Pollination groups explained
When planting fruit trees, whether they’re in your garden, a school or a community orchard, you will need to consider pollination groups to ensure your trees will bear fruit.
Self-fertile varieties
Some fruit tree varieties are self-fertile, meaning that they will pollinate themselves without the need of a pollination partner. Self-fertile trees can also be pollination partners for other varieties in a compatible pollination group. Some varieties are partially self-fertile, meaning that they can pollinate themselves to an extent, but would benefit from a pollination partner to produce a more abundant crop.
Self-sterile varieties
Fruit trees that are self-sterile need a pollination partner to produce fruit. The pollination partner must:
Be planted close enough to ensure pollinators can move between the two trees, e.g. in the same garden or in a neighbour’s garden.
Be of the same fruit variety (e.g. apple, cherry etc.)
Be in a compatible pollination group. Pollination groups are denoted by a letter (A, B, C etc.) and each pollination group is compatible with itself, as well as with the letter on either side of it in the alphabet. For example, an apple tree in pollination group C can pollinate an apple tree in group B, C or D but not A, E, F, G, H.
Not be a triploid variety (more information below)
Triploid varieties
Some apple trees are “triploid” varieties. This means they have three chromosomes rather than the normal two. Not only are these varieties self-sterile, but they also cannot pollinate other apple trees. Triploid varieties tend to be very vigorous and often have good disease resistance.