In this Issue:
Harvesting and Storing Pumpkins
| Vol 5 No. 9 | October 10, 2003 |
Harvesting and Storage of Halloween Pumpkins
Reprinted with permission from: Illinois Fruit and Vegetable News: Vol. 9, No. 15, September 29, 2003, Maurice Ogutu, University of Illinois
|
It is important to
note that pumpkin fruits can tolerate light frost that kills the vines only,
but fruit loss can occur if the frost affects the fruit itself. Slight frost
injury on the fruit surface can provide avenues for fungal and bacterial fruit
rot pathogens. Remove pumpkins from fields before a hard freeze occurs (when
the night temperatures are less than 27°F), or you risk losing 80-90% of
the fruits.Some guidelines:
- In general, harvest pumpkins when they are uniformly orange and the rind is hard.
- Green, immature fruits may ripen during the curing process but not after a killing frost.
- Vines need to be dry by this time.
- Handle the fruit with care to avoid cuts and bruises.
- Harvest the fruit by cutting it off the vine with a sharp knife or a pair of looping shears, leaving 3-6 inches of the stem attached to the fruit. This makes the fruit looks more attractive; it is also less likely to rot.
- Do not carry the pumpkin fruit using the fruit stems because the fruit is very heavy and may lead to detachment of the fruit stem.
- Wash the fruit with soapy water containing one part of chlorine bleach to ten parts of water to kill the pathogens on the surface of the fruit.
- Ensure the fruits are well dried and set in a shed to cure.
Pumpkin fruits are cured at 80-85°F and 80% relative humidity for 10 days. This is done to prolong the post harvest life of the pumpkin fruit because during this process the fruit skin hardens, wounds heal and immature fruit ripens. After curing, fruits can be sold to customers or stored.
Store pumpkins in a cool dry place. Put the fruits on a single layer on wooden pallets with space in between the fruits (the fruits should not touch each other); do not place them on a concrete floor. Improve air circulation within the storage area by letting in cool air at night and use fans to circulate air during the day. Do not let in warm air from outside during the daytime. The optimal storage condition is 50-55°F, with a relative humidity of 50-70%. Under these conditions you can keep the fruits for about 2-3 months. Store the fruits away from apples because apples produce ethylene gas as they ripen, and ethylene speeds the ripening process in pumpkins and decreases their shelf life. Keeping relative humidity within the 50 to 70 percent range is important, because very high humidity leads to settling of moisture on fruit surfaces, which increases decay of the fruit. Low relative humidity may cause dehydration of the fruit. Check stored pumpkins regularly and remove the ones that show signs of rot, because if not removed, pathogens will spread within the storage area.
Co-Editors: Bill Hutchison, Department of Entomology,
University of Minnesota, hutch002@tc.umn.edu
Jeanne Ciborowski, IPM Program, Minnesota Department of Agriculture,
jeanne.ciborowski@state.mn.us
Production Editor: Suzanne Wold Burkness, Research Fellow, Department of
Entomology, University of Minnesota, woldx018@tc.umn.edu
Last Revised October 9, 2003.
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