By Robert Cox, Colorado State University Cooperative Extension, horticulture agent
For a crab apple tree to pollinate an apple tree to produce fruit, conditions must first be just right.
Crab apples produce fruit less than 2 inches in diameter, and apple fruits are 2 inches in diameter or greater. Most crab-apple varieties tend to bloom a little earlier than most apple varieties. If the crab-apple and apple bloom periods overlap, there's a good chance that the crab apple will pollinate the apple. Ideally, they should be within 50 yards of each other.
Photo: Judy Sedbrook
© CSU/Denver County Extension Master Gardener 2010
888 E. Iliff Avenue, Denver, CO 80210
Date last revised: 01/05/2010