Harvesting and Storing Pumpkins,
Winter Squash, and Gourds
Pumpkins: Halloween pumpkins are harvested September through October.
Sometimes harvesting may start in mid August to early September
which requires good handling and storage of the pumpkin fruit before
selling to the customers in late October. The first frost occurs
in early to mid October in northern parts of the state when the
pumpkin fruits are still curing outside in the fields. The growers
in pick-your-own pumpkin operations use this method to ensure that
pumpkins are well cured in the field before picked up by their customers.
Some growers practicing conventional pumpkin marketing systems where
the fruit is picked, washed, dried and sold to customers on weight
or per fruit basis also use this method. It is important to note
that pumpkin fruits can tolerate light frost that kill the vines
only but more fruit loss can occur if the frost caused injury on
the fruit surface as the damaged areas act as avenues for fungal
and bacterial fruit rot pathogens. Remove pumpkins from the fields
before the hard freeze (when the night temperatures are less than
27 degrees (F) or else you may risk losing 80-90 percent of the
The pumpkin fruit is harvested when it is uniformly orange and
the rind is hard. Green immature fruits may ripen during the curing
process but not after the vines are killed by frost. The vines need
to be dry when fruits are mature. 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 look
more attractive and less likely to be attacked by fruit rot pathogens
at the point of stem attachment. 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
remove the soil and kill the pathogens on the surface of the fruit.
Make sure the fruits are well dried before setting in a shed to
Pumpkin fruits are cured at 80-85F and 80-85 percent 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, the
fruits can be sold to the customers and the remaining fruits stored.
Store the fruits in a cool dry place. Put the fruits on a single
layer on wooden pallets with enough space in between the fruits
(the fruits should not touch each other) and do not place them on
a concrete floor. Improve the air circulation within the storage
area by letting in cool air at night and use a fan to circulate
air during daytime. Do not let in warm air from outside into the
storage during the daytime. The optimal storage condition is 50-55F
temperature and relative humidity of 50-70 percent. The relative
humidity is very important within the 50-70 percent range because
high humidity leads to settling of moisture on fruit surfaces, which
increases decay of the fruit and low relative humidity may cause
dehydration of the fruit. Under these conditions you can keep the
fruits for about 2-3 months. Store the fruits away from apples since
apples produce ethylene gas as they ripen which speeds up the ripening
process in pumpkins, hence decreased shelf life. Check the fruits
regularly and remove the ones that are rotten because if not removed,
they will spread the pathogens in the storage area.
Winter squash such as Butternut, Acorn, Hubbard, and other types
are mature when the skin (rind) is hard and cannot be punctured
by thumbnails. The mature fruit has a dull and dry skin compared
to shiny, smooth skin of immature fruits. Remove stem completely
from Hubbard types and if desired leave only 1-inch long stump on
the fruit. Stems longer than 1-inch tend to puncture adjacent fruits
when in transit or storage. Butternut, Hubbard and other squash
types do not need to be cured as the benefits are less compared to
pumpkins, while curing is very detrimental in Acorn types as it
leads to a decline in quality. Acorn types have the shortest storage
time of 5-8 weeks at 50F and relative humidity of 50-75 percent.
Butternut, Turban, and Buttercup types can be stored at the same
temperature and relative humidity as Acorn types but have a longer
storage time of 2-3 months. The Hubbard types can be stored much
longer than the rest (5-6 months) at 50-55F and relative humidity
of 70-75 percent. Winter squash should be marketed or used immediately
when taken out of storage to avoid development of fruit rot diseases.
Gourds are of different colors, shapes and sizes. They should
be harvested before frost when fruit is mature. As gourds mature,
stems turn brown and become dry. Don't use "thumbnail"
test on gourds as it can cause a dent on the shell of the unripe
gourd and lower its quality. Harvest the fruit by using a sharp
knife or shears to cut the stem from the vine and leaving a few
inches of the stem attached to the fruit. Do not handle the gourd
by its stem since the stem can easily detach from the fruit and
lower its decorative value. If the fruit is dirty, wash in soapy
water to remove soil and rinse in clean water with household bleach.
One part to 10 parts water kills soil-borne pathogens. Then dry
each fruit with a soft cloth. Spread the fruits so that they do
not touch each other in shelves lined with newspapers in a well-aerated
shed. Turn the gourds daily and change damp newspapers for 1 week.
The outer skin will harden this time and surface color develops.
The gourds need to be wiped with a damp cloth soaked in household
disinfectant and placed in a warm, dry dark area for 3-4 weeks for
further curing. The decorative gourd can stay in its natural state
for 3-4 months and as long as six months with a protective coat
of paint or wax on the surface.
October/November 2004: Diseases
and Insects of Shrubs and Small Trees | Does
Your Ash Tree Have the Emerald Ash Borer? | Harvesting and Storing
Pumpkins, Winter Squash, and Gourds