Which Fruit Is Orla
Do not eat tree fruit for the first three years of the tree (orla); any tree fruits from the fourth year (neta revai) must be redeemed with a pruta before eating, even outside of Eretz Yisrael.
NOTE: It is not possible to redeem neta revai in the old city of Jerusalem!
Which Uses Are Prohibited
You may not use orla fruit for any type of use or benefit (asur b'hana'a); the prohibition is not just for eating.
Which Part of the Plant Is Prohibited
Only orla fruit is forbidden, but the tree may be used.
Who Is Prohibited from Growing Orla
Orla applies to fruit grown by both Jews and non-Jews.
HOW TO CALCULATE ORLA
Orla Planting Deadline
Trees planted at least 45 days before Rosh Hashana (that is, by Tu B'Av) are considered to be one year old on that Rosh Hashana.
How To Calculate When Orla Is Over
You may eat tree fruit if the tree's buds appeared after Tu B'Shvat of the fourth year. This may be a span of only 2.5 years if the tree was planted on or before Tu B'Av (at least 45 days before Rosh Hashana):
1st Year - Tu B'Av to Rosh Hashana #1
2nd Year - Rosh Hashana #1 to Rosh Hashana #2
3rd Year - Rosh Hashana #2 to Rosh Hashana #3
4th Year - Rosh Hashana #3 to Tu B'Shvat
EXAMPLE: A fruit tree planted on Tu B'Av, Aug. 15, 2011, will be one year old 6 weeks later, on Rosh Hashana, Sept. 29, 2011. By Rosh Hashana, Sept. 5, 2013, the tree will have completed three years and it enters its fourth year. Buds that appear on or after Tu B'Shvat, Jan. 15, 2014, and turn into fruit will be neta revai and may be redeemed and eaten.
Doubt about Tree Age in Eretz Yisrael
Do not eat fruit from a tree growing in Eretz Yisrael if you are not certain about the age of a tree that might be three years old or less.
Doubt about Tree Age outside of Eretz Yisrael
You may eat fruit from a tree growing outside of Eretz Yisrael if you are not certain about the age of a tree that might be three years old or less.
If a tree (whether younger or older than 4 years) is transplanted but did not have enough soil on its roots to live for several years, restart counting orla from zero.
Grapes outside of Eretz Yisrael
Outside of Eretz Yisrael, only grapes (not other types of “tree” fruit) need to be redeemed in the fourth year of their growth in order to eat them.
NOTE: We are lenient in using commercially grown grapes due to doubt as to the grapevines' ages.
Papayas in Eretz Yisrael
Papayas grown in Eretz Yisrael may not be usable, since papaya trees don't normally live for four years.
NOTE: There is a difference of opinion as to the blessing over eating papaya— borei pri ha'eitz or borei pri ha'adama.
Copyright 2015 Richard B. Aiken. Halacha L’Maaseh appears courtesy of www.practicalhalacha.com Visit their website for more information.