Reference for Shabbat 190:1
אלא להכשיר זרעים בלבד א"ל לכל מילי רבי שמעון כתלוש משוי ליה ושאני לענין טומאה דהתורה ריבתה טהרה אצל זרעים שנאמר (ויקרא יא, לז) על כל זרע זרוע אשר יזרע
is in respect of making [its] plants fit [to become unclean]?<span class="x" onmousemove="('comment',' Edibles, e.g., grain, vegetables, etc-, can be defiled only if moisture has fallen upon them after they were detached from the soil. Now, a perforated pot is regarded as attached to the soil, and therefore its plants cannot become susceptible to uncleanness; whereas an unperforated pot is detached, and so if moisture falls upon its plant, when grown it is henceforth fit to become unclean — This shows that R. Simeon too recognizes this difference. ');"><sup>1</sup></span> — In all respects, answered he, R. Simeon treats it as detached, but in the matter of uncleanness it is different, because the Torah extended [the scope of] cleanness in the case of plants [seeds], for it is said, [And if aught of their carcase fall] upon any sowing seed which is to be sown, [it is clean].<span class="x" onmousemove="('comment',' Lev. XI, 37, i.e., if it is in any way attached to the soil it is clean, and this includes a perforated pot. ');"><sup>2</sup></span> A certain old man asked R. Zera: If the root is over against the hole, what is R. Simeon's ruling then?<span class="x" onmousemove="('comment',' If one tears out that root on the Sabbath (Rashi). Here the root draws sustenance directly from the ground. ');"><sup>3</sup></span>