Grafting: Where is there a list of all the kosher combinations?
Question
Is it permissible to plant a tree from a lemon tree scion grafted onto a hushhash (sour orange) rootstock? Is there a comprehensive list of all the permissible grafting combinations? Are there any nurseries that follow halacha?
Answer
Rabbi Yehuda HaLevy Amichay
Since hushhash is considered safek mino (possibly the same species) vis-à-vis lemon trees, it is possible to commission a non-Jew to plant it on your behalf.
A comprehensive, up-to-date guide of kosher scion-stock combinations can be found here (in our Halachic Guides section on grafting).
There main nursery that we know of that observes the halachot of grafting—Mermelstein Nursery in Ganei Tal (next to Chafetz Chaim): 072-3954724, or on their website.
See here for the full list of nurseries.