Usually 99% of the fruit will fall off as the tree is not able to substain it. This is perfectly normal and is mother natures way of keeping the tree healthy. If the tree were to keep all of the friut it tries to produce it would put the tree under so much stress it would suffer greatly. The 1% that is left is all the tree is capible of holding.
Andi

Andy, I've read 2-4% fruit should remain on the tree, but doesn't dropping usually happen when fruit are larger than Gias?
Gia, make sure your citrus are getting enough sun, and don't overwater. Or underwater for that matter.
Are the fruit turning color before they drop? Toni

It happens from just started to look like a fruitlet and past marble size. Most will drop at the very small stage.

GD, is your tree getting appropriate sun and light? It's not being over or underwatered right? And be sure not to overdo it w/fertilizer, but do feed. Toni

Hi Toni,

I've seen you ask several times if the fruit are turning color prior to dropping when fruit drop comes up, but I don't think I've ever seen you elaborate more than that...What if they are turning and then dropping, what does this means as apposed to dropping while still green?

â£Gen

My Meyer Lemons seem to be doing wonderfully well, other than as described above, when the fruit is about a quarter of in inch the fruit turns yellow in 24 hours seemingly, and then drops. What is this indicative of, please? Thank you.

There is a fungus that will cause fruit drop in oranges but I don't know if this would affect your lemons or not. You can spray the blooms with a fungicide and see if it helps. Some commercial growers spray the trees(while in bloom) with 2-4-D to keep fruit from dropping. This may or may not be availiable where you live and you may or may not have to be a commercial grower to obtain it. Not sure on the regulations on this chemical.

I would not spray 2,4-D on your plant. First of all it is a weed killer not a fungicide. Second, do a little research on this chemical, it was actually one of the main ingredients in Agent Orange used in Vietnam to defoliate the forest.... Not good stuff. Here is a website with info - lewispublishing.com/orange.htm

Gen, sorry just noticed your reply..the reason I ask is because smaller fruit that change color and drop early happens for differnt reasons. Some fruit turns black..I deem this abnormal. I think the plant is being overwatered when this happens..I've also seen citrus where fruit dries up before it even had a chance to grow. I'm not sure if this is underwatering, but I'd say it is.
I've also seen fruit that looks mottled color w/webbing..this is a spider mite infestation. Fruit will drop suddenly also attacking the plant.
So, even though it's normal losing a percentage of fruit, I believe there are other reasons this happens. Sudden temperature can also cause problems..the fruit change color, sometimes appearing almost white..Then they drop. So, do you see why I ask? Toni

2-4-D on citrus:
http://www.ipm.ucdavis.edu/PMG/r107900311.html

http://www.inchem.org/documents/jmpr/jmpmono/v074pr13.htm

I was not suggesting the use but only said that some citrus growers use this technique to stop leaf and fruit drop.

There are several other components of Agent Orange that made it so bad. I am a victim of the stuff because my father was contaminated.

Believe it or not 2,4-D is still used in many applications in the foods we eat. 2,4-D has been deemed safe to use IF and I repeat IF, used correctly and according to regulations.

Wow that shocks me, how does an herbicide used to kill weeds stop leaf and fruit drop??? You learn something new everyday....

I hope the effects on you and your family were not to bad. I would be very careful with this stuff (and any other herbicide for that matter), remember they claimed DDT was safe for years and look how that turned out.

Thanks for the info Dragon!

GD, I'm terribly sorry about your dad..is he okay now? What happened to him, if you don't mind me asking?
Which foods contain this stuff? It makes me sick the way they use us as guinie pigs. Why are we eating chemicals in the first place?
This is another reason I only use safe products on my plants..By safe I mean home made.
You won't find a bottle of chemicals in my house or gh. I use everything natural..if I h ave a plant loaded w/pests, I use my organic brew, and if the trees/plants get really bad they go in the trash, but this is only after several applications of using my stuff.
I guess you can say I do use some chemicals like fertilizers. But after I'm threw w/all I have, I'm going to look into something safer like that V-11 or whatever it's called..I'd buy it now, but I've too much invested in fertilizers to toss out.
Again, I'm sorry about your father..I sometimes think that's the reason James Crockett died from cancer..he used so many chemicals on his plants..Toni

Thanks Toni,

I see why you ask now. I was just wondering cause last year when I first got my cal, the fruits were falling off when nice, green and firm. My lemon had 3 fruit maybe 1 1/2" long which were green when I got it, and then they one by one went sickly yellow and would drop very fast.

This year it's too early to see what the cal will do with it's fruit, but my meyer lemon had three flowers on it on the same branch, and three set, two went yellow and dropped when very small (â£Gen

My father died in 1984 of breast cancer. So far the only side effect I had/have is a mild learning disability/dyslexia which I have pretty much learned to overcome/cope with. I have 2 sisters who have had other problems ranging from cancer to joint problems.

2,4-D is the most widly used herbicide in the U.S.. While it was a component of Agent Orange it was not the main one that caused all the birth defects. Agent Orange was a mixture of 2,4-D and 2,4,5-T. The 2 mixed worked better than either alone. 2,4,5-T was found to be unsafe and was banned in 1983.

http://envirocancer.cornell.edu/FactSheet/Pesticide/fs14.2_4-D.cfm

The link above explains how 2,4-D is used today and what its used in/on.

Hi,i agree with everyone.Its normal for the tree to drop but
if they go yellow when very small,its usually too much water.
Another thing which i am aware of.When fruits are growing
growers often apply a fert high in potassium or potash to
encourage flowering and fruiting.From what i have found out,
this is wrong.The tree needs nitrogen to help set its fruit
properly and that why you should still feed your tree through
winter,keeping it strong ready for the spring flush.Your
tree needs nitrogen to help the fruits grow and set properly,
It helps if your tree has dark green leaves because the tree
also pulls nutrients from your leaves to help set the fruit.
Use a form of nitrogen that does not contain urea.
Feed with Balanced feed eg npk 20/20/20 and only water once
a week and deep.Personally,i thin out my flowers and vizulise a fruit there.Give them room to grow.I dont wait for the tree to drop the flowers.I pick out weak look ones
and leave room.I d this on my lemon and mandarin in the
ground.Good luck

I see the post about discolored dropped fruit possibly being result of overwatering. This is my fourth year with a potted Seville orange, so I am used to seeing many flowers and relatively few fruits. This year, though, most of the fruit (about 3/8 in. diameter) that looked as if it was going to stick instead turned black and dropped off at one time. The balls are kind of spongy. I suspect overwatering -- I give it a heavy watering about every two weeks -- perhaps in combination with our recent very hot weather. Any thoughts? I can live without the fruit but wouldn't like to make the same mistake twice.

Jen, discontinue watering every two weeks..there's no set schedule when watering plants. Only water when the soil is dry. Test the top 3"+..Toni