Rootstock and interstem grafts can influence hardiness, when fruit is produced and how well a tree is anchored in the soil. Apple rootstocks vary in susceptibility to collar rot and fireblight. Rootstocks are referred to by a rating system seen in the following graduated illustration of tree size. Generally speaking, the more dwarfing the rootstock, the sooner after planting the tree will bear fruit. 12 to 18 feet tall, and full-size trees up to 30 feet.
Genetic dwarfs are a more recent horticulture introduction.
Although genetic dwarf cherry, peach and nectarine are sized for patio growing, fruit quality probably will not equal that of standard varieties. Each gardener must examine the intended planting site for microclimate. Frost-sensitive peaches and nectarines often lose their crop to late spring frosts. The following chart presents information about fruit trees and low temperature hardiness. These conditions can cause bark splitting and death of twigs, branches and buds.