Hello Citrusenthusiast, If you are willing to start small, take a handful or more 4 to 5 inch cuttings, and follow the rules for rooting them with rooting powder or liquid. I took three cuttings from my Key lime this past fall, dipped the cut ends in the rooting hormone powder, popped them into separate little two inch pots, kept them under plastic bags in indirect light in my house, and got one to take. I lost the other two because I totally forgot to check to see if they needed watering. Regarding the fear of spreading disease, I think that unless every last suburban landscape crew, professional and amateur, in southern California is practicing "safe" pruning techniques you really are unlikely to be guilty of a major crime. I lived for a decade in Florida, including a couple years in Sarasota in the early 90s, where citrus canker disease was a major concern, and I used to watch the supposedly professional landscape crews working through the citrus trees that grew on the apartment complex's property, and I never ever saw them sterilize their pruning tools--which were reportedly a potential way the disease could spread, even though Sarasota had several major citrus groves within a few miles of the location. Up here in Connecticut, I try to remember to always wipe my pruning shears with rubbing alcohol after trimming each tree I have, even though, obviously, I don't exactly have to worry about infecting nearby citrus plantations. I hope you have good results, and that you get a few other people interested in your Grandma's tree. Don

I think limes taste best when they are fully ripe and the rind is yellow. It is also possible that it was grafted to lemon rootstock. If you have allowed the rootstock to branch you could be getting lemons from that. Most such rootstock is a rough looking lemon that isn't very desirable in looks or flavor.

According to the "book" and what I've read thornless don't yield as much. Whether it's enough to matter to the average homeowner I don't know. Also IME Persian Limes (especially) & Key Limes are very underrated for their cold hardiness. TRUE Lemons are over rated. I have about 20 citrus trees in the ground and my Tahitian lime is one of the hardiest & most cold hardy here in zone 9B. The only citrus trees I have ever lost to low temps were a full sized Harvey Lemon and a mid sized Varney Navel tree back in our record 2010 freeze here when he got down to about 20. Nothing else even got burned. I have seen a lot of nurseries saying Tahitian limes are cold sensitive and I have not found that to be the case. Lemons I have.

Parker T - > just FYI - in my particular yards, I had conflicting scenarios (after dips to 18-19F) but have a different preference. I've "soured" on any cultivar with 'quat in its name; they are not as cold hardy as I had hoped. In Napa, the Eustis Limequat (on Volk) was killed to just about the graft - regrew and is now 10 ft. tall - took over a year. The Bearss lime just lost its leaves and refoliated, produced a huge crop right away. In Danville, the Bearrs lime was completely destroyed, the Volk rootstock lived. While the Eustis in my neighbor's yard was defoliated and came back. From what I've seen since, the Eustis fruit gets destroyed quickly when the temps go below freezing. The Bearss lime fruit can and has survived to 29/30F. So my vote is for the Bearss or Persian lime -because I want fruit! - far better for my climate's fall/winter dips below freezing. - George