Garlic on Pesach

There’s a common Ashkenazi custom to refrain from eating garlic on Pesach. I’ve heard several suggested reasons for them, but none of them sounded sensible to me. A while ago I discovered this account of the communal practice of Dembitz (Dębica), Poland, which IMO contains something of an explanation. It can be found in this translation of Dembitz’s yizkor book: The Baking of Matza Shmura by Yehuda Pechter

Here’s the text, followed by my interpretation of its significance:

Grandfather brought the wheat home in that cloth, and later placed it in a special place in the attic of the Hassidic Beis Midrash, next to the house of the Tzadik Rabbi Alter Pechter of blessed memory. There, grandfather spread out the wheat onto well laundered white sheets with his own hands in order to dry it properly. Only between Purim and Passover, once they had dried completely, did he sort out the “heads of garlic”, which were also considered to be complete actual chometz, and those who were extremely meticulous in the performance of the commandments would be very careful that not one “finger” should be found among the wheat that is being prepared for the matza shmura.

I think this passage is relevant to the custom of avoiding actual garlic. The wheat kernels described here are probably ones which had become damp and had therefore sprouted or become subject to fungal growth, and consequently unsuitable for matza. But I have observed that stringencies on Pesach often develop around things that are even verbally associated with chametz. In this case, wheat that was “a head of garlic” was considered to be chametz: by a verbal similarity actual heads of garlic were forbidden as well. We shouldn’t imagine that this was an error or due to some sort of imagined contagion: as the account says, the job of sorting wheat was one entrusted to relatively few people in the Jewish community, and probably never to more than one or two in a village. How could the traditions relating to it be passed on? By encoding it verbally. The identification of “heads of garlic” in wheat was assissted and protected by the common understanding that garlic itself was not to be consumed on Pesach.