The chief virtue in rape as a nurse crop is that the shade is removed early through pasturing.
When thus grown, the preparation of soil for the nurse crop will usually suffice for the clovers also.
Whether it is advisable to sow a nurse crop will depend upon conditions.
If sown later, the seed will more certainly make a stand without a nurse crop, since it will get more moisture.
If not thus clipped, they would frequently injure the crop more by shade and crowding than would a nurse crop.
When sown with a nurse crop, the seed is in some instances mixed with the grain before it is sown.
Since it is liable to be more injured, relatively, by a nurse crop than the clovers, it is more frequently sown without one.
The other clovers are usually able to make a sufficient stand, though grown along with a nurse crop.
Sweet clover may be sown with almost any kind of a nurse crop desired, which does not destroy it with an over-abundant shade.
Some have advocated sowing clovers without a nurse crop under any conditions.