Cherry trees can be grown successfully across Pennsylvania, but success relies on informed variety selection and proper site preparation. While the state’s climate meets the chilling requirements for fruit production, it also presents challenges like late frosts and high humidity. Planting the right cultivar in a location that mitigates these environmental stresses is essential for a bountiful harvest.
Understanding Pennsylvania Climate Zones
Pennsylvania’s climate falls within USDA Hardiness Zones 5a to 7b. Tree selection must align with the specific zone of the planting site to ensure winter survival and reliable fruit set.
All cherry trees require a sufficient period of cold temperatures, known as chilling hours, to produce fruit. Cultivars typically need between 800 and 1,200 hours of temperatures between 32°F and 45°F during the dormant winter period to break dormancy. Pennsylvania generally provides these necessary hours throughout the state.
The main climatic challenge is the combination of late spring frosts and high summer humidity. Sweet cherries blossom earlier and are highly susceptible to frost damage, which can eliminate the harvest. Tart cherries are significantly more cold-hardy and bloom slightly later, making them a more reliable choice for the variable spring weather found throughout Zones 5 and 6.
Recommended Cherry Varieties for Pennsylvania
The most dependable choice for nearly all Pennsylvania gardeners is the Tart Cherry (Prunus cerasus). These trees are hardier and more resistant to the diseases that thrive in the humid Northeast environment. The most widely recommended variety is ‘Montmorency,’ which is highly productive, cold-tolerant, and naturally self-fruitful.
Another excellent tart option is ‘Balaton,’ a Hungarian cultivar known for its dark, firm flesh and high sugar content, which is also self-pollinating.
Sweet Cherries (Prunus avium) are better suited for the warmer Zones 6 and 7. While most traditional sweet cherry varieties require a compatible pollinizer, selecting self-pollinating varieties like ‘Stella’ or ‘Lapins’ is highly advisable to ensure fruit set. Planting sweet cherries on dwarfing rootstocks, such as Gisela 5, can make the trees smaller and easier to manage.
Essential Soil and Sunlight Requirements
Cherry trees demand a planting site that receives full sun, defined as a minimum of six to eight hours of direct sunlight daily. This high light exposure is necessary for fruit development and helps reduce the likelihood of fungal diseases by quickly drying morning dew. Choosing a location with good air circulation also helps prevent the establishment of pathogens.
The most important soil requirement is excellent drainage, as cherry roots are highly susceptible to root rot in waterlogged conditions. Heavy clay soils should be avoided or amended substantially with organic matter to improve porosity. The ideal soil is a well-drained sandy loam with a slightly acidic to neutral pH range, ideally between 6.0 and 7.2.
Planting is best done in early to mid-spring, as soon as the soil is workable, or in the fall. When placing the tree in the ground, ensure that the graft union remains one to two inches above the surrounding soil line. This practice ensures the desired fruiting variety does not sprout roots, which would bypass the benefits provided by the rootstock.
Managing Regional Pests and Diseases
The humid climate of Pennsylvania creates an environment where fungal diseases pose the largest threat to cherry production. Brown Rot is a major concern, as it attacks both the blossoms in the spring and the developing fruit near harvest, causing them to turn brown and shrivel. Cherry Leaf Spot (Blumeriella jaapii) is another common pathogen that causes purple or reddish-brown spots on leaves, leading to premature yellowing and leaf drop that weakens the tree over time.
Specific insect pests also require preventative attention in the region. The Cherry Fruit Fly lays eggs just under the skin of ripening fruit, and the resulting larvae, or maggots, ruin the harvest. Black Cherry Aphids feed on young leaves, causing them to curl and stunt, which can reduce the tree’s overall vigor. Preventative fungicide and insecticide sprays, timed correctly with the tree’s bloom and fruit development stages, are often necessary for a successful harvest.
Finally, growers must contend with local wildlife, particularly birds, which are highly attracted to the ripening fruit. The most effective non-chemical method for protecting the crop is to cover the trees with fine-mesh netting just as the cherries begin to change color. This physical barrier is necessary to prevent birds from consuming the entire harvest before it can be picked.