This is how Opium poppy (Papaver somniferum) grows in the wild. Watch out!
 Mugwort is a herb known to induce labour, assist in birth and afterbirth and ease labour pains. When Mary mentions saffron, we can assume that she’s referring to the common pain-killer which was popular in those days, made of 2 ounces of opium; 1 ounce of saffron; a drachm of cinnamon and cloves - all dissolved in a pint of Canary wine.
It is likely that Mary also read “The English Physician” (1652) by Nicholas Culpeper (1616–1654), who spent most of his life collecting and cataloguing hundreds of medicinal herbs. As we become acquainted with Mary, we can again assume that she liked Culpeper for his attitude.
Besides believing that no authority was beyond questioning, he was also critical of the unnatural methods of his contemporaries, and he worded that in such poetic, un-scientific ways:
"This not being pleasing, and less profitable to me, I consulted with my two brothers, DR. REASON and DR. EXPERIENCE, and took a voyage to visit my mother NATURE, by whose advice, together with the help of Dr. DILIGENCE, I at last obtained my desire; and, being warned by MR. HONESTY, a stranger in our days, to publish it to the world, I have done it!”