Top 5 Cold Hardy Cherries for the Prairies

Top 5 Cold Hardy Cherries for the Prairies

The first Zone 3 cold hardy cherry was a dwarf tree, eventually named ‘Evans’ after being rediscovered by Leuan Evans in an old farm orchard near Edmonton Alberta in 1976. I remember this tree coming on the garden centre retail market during the mid-1980’s and it was a very big deal.

The U. of S. Fruit program is responsible for introducing cold hardy sour cherry shrubs bred just for the Canadian prairies. The breeding work was started by Dr. Les Kerr in the 1940’s! The first introduction (Carmine Jewel) available to garden center customers was not until 1999 after years of field tests and trials. The Romance Series of five cherry cultivars was then introduced in 2004 by Dr. Bob Bors. The word sour to describe some of these cherries is somewhat a misnomer, as when fully ripe, most are very sweet.

Sour Cherry Plant Info and Care

Hardiness: Zone 2 and 3

Location: Full sun.

Soil: Loam or sandy loam soil - (pH 6-7). They will tolerate amended clay soil if the area has good drainage.

Planting: Plant 2.5 cm to 3 cm deeper than the depth of the container. In amended clay soil, plant about 5 cm. deeper.

Water: Newly planted shrubs, keep moist for the first month. During hot weather check every two days for water needs. They may not need water every second day but it is always wise to check. Once established, a regular watering schedule is all they need.

Fertilizer: Fertilization is only required once per year, about a month before spring bloom. Use a low nitrogen fertilizer such as 5-10-10.

Pruning: Prune back older branches in early spring which will encourage new growth. The Romance series cherries can be kept at a 2 m. height and width. Remove any crossed, dead, dying or diseased wood. Old fruiting branches may stop producing leaves - these branches can be removed as well.

Depending on the cultivar, dwarf sour cherries will ripen from the last week in July to the second week in August.

All are disease resistant but watch for Cherry Leaf Spot, Brown Rot and Cherry Fruit Fly. Do not overhead water as this may encourage powdery mildew and other foiliage diseases.

Sour cherry shrubs are grown on their own roots. They are not grafted onto hardier rootstock. You cannot get much hardier than Zone 2! The roots produce some suckers which should be left with the shrub. The fruit produced on these suckers will be the same as on the parent bush.

Clusters of white flowers appear later in spring (mid to late May); avoiding late frosts.

Sour cherries are self-pollinating. While you can grow just one sour cherry shrub or tree it is advisable to plant another Cupid or Romance Series Cherry to encourage better pollen movement by bees and other winged pollinators.

Shrubs trained as trees are less hardy and more susceptible to sunscald. If you plant a tree, be aware not to disturb the soil around the trunk after planting as this encourages suckering. Allow a 1 m. -1.5 m. diameter bare area around the trunk. After planting you can lightly mulch around the tree and be diligent about pulling any weeds around the trunk as well. Fully wrap the young tree in winter to fend off deer, rabbits and porcupines.

Sour cherry shrubs will begin to fruit about three years after planting. Trees will take longer – not fruiting until they are 5-6 years old. The cherries should be picked when fully ripe and that means waiting until they reach a rich, deep color. Pick the fruit in early morning or early evening.

As the cherries ripen birds may become a problem. Use fine bird netting or floating row cover and make sure it covers the entire shrub right down to the ground and anchor to the ground with stakes. You can also use old CD’s, tin foil pie plates, aluminum foil strips and placing more desirable bird food away from the area. I would also seek the advice of a wild bird food store.

Leaves turn yellow in fall.

The Romance Series

The Romance series are a group of five named sour cherry cultivars that have a bush habit. All five, when fully ripe, are sweet and productive. They are a cross between Northern Europe sour pie cherries and Mongolian cherries that give each cultivar their excellent winter hardiness.

Romeo – Prunus x kerrasis ‘Romeo’ Zone 3

Height: 2 m. Spread: 2 m. Dark red fruit that increases in sweetness the more it ripens on the tree. Ripens in early August. Very good for fresh eating. Will produce fruit about one year before other cultivars.

Juliet – Prunus x kerrasis ‘Juliet’ Zone 2

Height: 2 m. Spread: 2 m. Excellent for fresh eating. Ripens in early August. Burgundy red fruit when ripe. Blooms a few days before other varieties and goes into dormancy earlier as well.

Valentine - Prunus x kerrasis ‘Valentine’ Zone 2 Height: 2.5 m. Spread: 1.8 m.

Bright red fruit. Most productive of the dwarf sour cherries. Fruit remains dark red when dried.

Cupid – Prunus x kerrasis ‘Cupid’ Zone 2

Height: Over 2m Width: 2 m.

Blooms a little later than other varieties. Produces the largest fruit of the Romance series. Cherries taste quite tangy. Fruit ripens to deep purple; black in early August. While the largest cherry, the fruit set is low so yields are about half of other varieties/cultivars.

Crimson Passion – Prunus x kerrasis ‘Crimson Passion’ Zone 3

Height: 1.2 m - 1.5 m. Width: 1.2 m – 1.5 m

Dark red cherries that are wonderful for fresh eating, pies, muffins crisps and cobblers.

Bonus: Rarely suckers! An excellent cherry for urban gardens.

FYI: Fully ripe Romance sour cherries are very high in antioxidants.

Thank you to the University of Saskatchewan Fruit Program.