Jewish Law

Kilayim Between Trees and Vegetables



 I work in a Nursery School and in that Nursery School we have a garden. On last Tu BeShevat we planted an apple tree there. At the end of the year planted tomatoes. I just realized is there a problem of Kilayim (cross-breeding). If so, what should we do?


They are not forbidden. It is permitted to plant a vegetable next to a fruit tree even if the roots will tangle since it happens underground, and you may continue growing them.

There are three categories of Kilayim (by plants):
  1. Mixing seeds
  2. Mixing other plants with a vineyard
  3. Mixing trees
Two different seeds are forbidden to be planted together or and they must be uprooted. They are not forbidden to eat. It is not forbidden to mix seeds in Chutz La’aretz.
If one plants grapes and other vegetables, they become forbidden to eat and to derive benefit from. The Chachamim forbade mixing even in Chutz La’aretz.
Planting different trees together or a tree and a plant is not forbidden fi they are just next to each other (unlike grapes and other plants). It is only forbidden to graft two trees together.
The Rambam rules (Hilchot Kilayim 1:6,7):
One who grafts one tree on another, for example a branch of an apple tree on an Etrog tree, or vice versa, receives Lashes from the Torah…It is permitted to plant plants and trees together and is also permitted to mix tree seeds, since there is no Kilayim by trees except grafting.
However, if the roots of plants mix under the ground why is that not Kilayim?
The Chazon Ish (Kilayim 13:10,11) explained that everyone agrees if one had intent to cross breed trees by planting them together it is forbidden. There is an argument only where they are planted next each other, and they mix by themselves under the ground. The Rambam (and Gr” a) rule they are permitted. The Ra”sh, Ro”sh, and Tosfot rule it is forbidden.
That is only a disagreement by a replanted grape branch and another plant, since the roots entangle the branch. If it is just roots mixing the Ro”sh is even more lenient.
The Ran and the Shach (YD 295:1) that even roots entangling is forbidden, but if it was under three Tefachim in the ground is permitted. So, in this case since the roots will mix under three tefachim below ground it is permitted.