Kilayim 2:9-10

Kilayim 2:9

Let’s say that a person wants to divide his field into a number of patches, each planted with a different crop. He can divide a field of a beis seah into 24 patches, each a beis rova in size, and plant each patch with any species he may desire. (A beis seah is about 5,625 square feet; a beis rova is about 225 square feet.) If there are one or two patches, he can plant mustard. If there are three patches, he may not plant mustard because that’s an awful lot of mustard, so it will cause the field to look like a mustard field rather than just individual patches. This is the opinion of Rabbi Meir; the Sages allow a person to plant up to nine patches with a single species. Ten are too many because they require an empty patch between every two sown patches. (In a 5x5 grid, nine is the maximum number of patches that can be sown non-contiguously.) Rabbi Eliezer ben Yaakov says that even if a field is as big as a beis kor (about 170,000 square feet), only one patch may be sown with a different crop.

Kilayim 2:10

The measurement of a beis rova includes everything in it, even if it’s not plantable land. This includes such things as the space occupied by a vine, a grave, or a rock. One must separate two different types of grain the distance of a beis rova; two types of vegetables must be separated at least six cubits (about nine feet). Grain and vegetables must be separated a beis rova; Rabbi Eliezer says six cubits.