Plant to Pick: BlackIce Plum

By Debbie Lonnee, originally appeared in Northern Gardener Magazine

May 2020

Black Ice PlumGrowing your own fruits and vegetables has been a hot trend for gardeners lately, and in the cold north, we have our challenges with cold hardy cultivar selection, especially when it comes to fruit trees.  Luckily, the fruit tree breeding program at the University of Minnesota has yielded a lot of great varieties, from apples to apricots, but there is also some fruit breeding being done just across the state border in Wisconsin that is yielding great plants for Minnesota gardens.

BlackIce™ plum was developed by Dr Brian Smith at the University of Wisconsin-River Falls, and is now being produced commercially for homeowner use.  If you would like to grow your own ‘California’ type of eating plum, you should give this cultivar a try.

It is a cross between a cherry plum and a conventional Japanese dessert plum.  The fruit is quite large and is early ripening.  The fruit is similar in size to any large ‘black’ plum you would buy in the grocery store, the ripening time is easily 2-4 weeks early than most Japanese plums.  In the Twin Cities, it ripens in early August.

The fruit has that dark skin (a blue almost black color), but the flesh is a beautiful reddish color, is firm, juicy and tastes just great for fresh eating (I can’t wait to try to make some plum jam with it, too!)  It is considered a semi-clingstone type. 

It has been proven to be hardy and to produce fruit in USDA hardiness zone 3b, so most Minnesotans should be able to successfully grow this tree.

Propagated via budding, it is grown on Prunus americana understock, but has a nice compact growth habit, making it easy to manage from a pruning and harvesting perspective.  It will reach a mature height in the landscape of 8-12’.  You will need to have a pollinator tree in the vicinity (within 100 yards), and you could use straight Prunus americana, or the cultivars ‘LaCrescent’, ‘Underwood’ or ‘Waneta’ for successful cross-pollination.  It will bloom in late April to early May, with small white flowers.

Although fruiting plum trees can be affected by some insect and disease problems, I find they do not need the regimen of fruit tree spraying that apple trees need. 

Photo Credit: Jung Seed