פּירוש אויף בראשית 3:18

וקוץ ודרדר תצמיח לך THORNS ALSO AND THISTLES SHALL IT BRING FORTH TO THEE— תצמיח has for subject the earth; when you sow it with various kinds of grain, it shall bring forth thorns and thistles — artichokes and cardoon — which are fit for food only after special preparation (Genesis Rabbah 20:10).

וקוץ ודרדר, in lieu of the seed you plant beginning to sprout, the earth will produce thorns and thistles, which are not only useless, but which harm the plants your seed will produce, so that you will have to engage in eradicating them

קוץ ודרדר תצמיח לך, “it will grow thorns and thistles for you.” Until this moment the decree of Genesis 1,26 according to which the human species would rule in an unrestricted manner over all the creatures on earth had been in effect. There had been no need to guard the garden against invasion of wild beasts. From this moment on the negative phenomena on earth would be in effect, but would be directed only against the human species, לך, “against you.” The animal kingdom would not experience thorns and thistles as an impediment of their life on earth.

ואכלת את עשב השדה AND THOU SHALT EAT THE HERB OF THE FIELD — What curse is involved here? Was he not told as a blessing, (1:29) “Behold I have given unto you every herb yielding seed”? But what is stated here at the beginning of this passage? “Cursed be the ground etc.… in toil shalt thou eat of it.” And after all your toil “thorns and thistles shall it bring forth to thee”. This means when you sow it with cereals and vegetables it shall bring forth for you thorns and thistles and other weeds, and you will perforce have to eat them for lack of other food (Pirkei DeRabbi Eliezer 14).