Thursday, January 01, 2015

More on Bagging Fruits for Protection. 1.1.15

This is my momentary obsession for gardening.  It will pass.  Something to read and learn during winter.  Meanwhile, some references.

oisat.org describes how to make fruit bags from newspapers.  I can see that working in dry climates, or summer fruit in dry summer areas, such as here.  "works well with melon, bitter gourd, mango, guava, star fruit, and banana" "...prevents insect pests, especially fruit flies, from finding and damaging the fruits. The bag provides physical protection from mechanical injuries (scars and scratches) and prevents female flies' laying activities, latex burns, and fungal spots on the fruits. Although laborious, it is cheaper, safer, easier to do, and gives you a more reliable estimate of your projected harvest."  They use  double layers of the newspapers and sew or stable them to make the bag.

Detailed discussion for various fruits, on Hawaiifruit.net.    They used manufactured bags of various types from Japan.   It's interesting, they note " For hundreds of years throughout most of Asia, farmers have been covering fruit with paper either to protect their appearance or to increase the time the fruit would be on the tree thus making it sweeter." and "This practice first came to Hawaii with the early Japanese immigrants and in the 1920’s Ohau farmers employed school children to wrap figs."  They describe their experiment showing of the first 100 bagged figs, 94 were harvested undamaged.  Six were damaged, thought due to rats.  Of 100 unbagged fruits, 86 were damaged beyond recognition by birds.  Because of the bird damage, insect damage was not possible to assess.  

The Hawaii article discussed multiple varieties of fruit.  The only ones I can grow from their list, are figs.

From rfcarchives.org.au, "In Japan where the average orchard is only two to three acres, bagging is an important cultural operation for fruits such as loquat, persimmon and nashi fruit (Asian pear). ...  bagging is undertaken to reduce the number of pesticide applications and to improve fruit appearance.. provides a major defence against fruit piercing moths ...makes po ssible the production of fruit of a very attractive blemish-free fruit with considerable eye appeal."  Some of the bags in Japan are impregnate with pesticide, something I won't do.  The article goes on to state bag are used for mangos in the Philippines.  Among the types of bags, newsprint was one type that worked well to dramatically reduce insect damage.  Plastic bags did not work well in their work with mangos.  On the same website, one writer used nylon bags made from old curtains, with successful protection of the fruit (1983).   

This article on pears, did not describe insect damage, but rather lack of negative changes in pears due to bagging.  "
Preharvest bagging of pear fruit (Pyrus communis L. ‘Doyenne du Comice') with micro‐perforated polyethylene bags c. 30 days after full bloom did not affect fruit size and weight, density, maturity, and flesh content of N, P, K, Ca, and Mg. Bagged fruit had a greener and lighter skin colour than non‐bagged fruit, whereas the development of blush on the sunny side was not different between treatments"

Apparently, bagging can also be beneficial for persimmons.  

What interests me here is that, in so many years of gardening, I haven't read about bagging fruits.  I'm sure the method will not benefit all fruits, in all climates, but it looks like it's worth testing for apples and a number of other fruits.  It's surprising the method has been around so long, and so widespread, and yet is not part of the general gardening knowledge here.

Edit:  Adding more articles.  In Sicily, in the province of Enna, peaches are bagged in parchment paper bags.    The resultant peaches are called "Pesca Settembrina".   A farmer came up with the bagging method in the 1960s to save peaches from the Mediterranian Fruit Fly.    Also "The pulp firmer and more acidic, due to the slow maturation, make it particularly suitable for the preparation of jams; are excellent in combination with the white meat which give it a special taste."... " The remedy comes a few years later: the parchment paper bag in which the fruits are wrapped 120-150 days before fully ripe peaches protects from pests, from the weather and avoid the excessive use of fertilizers from industrial sources."








1 comment:

  1. Bagging did not work for me. Moisture stayed in the bags, apparently sweat from the fruits. Most of the fruits developed rot on the surface. Despite following the directions carefully, this method resulted in fewer usable fruits, instead of more.

    ReplyDelete