Successful apple cultivation depends on pollination, the movement of pollen from one flower to another to allow fertilization. The goal of an apple tree’s bloom is to convert its delicate flowers into viable fruit, which is only triggered after successful fertilization. Without this transfer of genetic material, the blossoms will simply drop, and no fruit will develop.
Understanding Apple Pollination Requirements
Apple trees are categorized as either self-fertile or self-unfruitful. A self-fertile tree can use its own pollen to set fruit, allowing a single tree to produce a crop when planted alone. Most commercial apple cultivars, however, are self-unfruitful, meaning they possess a genetic mechanism that rejects their own pollen. These varieties require cross-pollination, which is the transfer of pollen from a genetically different apple cultivar.
Cross-pollination requires pollen to travel from one tree to a different variety’s flower. Insects, primarily honeybees and native bees, are the main vectors for this transfer. The bee collects pollen from one tree and deposits it on the receptive stigma of a flower on a different, compatible tree, initiating the fertilization process that stimulates fruit development.
Pollination Status of Gala Apples
The Gala apple is generally considered a self-unfruitful variety. This means it requires a separate, compatible partner tree to produce a satisfactory harvest. Although some sources classify Gala as partially self-fertile, the resulting yield from self-pollination is typically too low to be considered successful. For reliable fruit production, cross-pollination is a necessary requirement.
Gala is a diploid variety, meaning it has two sets of chromosomes and possesses a self-incompatibility gene system. This system prevents fertilization when pollen from the same tree or an identical variety is used. When a Gala flower receives its own pollen, the growth of the pollen tube is blocked. A different cultivar’s pollen is required to bypass this genetic rejection mechanism and stimulate the flower to develop into an apple.
Selecting Effective Pollinizer Varieties
To ensure a successful crop of Gala apples, a gardener must plant a different apple cultivar nearby that meets two specific criteria. First, the partner must be a distinct variety, such as Fuji or Honeycrisp, and not just another Gala tree. Second, the pollinizer variety must have an overlapping bloom time with the Gala apple. Gala is typically a mid-season bloomer, so the partner tree’s flowers must be open and producing viable pollen during the same window.
Effective pollinizer varieties that share a compatible mid-season bloom with Gala include:
- Fuji
- Honeycrisp
- Granny Smith
- Golden Delicious
Planting one of these varieties within 50 feet of the Gala tree maximizes the chance of bees successfully transferring pollen. Crabapples also serve as excellent universal pollinizers because they produce abundant, long-lasting flowers compatible with most standard apple varieties.