I have been growing three carob trees for just a few years. Two seedlings, a Tylliria and a Santa Fe and one cutting grown Sfax. This last fall the Santa Fe flowered for the first time and it turns out to be a male,
. I will graft some fruiting wood onto this tree. The Sfax had a pod on it when purchased, so I have at least one confirmed female. I purchased these trees from Exotica nursery in Vista, California.
I found a good write up on carobs: http://rfcarchives.org.au/Next/Fruits/Carob/Carob3-88.htm
which I believe was written in 1987 so keep that in mind when reading it and timelines are mentioned. I also found a nursery in Australia which has grafted carob trees available, Limestone Station in Broken Hill Australia. They advertised 7 varieties: Casuda, Clifford, Sfax, Santa Fe, Irlam, Tylliria, Waite. Maybe they know of how to innoculate a carob tree. Limestone Station nursery will not ship to me since my location is outside of Australia.
I am in Vista, California (San Diego county) where some very old and beautiful carob trees are growing. One of our schools, Vista Magnet Middle School ( formerly Lincoln Jr High and originally Vista High when built in 1938) has several ancient magnificent trees which I believe were planted when the school was first built in 1938. They may have been planted by Dr Coit who did some carob research in Vista at that time.
Oceanside, California and Coronado Island, California both have many old carob trees growing in their older neighborhoods. I am sure that the only reason the trees are still alive on Coronado Island is due to HOA homeowner rules and restrictions preventing new homeowners from chopping down mature trees. If it is a male tree the new owners don't like the smell during flowering season, and if it is a female they don't like all the pods when the fruit is ripe and starts dropping. Most of these people don't even know the pods are edible, let alone good for you!
I recently purchased carob (Santa Fe and Tylliria) pods from Mulberry Haven in Ojai, California. They primarily sell Mulberry fruit but also have carob pods. Carol Vesecky (owner of Mulberry Haven, 913 Oso Rd. Ojai, CA 93023 ) can be contacted at firstname.lastname@example.org
if you want to buy pods. She also runs a site http://biointensiveforrussia.org
for a vegetable growing method in Russia. She is usually pretty busy so be patient for a reply. Her carob pods were featured by John Kohler "Growing your greens" on YouTube.