Fertility
If the plant bears crops, it indicates the plant's fertility or fecundity.
SF = Self-fertilizing. A plant bears fruit on its own because it is self-pollinating.
DSF = Partially self-fertilizing. A plant bears fruit on its own, but will produce more - and usually larger - fruit if it cross-pollinates with another plant. This plant must then be of a different variety.
SS = Self-sterile. A plant by itself will not bear fruit. It must cross-pollinate with another variety.
H+H = These are male and female plants, and both are needed to bear fruit (dioecious). Usually, one male plant will be enough to pollinate several nearby female plants.
TR = Triploid. Does not have viable pollen and therefore cannot pollinate other varieties. This is the case for some apple varieties, so 3 varieties are needed if all are to be pollinated.