I have been groing a small grape fruit tree from a seed out of a grape fruit purchased at a grocery store. I recently transplanted it into a much larger pot. Initally it really took off, but now it's stopped growing and it's lead leaf just fell off. Would the transplanting and a new more shady location be to blame? What should I do?
What was the condition of the leaf? Was it wilted? Crispy? What is condition of the rest of the tree? If I had to make a guess I would say your tree is suffering from root rot. You transplanted to a "much larger" pot. Citrus trees require a quick draining medium to grow in. An oversized pot in relation to the root mass will result in a medium that will stay wet for a long time which in turn is conducive to root rot. It's likely that you have this tree indoors at this time of year. So other possibilities include low humidity (particularly in a centrally heated home) and cold or warm drafts. Give the tree plenty of light. Then again there may not be anything wrong. What is the size of the leaf that fell off? Citrus grows in flushes. When growth stops at the end of a flush the tip abscises and falls off. This is normal. You'll find a lot of useful information if you browse or search through the citrus forum. Apparently many people like to grow grapefruit from seed.
I agree with Junglekeeper 100 percent. The biggest mistake many people make is usually not in the type of pot but by using too large a pot. People think that they are doing the tree a favor by giving it a lot of room. But if the plant doesn't grow fast enough to use most of the space, trouble can and usually occurs. An oversized pot can become waterlogged easily, and then the tree can suffer from lack of air (yes, roots need to breath too). The soil quickly becomes sour, causing many problems to the plant's health. When you are up-potting a root bound tree, it is best not to jump to a size any bigger than 3 - 4 inches larger than the original container, or 1 - 2 inches if your are up-potting a small seedling tree. If the tree has not already filled the pot it is presently growing in then there is not need to up-pot. This is a very common mistake, and it is the tree that almost always pay a terrible price. - Millet
