Sour cherries, plums, and the fruits that skip sweet cherries
Why apricots and sweet cherries fail often, which sour cherries and plums are worth planting, and where peaches actually belong.
Stone fruit is where optimism goes to freeze. The trees are hardy enough, in many cases, to live for years. The blossoms open before the last frost is finished, and the crop vanishes.
If you want fruit more than you want a cloud of pink flowers, plant the later-blooming and the shrubby members of this group, and plant the early-blooming ones only where the station history says they have a chance. The mechanism is on the chinook and fruit-bud page. This page is the crop list that follows from it.
Sour cherries are the home crop
Montmorency is the standard pie cherry, a full-size tree that needs space and a partner or a second tree depending on the strain you buy. Ask whether your tree is fruitful alone.
North Star and Meteor are smaller sour cherries bred for cold climates, easier to fit in a yard and easier to cover on a bad night. Evans, also sold as Bali, is a very hardy sour cherry used on the northern plains.
These are the cherries to plant in a late-frost town. They still lose a crop in a bad May. They do not lose it as a lifestyle, the way sweet cherries do.
Sweet cherries, Bing and its relatives, want a milder spring and often a second cultivar for pollen. On the Front Range and in the high plains they bloom into frost.
In a warm Utah valley or a protected Western Slope site they can be a crop, and they can also be a bird feeder. If you plant them, net them, and do not make them your only fruit. Sour cherries are less interesting to some birds and more interesting to a cook.
Plums: bloom time is the split
Japanese-type plums and many hybrids bloom early, with the peaches, and they take the same frost. European plums bloom later.
That single difference is why a Mount Royal or a Stanley-type European plum crops in years when a Santa Rosa type does not. Toka and Superior are hardy hybrid plums with a prairie record.
They still want a pollinizer. Read the nursery tag for which cultivar pollinates which. A lone plum in a new yard is often an ornamental.
Plums in alkaline clay will show the same iron chlorosis CSU lists for stone fruit generally. Drainage and modest water help. A plum in a lawn, with the trunk buried in mulch, gets mower blight and vole damage and then looks “unhealthy” for reasons that have nothing to do with the cultivar. Plant it in a mulched circle, flare visible, mesh around the trunk.
Peaches and apricots, only in the right valleys
Apricots bloom so early that a Front Range crop is a bonus year, not an expectation. The tree can be healthy and decorative. Buy it for the flowers if you want flowers.
Do not buy it as the plan for jam. A late frost after bloom is the normal year, not the unlucky one, wherever your 1-in-10 late 32°F date falls in May and the tree bloomed in April.
Peaches belong where the climate already grows them. The Grand Valley, including the Palisade country, has a freeze calendar and a fruit industry that Denver does not. NOAA’s median last 32°F date at Grand Junction’s Walker Field is April 25, and the local siting of orchards does the rest.
A backyard peach in a Front Range frost pocket is a different project. It can ripen fruit in a kind year if the cultivar is early and the site is on a slope, and it can lose the crop the next three.
Dwarf peaches on a south wall can be covered. That is a hobby with a blanket, and it is legitimate if you name it honestly.
It is not a recommendation for Cheyenne, Laramie, Butte, or a June-frost mountain town. The University of Wyoming median at Laramie is June 7. The tree may live. The crop will not be why you planted it.
Nanking cherry (Prunus tomentosa) is the bush compromise. It is a hardy shrub cherry, often more reliable than a sweet cherry tree, pretty in bloom, and small enough to net.
It is not a sweet Bing. It is fruit you can actually pick in a cold yard. Plant two if the source says they fruit better as a pair. Give them sun and drainage.
Care that keeps the tree in the game
Full sun, slope or bench, no frost pocket. Wide planting hole, flare at grade, the method on the tree page. Water deeply the first summers, then less.
Stone fruit splits and gets disease in chronically wet ground, and it chloroses in wet alkaline ground.
Those are opposite-looking problems with a shared bad habit: a lawn sprinkler on the trunk every day.
Prune in late winter on a dry day, or follow the local extension note if bacterial canker has been a problem and they want a different season. Do not leave a flush of nitrogen on these trees.
Soft growth invites winter injury and disease. Thin peaches and large plums so the branches do not break and the remaining fruit has flavor. A tree with a thousand marble-sized peaches has not done you a favor.
Birds and hail take what frost spared. Net a small tree.
A hail frame over two bush cherries is more sensible than a net over a forty-foot sweet cherry you cannot pick. Deer browse the young wood.
Fence before you plant if deer are in the yard. Rabbits girdle trunks at snow line. A mesh cylinder is cheaper than a new tree.
Chill, bees, and the years the wood lives
Stone fruit also needs winter cold to break dormancy, and on the warm edge of the region, in a low Utah valley or a mild Grand Valley site, a cultivar bred only for a very cold prairie may not be the best match. The failure there is uneven bloom, not a frozen blossom.
Ask the nursery for a chill range that fits your winter, and do not assume the hardiest name is the right name in St. George or Moab. In Cheyenne, Butte, and the high valleys the problem is the opposite, and the hardy names are the ones that keep their wood.
Bees still have to fly. A sour cherry against a windy corner will bloom later than an apricot and still fail if the only warm afternoon is too windy for pollinators.
The porous wind protection that calms a vegetable bed calms a fruiting shrub too. Do not enclose the tree so tightly that bees cannot find it. A hedge with gaps is the right compromise.
When the wood itself dies back, look at the previous January before you blame the cultivar. A chinook that pushed buds, followed by a hard cold, kills twigs that were hardy on paper. White trunk protection and a site that is not the hottest south wall reduce that swing.
If the same tree loses wood most winters and blossoms most springs, it is the wrong species for the site. Replace it with a currant or a sour cherry on a slope, and stop replanting the apricot in the same hole.
Checklist
- Plant sour cherries before sweet cherries unless your valley has a real record with sweet cherries.
- Prefer later-blooming European plums over early Japanese types if spring frost is your usual loss.
- Treat apricots as flowers first and fruit second.
- Plant peaches where the freeze calendar and the local industry agree, or as a small covered hobby, not as a staple.
- Try Nanking cherry where a tree cherry has already failed.
- Keep the flare visible and the trunk meshed.
- Limit nitrogen and waterlogged soil.
- After two lost crops, change species. The site has told you something.
Apples may still be the better tree. They are on their own page. Small fruit may be the better use of the square footage.
That is not a demotion. It is how mountain gardens actually fill a bowl.
Sources
- NOAA NCEI Colorado freeze-occurrence table, Grand Junction Walker Field and the Front Range stations discussed on the calendar pages.
- University of Wyoming Extension spring freeze table, Laramie median.
- USU Extension, on bench sites versus valley frost pockets.
- University of Idaho Extension, BUL 859, on choosing fruit cultivars that mature early and bloom later where spring frost is likely.
- CSU Extension, Iron Chlorosis of Woody Plants.