Patricia M. Arledge, Sharpe, Kenneth W. | 11/6/2013 1:32:38 AM
News Article for October 21, 2013:
My grandmother used to say that a watched pot never boils. The same saying can apply to citrus getting ripe. I have had a number of inquiries into how to tell when satsumas are ready to be harvested.
The simple answer is, you have to taste them. The early varieties of satsumas, such as Armstrong, Louisiana Early and Early St. Ann will mature in September through early October and you can find those varieties in the market place now. The next variety to get ripe is Brown Select and growers will start harvesting it around Halloween. The most popular grown Satsuma variety is Owari and we usually start to harvest it the second week in November or about two weeks after Brown Select.
In talking with the County Agent in Plaquemines Parish, he says the crop is right on time and most growers have a bumper crop on the trees. When you have a bumper crop the fruit will tend to be a little smaller due to the total pounds of fruit on a tree.
There are test that growers can use to determine the sweetness of citrus and to determine if they meet certain standards. One test is the percentage of juice content. This test is an important measure of internal quality as under or over-ripe fruit tend to be less juicy. Another is the Brix test which is a measure of total soluble solids, which are primarily sugars. And the last component is the acid test, which is a measure of predominately citric acid which will account for the tart taste.
The final measurement for sweetness is a ratio of the soluble solids (sugars) to citric acid and the minimum requirement is a ratio of 10 to 1. Now for all of us non chemist the best answer is to taste. Not everyone likes the same taste, some of use like them a little sweeter and some like them a little tarter. Citrus will not continue to ripen after you pull them from the tree so you need to make sure they are the desired sweetness when you pick. As a rule the earlier you pick, the less sweet and the later in the season you pick, the sweeter.
While we all like to see that orange color on the outside peeling, and it can be an indicator, it is not the best tool to determine sweetness. The color change seems to be more of a time of year issue and the earlier varieties especially can still be green but ready to harvest.
If you were not one of the lucky ones that has a bumper crop of satsumas this year it could be fertilization. On mature trees of 4 years of age and older, we recommend fertilization in late winter and again about June 1st. Missing the June fertilization can lead to alternate bearing or having a good crop only every other year.
Another problem that is prevalent in citrus this time of year is leaf footed bugs, which some of us also call stink bugs. They are particularly troublesome as the fruit begins to get ripe and starts to turn from dark green to light green. The bugs have a piercing mouth part which they insert into the fruit and extract the juice, leaving a clear hard spot in the interior of the fruit. Homeowners do not have lots of options but you can be successful with an application of ultra-fine oil plus Malathion. The insects will have to be present when you spray in order to kill them with this mixture. Wait 7 days after spraying with Malathion before harvest.