Pollen compatibility
Most apples will pollinate other varieties but there are some important exceptions to this rule.
In general, varieties that are closely related (that is, with similar parentage) are not the most effective pollinisers for each other. For example, Cripps Pink (which produces the Pink Lady™ apple) is only a fair to average polliniser of its parents, Lady Williams and Golden Delicious, and its sibling Cripps Red (which produces the Sundowner™ apple).
Varieties that are sports (derived from mutations) of the same parent variety are considered to have incompatible pollen and cannot be used to pollinate one another. For example, Royal Gala will not pollinate Gala or Galaxy; Naga Fu No 2 (Red Fuji) will not pollinate Fuji.
Triploid varieties such as Mutsu and Jonagold have sterile pollen and cannot be used as pollinisers. Where a triploid is grown as the main variety it is not uncommon to have two polliniser varieties. This ensures that an economic crop is obtained.
Environmental conditions
Apples, like many fruit trees, are reliant on insects for successful pollination. Favourable environmental conditions over the flowering period are essential to achieve good pollination. Where weather conditions are poor through prolonged rainfall and low temperatures, insect movement is limited and pollen viability also decreases. The use of well designed natural or artificial windbreaks can improve the orchard environment for beneficial pollinator insects.
Pollen-transferring insects
For consistent pollination across the orchard to be achieved there must be sufficient numbers of pollen-transferring insects, the most significant being honey bees. If pollination has been poor historically, or feral honey bee numbers seem low, it may be wise to bring in hives from a commercial beekeeper.
If you plan to bring in hives it is advisable to arrange this with the beekeeper well in advance, allowing suitable hives to be prepared. For more information about bees and availability of hives contact the Pollination Association of Western Australia, telephone +61 (0)8 9572 6116.
During the flowering period it is essential to avoid applying chemicals that will harm bees and other pollinating insects. Always choose bee–friendly chemicals where possible and ask your local chemical supplier about suitable bee–friendly chemicals at the time of purchase.