Hi everyone, first time posting here, but I'm glad I was able to find such a complete site for information. I have a grapefruit tree in my living room that I've planted from a seed about 16 years ago. It's about 7 feet tall now (and about as large), and always been healthy, although it never flowered. I live in Montreal, so the temperature is too cold to put it outside about 3/4th of the year. So anyway, as I said my tree has always been healthy (aside from loosing a bunch of leaves in winter, but I guess that's normal?), but a few weeks ago I noticed that a bunch of leaves were turning slowly from green to yellow from the edges, and upon closer inspection I saw some very fine web between some leaves. At first I just thought some normal spider made it's way there so I sort of ignored it, but when leaves started falling and more were turning yellow, I pulled out a magnifying glass. All the yellow leaves have some very fine web under them, and on some webs I could clearly see some very tiny things crawling all over the place. http://img154.imageshack.us/img154/2165/img0404.jpg (Infested branch, all the leaves on it fell when I tried to clean it of the mites) I've done some research, I'm no expert but I believe they're Two Spotted Spider Mites or Glasshouse spider mites (Or are they the same? If anyone can confirm it, I'd appreciate a lot), I removed all the webbing i could find with a wet cloth, but they seam eggs under the leaves of half my tree. I tried to find how to get rid of them, and the 2 options I found was either to spray pesticide on every infected leaves, or deposit a little army of predatory insects over my tree. And both seam to be undoable since the tree needs to stay in my living room for at least a few weeks (the temperature still drops at about 40-45 at night, or should I put it outside for that very reason? would the cold kill the mites before it hurt the tree?). So for my questions, can those thing kill my tree? What would be the best (and less invasive) way to get rid of those things? Also, a couple questions on an unrelated note, should I pry all the dead branches? There's also 2 small branches growing near the very bottom close to the earth, they're healthy branches, but I was wondering if I could remove them to keep the lower part of the tree clean, and it's give more nutrient for the top part of the tree(?). Thats for reading, and for any help/information you can give me :) http://img140.imageshack.us/img140/4052/img0408w.jpg (My whole tree, a little healthier than it it right now)
First, it is not normal to lose a lot of leaves every winter. What is happening to your grapefruit is called Winter Leaf Drop (WLD). There is a lot of information on this form giving advice on how to avoid this from happening. Place the words "WLD" or Winter Leaf Drop" in the search function on this forum and you will learn how to keep this from happening. Second, your tree has Citrus Red Spider Mites, and spider mites can certainly kill your tree is not eradicated, and should be controled quickly. As old as your tree is, I am very surprised that your tree has not been infested with mites before, as this problem is quite common on citrus. Three thing you can do. 1). Spray the entire tree down 3 times at two or three day intervals using a solution of 1 tablespoon soap dissolved in a gallon of water. 2). Purchase a horticultural oil (Volk Oil, or UltraFine Oil) at any Home Depot, large garden center, or Lowe's Garden center. UltraFine Oil is extremely easy to locate in the States, but Canada is often another story when trying to find chemicals. Horticultural Oils are absolutely non toxic, and work VERY WELL against aphids, spider mites, mealy bug, and fairly good on white fly. Make a 1 percent solution of oil and water and spray your tree. 3). Take the tree outside and hose the tree down using a forceful spray with your garden house (3 applications once every 3rd day.) When you spray using any of the above methods, be sure to throughly get both the upper and lower leaf surfaces, and all the wood. Then keep a sharp eye for any re-infestation, resulting from from eggs. It looks like you have done a good job cultivating your grapefruit tree. Unfortunately, of all the varieties of citrus grownfrom seed in containers, grapefruit is the worst variety to choose if fruit is ever desired. The chance of a containerized grapefruit ever fruiting is almost zero. Key Limes from seed will fruit in 2-3 years. Mandarins from seed will fruit in 5 years, Oranges and lemons - 10 years. Good luck. - Millet (1,350-)
