Plants on a windowsill during shemitah

Answer

Greetings,

The Jerusalem Talmud (Orlah 1:2) is inconclusive whether the shemitah laws apply indoors. Furthermore, plants growing in an unperforated planter are obligated in the land-dependent mitzvot only miderabanan. For this reason, during shemitah Chazal permit growing plants in unperforated planters indoors, since safek derabanan lekulah (we are lenient with uncertainties rabbinic in nature).

In light of the above, if a planter on the windowsill is unperforated and is under a shaded area, it is considered indoors, and it will be possible to grow crops in it during shemitah. However, it is important to ensure that the plant's branches and leaves do not protrude from the planter and the entire plant is in an unperforated planter. However, if the branches spread out above the ground, the plant receives its nourishment from the ground—even though it is considerably higher than the ground. In this case, it would be considered a perforated planter.

However, if the plant is in an unperforated planter in an unshaded area, it is not considered indoors. In this case, shemitah laws apply.

The same is true if the planter is in a perforated planter (e.g. placed on a wide bars, not on an area with a bottom). Even if placed under a shade, the laws of shemitah nevertheless apply.

For a full article named "Guidelines for Growing Indoors on Detached Platforms", see here.