencing it with electric work or have you tried it?