Yellow Tree


November 2, 2023

During spring when the flowers begin to open, the bees and orchard managers are working hard to ensure a successful pollination in the orchards.


Kiwifruit flowers are very difficult to pollinate successfully. This is due to their lack of nectar, the number of pollen grains required, the cost of pollen, the weather during this period of the year, and the synchronisation of flowers opening.


Kiwifruit flowers don’t have nectar, which means they are not attractive to bees who would much prefer the clover in the grass of the neighbours flowers. To combat this, beekeepers and managers must feed the bees “sugar water” as a replacement for nectar.


Each female kiwifruit flower requires 3,000 grains of pollen. This means a bee must visit a single flower multiple times before it can turn into a flower. Even if orchardists apply pollen mechanically or by hand, the cost of pollen is a huge restriction to the pollination process. Just 1kg of pollen in the 2023 season costs $12,000 - $15,000. Because of this, many growers rely on natural pollination, or apply at small rates which may not be sufficient.


The weather over the pollination period is also crucial as bees are not active during the rain. During the pollination season in mid spring, weather events often occur in the middle of 100% full bloom. The flowers open up at different times across an orchard, and managers must balance the inputs to equal the rate of open flowers (e.g. 10% flowers open = 10% of total hives required or 10% of artificial pollen applied).


There are two different kinds of artificial pollen (human applied pollen). These are dry pollen and wet pollen. Dry pollen is as it sounds, which is dry pollen grains blown up into the canopy. Wet pollen is when pollen is mixed with water and dye to become visible and sprayed on the flowers by hand or machine. Wet pollen is often used closer to wet weather events. Kiwi Pollen states that dry pollen is best when male flowering is less than optimum, orchards have insufficient male vines, and when requiring a pollen top up. Wet pollination is best for insufficient male vines, bee pollination is not sufficient, when bees prefer other crops, and when wind rain and cold weather is affecting bees.


Orchards with overhead hail cover also cause issues for bees as they can get lost if they do not have external objects to navigate home to the hive. This causes up to 40% of bees getting lost and dying which is costly for the beekeeper.


Pollination is one of the few things which can hugely affect an orchards performance based on numbers of fruit correctly pollinated, dry matter levels, and the overall quality of fruit.