Cherry

Fresh, sweet cherries are delicious, but cherry trees can be difficult to grow.

According to UC California Backyard Orchard, “cherries are the most difficult trees to keep alive.” If you are still determined, let’s see what we can learn about these trees.

People have been enjoying cherries since prehistoric times. Cherries are stone fruits, which means the fruit is a drupe. There are two types of cherry trees: sweet (Prunus avium) and sour (Prunus cerasus). The two cannot cross-pollinate with each other. Both types are native to Europe and western Asia. Sweet cherries are also known as wild cherries or gean.

Prunus cerasus (Diako1971) CC BY-SA 4.0

How to grow cherry trees

Cherry trees cannot tolerate soggy ground and they need a lot of sunlight. Excellent drainage is critical. So much so, that cherry trees are generally planted on mounds, or berms. Trees should be spaced 14 to 20 feet apart, and you are going to need at least two because most sweet cherry varieties require cross-pollination to bear fruit. Sour cherries, the type used in pies and preserves, are self-fertile and do not require cross-pollination.

While installing bare root stock is preferable, you can grow a cherry tree from a pit. The pit will need to be exposed to cold temperatures (stratification) before it will germinate. When selecting a cherry variety for your landscape, be sure to choose one with a chilling requirement that matches your microclimate. The tree will set fruit in 3 or 4 years.

Seasonal care for cherry trees

Each winter, you will need to prune out 10% of the previous year’s growth, as well as any dead, damaged, diseased, or crossing/rubbing branches. You will also want to apply dormant oil. An application of fixed copper can help reduce bacterial canker (gummosis). In spring, as blossoms appear, apply a fungicide, such as Bordeaux mixture, to control brown rot, and feed each tree 2 lb. of urea or 70 lb. of aged manure just before a deep watering.

Birds will enjoy your cherries long before you do if you do not protect your crop with netting or a tree cage. Trees will need to be drip irrigated every day in summer, or given 3 to 5” of water every 2 or 3 weeks. After harvesting your cherry crop, feed each tree with 2 lb. of urea and irrigate right away. Keep trees irrigated regularly until September, then stop watering altogether. This will help prevent root rot.

Cherry pests and diseases

It is astounding to learn how many diseases and insect pests can interfere with growing cherries. If birds, squirrels, and pocket gophers weren’t bad enough, cherry trees are are regularly attacked by a wide variety of insect pests:

• borers: American plum, Pacific flathead, peachtree, peach twig, and shot hole borers
• flies: fruit flies and western cherry fruit flies
• leafhoppers: cherry and mountain leafhoppers
• leafrollers: fruittree and obliquebanded leafrollers
• mites: brown, European red, and webspinning spider mites
• moths/caterpillars: orange tortrix, oriental fruit moth, redhumped caterpillar, spotted wing drosophila, and western tussock moth
• scale: brown apricot and San Jose scale

Black cherry aphids, cherry slugs, earwigs, green fruitworms, western flower thrips, nematodes, and cribrate weevil can also be added to that collection. And the list of cherry diseases is no less daunting:

• bacterial: canker, crown gall, X-disease (cherry buckskin)
• fungal: armillaria root rot, botrytis blossom, blight, brown rot and twig blight, cytospora canker, Eutypa dieback, phytophthora root and crown rot, powdery mildew, ripe fruit rot, wood-decay
• viral: cherry mottle leaf, cherry rasp leaf, cherry rugose mosaic, prune dwarf, tomato ringspot

Cherries are also susceptible to a genetic disease, called leaf crinkle, and a couple of mysterious diseases, called cherry necrotic rusty mottle and cherry stem pitting, that occur when grafting scions. Applying sticky barriers to the trunks of trees can block crawling insects, but it does nothing against flying insects.

Bottom line: cherries are probably best left to the professionals. Hopefully, this information will help you appreciate just how much effort goes into providing these delicious summer treats. If you decide to give cherries a try, please share your experience with us in the comments!