Hello,

Well, I don't believe their is a "Best Time for Harvest per say". I believe that much more than type effects this. Here are some things to consider:

1) Variety & Species of Fruit, time to maturity - Every variety of citrus has a slightly different time to maturity. Lets assume your Oroblanco grapefruit tree takes 11 months to maturity. So if you blosom and have a flower fertilized in January, then your grapefruit will be mature for plucking in the begining of December.

2) Citrus typical time to maturity - There is none, however, in the US a have seen a lot of timeframes for Nov-Dec or Jan-Mar. Also with different varieties and species that you own each one matures at different rates. homecitrusgrowers.co.uk has harvested between X-Mas and New Years day, however, that doesn't necessarily mean that that is the best time to harvest.

3) Syncing your citrus - In other words, make the fertilization time of your flowers occur manually by you. Clip off flowers too early or late from your fertilization time. Once again lets make some assumptions.

Grapefruit - 11 months
Lemon - 8 months
Lime - 10 months
Orange - 9 months

BTW, none of these times are to be quoted, they are just examples.
Use the Grapefruit as the babis for when you would like your harvest as it has the longest maturity period. Lets also assume that your trees flower over a broad period of time like 5-12 months of time. Also not true numbers but an example. If your grapefruit flowers in Jan, then the lime should be in Feb, the Orange in Mar, and the Lemon in April. Of course this would probably reduce your total fruit gross at the end of the year but that would be a drawback I guess.

3) Health of your trees - If your trees are unhealthy in terms of bugs, disease, fertilization, water or light depreivation, etc, then these will effect whether the fruit grows too slow, matures to fast, or at all.

I am sure there are other factors to effect time to harvest but these are what I could think of off the top of my head.

So the answer to your question is there is no official time to harvest. Observation and knowing how long it takes for your fruit to mature will determine the best harvest time for you. I believe times for your fruit to mature per fruit may be available from your plant supplier(s), and on the web. Also if nothing pans out ask for times to maturity in this forus. Who knows, some fellow posters may know the value of these 4 varieties.

Anyway, that's my 2 cents ;)

VTY
-Mark

'Oro Blanco' -- I can't be certain on this one, since it's a California variety, seldom seen in Florida. But since it is grown in CA specifically because it's less acidic than most of "our" varieties, I'd expect it to be early -- likely by early December. But I'm not sure. Another thing to consider is that the true grapefruit will hang on the tree for quite a long time, after reaching maturity, and stay pretty good in quality. 'Oro Blanco' may do that too, but I really don't know; it is part pummelo, so not a pure grapefruit. Under Florida conditions, pummelos tend to dry out rather badly if left too long on the tree. So I don't know if that trait was passed along. In any case, California data will not work here; our climates are so different that maturity dates virtually never match up, even within several months.

'Key' lime is ready when the fruit turn yellow. They'll usually be somewhere between the size of a U.S. quarter and a golf ball.

'Bearss' lemon (and all other lemons) are "ready" any time they are big enough to suit you. The bigger they get, the juicier they'll be, but commercial lemons from Florida are always picked grossly immature and then colored up in coloring rooms. Since the goal with a lemon is very high citric acid content and low sugar content, physiologically green is better. If you leave them on the tree, they'll become huge, sometimes exceeding the size of a large grapefruit. If you don't mind that look, they will be loaded with high quality juice at that time. I'd still pick and use them before they turn yellow.

Red navel -- decent by late November; really good by mid-December, most years. On a young tree, they'll dry out shortly after they reach maturity, so if you let it hang on the tree into January, you're likely to be disappointed.

Grapefruit and oranges tend to be seasonal here; lemons and limes tend to have multiple crops per year.