Two varieties of plums pictured above and below. One is a Pembina and the other is unknown.
Photos by Anne M.
We can grow some delicious plums here in Alberta. One problem we sometimes encounter here in the prairies is the tendency toward chlorosis. Our soil is very alkaline, making it difficult for some trees to access the iron necessary. Gardeners may apply chelated iron to supplement their trees. Maples can have the same problem. I've even seen it in roses and peonies!
Plums that are hardy here include: Brookred, Pembina, Opata, Brookgold, Ptitsen #5
Wild plums, though very difficult to find, like prunus nigrus (Canada Plum) which grows in the states and in some areas of Alberta and Saskatechewan near rivers, and prunus americana (American Plum), are the most successful pollinators of hybrid plums according to the University of Saskatchewan where they've been growing wild plums from seed. Wild plums tend to flower a bit later and it has been suggested for them to be effective pollinators for early flowering hybrids, the grower should train lower branches to grow near the ground where they will be "fooled" into blooming earlier. It is essential that pollinators bloom the same time as the chosen hybrid plum.
Cultivars of prunus salicina, commonly known as the Asian or Japanese plum, bloom early and are good pollinators for eachother. Sour cherries will not improve pollination of hybrid plums though both are in the prunus family. Most sour cherries, ie. Nanking, Evans, are self-pollinating. Sandcherries are good pollinators for cherry-plums like Opata.
For more information on research on plums for the prairies see this document: