Pear trees are one of the most resilient fruit trees you can grow, but there may be complications that cause them to lose their leaves or hinder foliage development.
Like other deciduous trees, pears shed their leaves in preparation for winter.
But, what if the leaves are falling, and it isn’t autumn? Or, what if springtime rolls around and the branches are still bare?
Here are the five main reasons why pear trees lose their leaves (aside from autumn):
- Poor Soil Conditions
- Dormancy Complications
- Human Interference
We will address each issue and provide solutions to help you resolve your leaf troubles.
Can Poor Soil Cause Pear Trees to Lose Leaves?
Pear trees thrive in moist, sandy-loam soil with proper drainage. Drowning roots or overly dry roots can lead to leaf loss.
Overwatering & Poor Drainage
Plants need both carbon dioxide and oxygen to live.
Plants require oxygen to metabolize food for growth. Waterlogged soil from overwatering or flooding prevents the root system’s access to oxygen. Compacted soil with a high clay content can deprive roots of oxygen as well.
This can lead to loss of foliage, and eventually, death.
You also don’t want the opposite problem- overly dry soil. This prevents trees from receiving nutrients which can cause leaf loss and death.
The University of Minnesota recommends watering pear trees weekly during their first year after planting. Once the roots grow deep, they require less watering. In particularly dry conditions, give the trees an occasional thorough soaking.
Which Pests Cause Pear Trees to Lose Leaves?
Common pests afflict pear plants and cause leaf drop, especially when they feed in overwhelming numbers. Determine which pests are common to your area and monitor for them.
Two pests to keep an eye out for are pear psylla and spider mites.
Let’s look at the effects of these pests and potential management methods.
Pear psylla is a flying insect with red eyes at every stage of development. They consume the living tissue of leaves and stems that carry plant sugars and can transmit pear decline (see next section) through their saliva.
- Premature leaf drop
- Dark, sooty mold from honeydew
- Stunted growth
- Damaged fruit
- Prune sufficiently every year to prevent excess tree growth. Psylla nymphs feed on new growth.
- Monitor psylla numbers to determine the degree of management necessary. The University of California goes into great detail on monitoring the populations.
- Remove suckers (small sprouts) on primary branches to maximize the effectiveness of pesticides and eliminate the additional food source.
- Apply dormant sprays during the winter and petroleum oil when leaves are present.
- Opt for soft pesticides during the growing season to keep beneficial insects alive. Harsh pesticides kill the psylla’s natural enemies.
Explore natural fruit tree insect control solutions (link to Amazon).
Several species of spider mites attack pear trees. They can be brown, red, yellowish, or white, but all are tiny and crawl on eight legs.
Spider mites eat leaf cells. In large numbers, spider mites can cause significant foliage loss.
- Stippling (numerous tiny spots) and discoloration of leaves
- Leaf drop
- Decayed and misshaped flowers and fruit
- Embrace natural management tools. Spider mite numbers are reduced naturally by cool, wet weather and beneficial insects such as ladybugs and minute pirate bugs.
- Keep trees well-watered and minimize dust with grass or mulch around tree bases. Spider mites thrive in dry conditions, so make the environment inhospitable.
- Employ chemical control. PNW Handbooks provides an extensive list of helpful sprays for dormant and growing seasons.
Which Pear Diseases Cause Leaf Drop?
There are a number of diseases that cause pear leaves to drop. Educate yourself on the harmful organisms your particular pear cultivars are susceptible to.
Let’s address two common diseases that can cause leaf drop: pear decline and fabraea leaf spot.
Pear decline is caused by an organism called phytoplasma which is spread by the pear psylla pest.
- Poor shoot growth
- Young shoot death
- Upper leaves redden and roll up
- Leaf drop
- Undersized leaves and fruit
- Use pear rootstocks resilient to pear decline.
- Manage pear psylla populations (see “Pests” section above).
- Keep fruit trees healthy and strong by supplying them with nutritious soil, full sun, adequate watering, and proper pruning.
Fabraea Leaf Spot (Leaf Blight)
The fungus Fabraea maculata causes Fabraea Leaf spot, which typically infects the foliage and fruit of pear trees during the latter phase of the growing season.
- Brown or black leaf spots
- Yellowing leaves
- Leaf drop
- Fruit lesions
- Small leaves and fruit
Discard all infected plant tissue. Prevent fungal infection by maintaining sufficient sanitation standards. Clean tools and discard plant debris. Apply appropriate fungicide sprays.
See Connecticut State’s fungicide guide for specific chemicals and when to spray them.
What if Pear Trees Don’t Grow Leaves in the Spring?
Pear trees enter a dormant state in winter to survive freezing temperatures. During dormancy, their branches remain bare and new leaves emerge in the spring.
If your tree doesn’t produce leaves in the spring, your tree could be dead.
Cut back the outer layer of bark on a small portion of the tree to see if the tissue underneath is green or brown. Green means alive; brown means dead.
If only certain branches are dead, prune away the dead branches.
Discard dead tissue to discourage the growth of pathogenic fungi.
Ensure your pear tree is zoned for your region as some cultivars are less winter hardy than others.
Keep in mind, even winter hardy trees can die or sustain winter injury from exceptionally cold winters and dramatic fluctuations in temperature.
To prevent winter injury in containerized plants, the University of Vermont recommends mulching roots, grouping plants together, or burying them in the ground.
Young pear tree trunks are delicate. The University of Minnesota recommends protecting them during winter in cold climates by wrapping the trunks in reflective material (source).
Wrapping tender trunks prevents sunscald, which occurs when sunlight melts frozen water in the trunk tissue. When the sun dips behind a cloud or the horizon, the water promptly refreezes, killing the tissue.
Are You Causing Pear Leaf Loss?
Sometimes, human interference with natural processes disrupts leaf production.
PennState asserts that pruning in the late fall or early winter before a tree’s dormancy can weaken a tree, making it more susceptible to winter injury.
Also, transplanting can cause stress for pear trees.
If your tree’s leaf production is limited following a transplant, know that it will take a year or two to show signs of new growth.
The Texas A&M Forest Service outlines ways people exacerbate the stress on a tree during transplanting, including rough handling and planting the tree below the soil line.
Lastly, take care to follow instructions when using pesticides and other chemicals. Do your research. Neem-based sprays are phytotoxic to certain pear cultivars.
I hope this helps you determine the underlying cause of your tree’s leaf loss and how to move forward.
Choose cultivars suited for your region’s climate and maintain their health with proper pruning, watering, well-draining soil, and sufficient sanitation to promote normal foliage patterns.
If you run into trouble with pests or diseases, or if you require plant tissue or soil testing, consider reaching out to a local extension office for further region-specific advice and tests.
Related Reading: Is Pear a Fruit? Facts and Misconceptions
Buy pear trees online (link to Nature Hills Nursery)