Articles

By Rabbi Dovid Cohen, Administrative Rabbinic Coordinator

Q. My grocer sells lettuce grown locally though “vertical farming”.  What is that, and does it have any kashrus implications?

A. Scientists have discovered that it is possible to grow plants without sunlight and without soil (!).  The plants grow indoors, in nutrient-filled water, with climate-controlled environments, and special colored lighting, all of which allows “farms” to grow all types of produce in warehouses or anyplace else.  The term “vertical farming” comes from the fact that these growing beds can be stacked on top of one another.

One halachic issue which this raises relates to the proper bracha recited before eating vegetables that grow in this manner.  Some Poskim follow the lead of Chayei Adam who ruled (in a similar situation) that that the bracha is shehakol, because the wording of the bracha “Baruch…who creates the fruit of the earth” (borei pri ha’adamah) is inappropriate for items that grow unattached to the firmament or that grow in non-earth-like media (e.g., water, coconut coir).  However, Rav Shlomo Zalman Auerbach and others argue that the bracha of borei pri ha’adamah was instituted for all vegetables, regardless of exactly how they grew.

A related question is whether romaine lettuce grown at a vertical farm can be used for marror at the Pesach seder.  While some have suggested that Chayei Adam et al would not allow it, Chazon Ish conclusively proves that it may be used.  The Gemara says that wheat which grew unattached to the ground (i.e., in an atzis she’aino nakuv flowerpot) may be used to produce matzah for the seder, and another Gemara indicates that the qualifications for matzah and marror are similar.  This indicates that romaine lettuce grown in an indoor/vertical farm may be used as marror.

The fact that produce has a different status when it is grown indoors and not in soil, opens interesting possibilities as relates to shemittah.  During the shemittah year, farmers may not plant, weed, and do other work on the ground, but – if certain conditions are met – those restrictions do not apply to vertical farms.  Accordingly, there are some growers in Eretz Yisroel who take advantage of this and structure their greenhouses or other growing areas to comply with these requirements, allowing them to operate during shemittah.

The area where vertical farming offers the most promise for kosher consumers is in its potential to allow for insect-free vegetables.  By its very nature, an indoor farm offers some protection from insects, and in many cases the “farmers” themselves will add measures, such as air locks and water filters, to minimize those insects that might ruin their crops.  Nonetheless, experience has shown that even with these and other lines of defense, bugs may still find ways to infest these plants.  As a result, Mashgichim must continually sample produce and evaluate what is effective and which areas require improvement.

This article first appeared in the Let’s Talk Kashrus column, Yated Ne’eman, September 27, 2024.