Expert: Nick McCann Date: 7/4/2008 Subject: Lemon Tree
Question QUESTION: We have a fruit tree that has one trunk of large leaves, thorns, and large green fruit that look like lemons that in three months have become very large. The other trunk is small leaves and what looks like small limes. We cut open one of the large green fruit and it does not look citrus inside. There is a 1/2 inch white ring of pulp and a centre of slightly yellow stringy seady stuff about one inch in diameter. No segments. What is this fruit? I bit into it and my tounge and lips were burning tastes sharp but not lemony smells like lemon though.
ANSWER: Hi Linda, when you purchase a Citrus tree from a nursery or whomever (home depot etc.) it is a grafted tree, this means that the crown (surface) is grafted (adhered onto) a rootstock (from soil level down under)..this rootstock is almost always a variety called "Sour Orange" , it is very resilient and resistant to disease, so its the best of both worlds, you have a surface fruit that is very desirable, ie. sweet orange, lemon, lime or grapefruit, while the undesirable "sour orange" is kept at bay and only serves as a hardy root stock; now we will get in to the problem, when the root stock (as it will do over time) manages to send out a sucker that isn't cut off before it develops, and this sucker takes off, then you end up with a crown of "Sour orange" and it shares the crown with the original variety that was grafted on to it. I think you see what has happened to your tree now, the root stock has overpowered your lime, which was the original variety and has become the predominant fruit on your tree. Sour Orange is just that, a large orange shaped fruit that looks great, but tastes extremely bitter, like a lemon. It will bear an awful lot of fruit, that unfortunately is not very useful, even when ripe. I hope this helps you understand what has happened, most people cut the Sour Orange trunk and then this allows the preferred variety re-establish itself. Nick
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QUESTION: I am a Canadian living in California. Thank you it took me 2 hours to find you, the person who could answer my question. Now, how do I cut the trunk about four inches, the lime is about 2 inches. This sour orange is 20 ft tall. I don't want to hurt the lime and promote its production. Thank you. God bless America!
Answer You need to cut the sour orange back to soil level and completely eradicate it at that point, you will see an area at the bottom where the original lime tree was grafted, the sour orange will have developed beside this and then excelled; trace the sour orange down to the ground and with a sharp saw cut it there, leaving the lime tree to develop on its own without competition. It is a large tree and you may need to get a landscaper to do this process for you, just make sure he does exactly what i said, so as not to impede the Lime tree...:)..Nick
