Will a red splendor crabapple tree cross pollinate a honeycrisp apple tree?
Thank you for the question. Honeycrisp apple trees bloom mid season. According to Ohio State Extension, Red Splendor crabapple trees bloom early in the season. Generally crabapple trees bloom longer than apple trees so there might be some overlap but not for sure. Bloom time is also directly affected by environmental factors like wind, rain, freezes, and frosts. These factors can decrease bloom times so it's impossible to predict from year to year just when crabs and regular apple's will bloom and how long the blooms will last.
University of Illinois Extension states that Red Splendor tends to flower heavily on alternate years so pollinating opportunities may be less some years.
If there are other varieties of apple or crabapple trees close by, your Honeycrisp will probably be fine because there will be a variety of bloom times.
Read more here to learn more:
This publication provides information on many different crabapple varieties http://ohioline.osu.edu/sc154/sc154_12.html
Thank you for contacting Extension.