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Gardening Answers Knowledgebase

Plant Answer Line Question

Keywords: Pollination, Actinidia

I have two very healthy Kiwi vines, one male and one female. My female plant is flowering profusely right now, but there are no flowers on the male plant. I have had the plants for about 15 years or more and have never had fruit. They do not seem to bloom at the same time. I have just never bothered about it before, but this year I thought I would check out some options.

Any resources regarding hand pollination (both instructions and local suppliers) would be really helpful.


Oregon State University Extension's guide, Growing Kiwifruit by Bernadine Strik (2005), has information about pollination:
"For fruit to be produced, male and female vines must be present in a block and must flower at the same time. Male flowers produce viable pollen for only the first 2 to 3 days after opening. However, female flowers are receptive to pollen for 7 to 9 days after opening, even when the petals have started falling.
"Pollination is extremely important in kiwifruit production. Large fruit contain 1,000 to 1,400 seeds (research on Hayward). If pollination is poor, fruit will have indentations (narrow valleys) on one side or be non-uniform in shape. If you cut through these fruit, you will find no seeds in these areas.
"Kiwifruit flowers are pollinated mainly by insects, although wind may play a minor role. Honey bees are the main pollinator used in kiwifruit vineyards. Kiwifruit flowers do not produce nectar and are relatively unattractive to bees. About three to four hives per acre are needed to adequately pollinate kiwifruit. Place these in the vineyard no sooner than 10 percent bloom of the female vines.
"In some years, you may have no male vines in flower as a result of winter injury to male plants (they are less hardy than the females). In this case, no naturally produced pollen will be available. To get a crop, the females will have to be pollinated artificially. Call your county Extension agent for more information on sources of pollen and methods of artificial pollination."
(Note the section on Hardy Kiwi which are different than Fuzzy Kiwi.)

You might also find this article from The Olympian newspaper (May 16, 2009) of interest. It features kiwi growers Hildegard Hendrickson and 'KiwiBob' Glanzman, and discusses hand pollination, general care, pruning and training.

Date 2018-04-11
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Plant Answer Line Question

Keywords: Vaccinium, Pollination

What flowering plants should I place near my two blueberry plants in containers on my driveway that might attract the kinds of insects to maximize pollination of the blueberry plants?


Almost any plant that flowers at the same time your blueberry plants flower will help attract pollinating insects. This could be anything from apples to clematis to more blueberries. The Xerces Society (a Portland-based conservation organization) has published this useful fact sheet about choosing plants to help our native bees.

Date 2018-03-14
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Plant Answer Line Question

Keywords: Vitis, Pollination

What causes some grapes to get to normal size and others to stay small? This is on a Concord vine about 7-8 years old.


Some varieties of grape produce naturally straggly clusters of fruit. According to The Grape Grower: A Guide to Organic Viticulture by Lon Rombough (Chelsea Green, 2002), Concord has a tendency to ripen unevenly in hot climates (such as the mid-South), but he doesn't note straggly clusters as a characteristic of this variety. That makes me think the uneven size of your fruit is more to do with pollination. See the following, from Oregon State University Extension, which suggests that a cool, wet spell around the time of bloom can interfere with pollination and result in large numbers of unset berries. Rain, which also inhibits pollination, can also be a factor in poor fruit set.

There are other possible reasons for the uneven fruit set. If you are growing a variety of grape which is not ideally suited to your climate, or if the soil is overly rich or overly fertilized, you may not get abundant fruit.

Date 2017-05-12
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May 23 2018 14:32:42