Cherry trees are known for thriving in temperate regions with cold winters. Their breathtaking spring blooms and sweet summer fruits make them a favorite backyard tree for gardeners around the world. But what about those living in climates with hot summers and mild winters? Can cherry trees grow in hot climates where temperatures soar during the summer months?
What Types of Climates Do Cherry Trees Prefer?
To understand if cherry trees can tolerate hot climates, first we need to examine the native habitat and ideal growing conditions for these deciduous fruit trees.
Native Climate Needs
Cherry trees originated in parts of Europe and Asia with four distinct seasons. Wild cherries can be found growing across a large range, from the Mediterranean region to the cold temperatures of the Tibetan plateaus.
Most varieties require a cold winter period to trigger the growth cycle in spring. The flowers bloom just as warmer weather arrives.
Optimal Temperature Ranges
While native cherry trees are adapted to cold winters and freezing temps, most prefer warm, sunny summers over hot and humid ones.
Ideal daytime summer temperatures generally range from 70°F to 90°F (21°C to 32°C). As a cold-natured fruit tree, excess heat can disrupt the growth and productivity of cherries.
Chill Hour Requirements
In addition to specific temperature parameters, cherry trees need to acquire winter chill hours for fruit production. This means being exposed to cold winter temperatures between 32°F to 45°F (0°C to 7°C) for a cumulative number of hours.
Chill hours needed for common cherry tree varieties
The required chill hours help promote uniform flowering and fruit set. It triggers important physiological changes within the tree.
Without fulfilling winter chill requirements, cherry trees struggle to break dormancy and bloom properly in spring. Lack of cold weather leads to erratic or reduced yields.
Humidity Concerns
Most cherry varieties also prefer relatively dry air over tropical or sub-tropical humidity levels. Wet weather during bloom time can inhibit pollination and lead to fungal diseases like brown rot.
Prolonged high humidity interferes with fruit quality development too. It causes split skin, accelerated spoilage, and increased pest pressure.
Can Cherry Trees Survive Hot Summer Temperatures?
Now that we know the preferred climate specs for cherry trees, how do hot temperatures factor in? Can they withstand and remain productive if summer heat is intense or extreme?
Defining Hot Climates
First, let’s clarify exactly what constitutes a “hot climate.” In general, areas with extremely high summer temperatures, extended heat waves, and warmer overnight lows fall into this category.
But the definition depends somewhat on the peak temperatures that local cherry tree varieties are conditioned to. Daytime summer highs over 100°F (38°C) would be considered a hot climate for most.
Impact of Heat Stress
Excessive warmth outside of ideal temperature parameters taxes a cherry tree’s physiology. It causes the vascular system to breakdown and inhibits photosynthesis.
Prolonged heat stress also interferes with fruit development, reduces fruit size and quality, and can lead to sunburn damage on leaves and branches.
If daytime highs surpass 105°F (40°C) it can literally bake tender cherry leaves and slow growth. Extreme summer heat puts considerable strain on the tree.
Tolerance By Variety
Some cherry varieties are bred to withstand warmer summertime temperatures than others. Much depends on where the tree varieties originated and their genetic makeup.
As a rule, cherries native to cooler mountainous regions or farther north have lower heat tolerance. Types bred in hotter cherry-growing regions of Europe and Asia perform better.
Duke cherries and Royal Ann (Napoleon) tend to tolerate more heat stress without loss of productiveness. Whereas Empress Eugenie, Lapins, and Sweet Heart are less suited for punishing temperatures.
Heat hardiness of popular cherry tree varieties
Protective Measures
Aside from selecting hardy varieties, other protective steps can be taken to help cherry trees cope with hot climates:
- Providing afternoon shade
- Mist spray irrigation
- Painting tree trunks white to reflect heat
- Wrapping foliage with shade cloth
- Careful summer pruning
- Mulching roots
Taking steps to minimize heat stress gives cherry trees their best odds to endure and remain productive during hot spells.
Will Cherry Trees Fruit in Hot Climates?
Many cherry varieties need sustained winter chill to blossom and fruit properly. Lack of adequate chill hours prevents flowering altogether or causes erratic blooming in spring.
This is why historically, most cherry orchards are located in zones with cold winters. But modern advances are changing that.
Chilling Requirements
As covered earlier, to set fruit successfully cherry trees must accumulate a number chill hours below 45° F (7° C) over the winter months.
- Short-hour varieties need as few as 200-400 hours
- Long-hour types require up to 1600 hours
When chill hour needs go unmet, trees either remain dormant or flower sporadically.
Insufficient Chill Effect
With warming winters becoming more common globally, problems with inadequate chill are increasing. This negatively impacts productivity of cherries and other tree fruit.
Lack of cold weather causes confused timing and physiology within trees. Rather than uniform blossoms, they flower erratically with some buds remaining closed. Pollination also suffers.
The result is reduced fruit set or complete crop failure.
Low-Chill Variety Breakthroughs
In response to lack of winter chill, horticulturists are fast-tracking development of new “low-chill” cherry varieties. These trees need as little as 100-500 chill hours.
Breakthrough low-chill cherries like ‘Pink Dawn’ and ‘Scarlet Royal’ are expanding options for gardeners in Zone 9 and warmer. They can produce abundant flowers and fruit despite winters with only limited cold spells.
Best Cherry Tree Varieties for Hot Climates
For the best chance of success growing cherries in hot climates, concentrate on varieties bred specifically for such conditions. Look for low-chill types marketed for warm winter regions.
Low-Chill Southeast Varieties
Public universities in Florida, Georgia and South Carolina have cherry breeding programs for warmer zones. Varieties they introduced include:
- Florida Grande
- Southland
- Byrd Cherry
- Scarlet Royal
These tolerate heat well while needing only 200-400 chill hours.
Low-Chill Hybrids
Private growers are also hybridizing less common cherry species with cold-hardy flowering types. This allows reliable harvests in short-winter locations.
- Carmine Jewel – Rainier and Korean cherry cross
- Pink Dawn – Japanese hill cherry hybrid
- Sweet Southern – Barbados cherry and Chinese cherry mix
These exciting new cherry varieties are expanding options for hot climate regions with moderate winter chilling.
Providing Optimal Growing Conditions
To help cherry trees cope in hot climates, it’s critical to give them the best care possible. Pay close attention to other cultural inputs which support and sustain growth.
Site Selection
Choosing the right planting site makes a tremendous difference in tree health. Pick a spot with:
- Full sun exposure
- Well-drained, loamy soil
- Some air flow and circulation
Avoid compacted, soggy, or alkaline soils. These inhibit root function which leaves trees prone to heat stress.
Amend soil prior to planting as needed to meet cherry requirements.
Adequate Irrigation
Especially during first years, don’t let newly planted trees dry out. Water thoroughly keeping root zones moist but never saturated.
As they mature, established cherry trees need about 30 inches of annual water depending on hot climate dynamics. Time irrigation to provide their deepest requirement during summer.
Sun and Shelter
Cherries need a minimum 6-8 hours of direct sun daily during the growing season. But extra shade, especially in peak afternoon can give relief from extreme heat.
Trees do well when under-planted below mature orchard companions like pecans which filter intense sunshine. Other shade trees and shelterbelts also moderate exposure.
Soil Enrichment
Use compost and organic matter to enhance drainage and nutrition in the root zone. Fertilize trees in early spring being careful not to overstimulate growth right before summer.
Proper Pruning
Strategic pruning improves air circulation and light penetration within the tree canopy. Remove inward-facing branches and dense interior growth to optimize airflow.
Prune to shape young cherry trees. Then focus summer pruning mainly on water sprouts and suckers.
Removing a portion of top growth helps shorten buds, encouraging outward growth the next season. Never heavily prune right before winter.
Protect Trunks
Painting cherry trunks white reflects sunlight rather than absorbing heat from direct exposure. Other light colors work too.
Alternatively wrap trunks with commercial tree wrap or burlap strips to shield from southwest sun. Remove trunk protection during winter months.
Cold Protection
Ironically, while dealing with hot summers, mild winters can also be problematic for cherries in warmer zones. Temperatures consistently dipping below freezing help promote next year’s flower buds.
Where winter cold fails to accumulate, temporary emergency blankets, low tunnels, and frost alarms can help protect blossoms when chill events do occur.
Pest Prevention
Unfortunately cherries attract their share of insect pests and diseases. These problems tend to accelerate in hot, humid weather.
Fungicides and organic sprays applied at bloom and fruit set prevent loss of crop to rot. Keep trees pruned for air flow and practice sanitation.
Monitor for common cherry pests like aphids and leafhoppers which thrive in warmer areas. Use integrated pest management relying on least toxic remedies.
Protecting Trees from Temperature Extremes
Balmy spring weather quickly shifting to blazing heat waves creates additional challenges for cherries in transitional climates. Special measures to shield trees from these temperature extremes improves outcomes.
Safeguarding Against Sunburn
Rapid day-to-night flux during early season makes tender growth susceptible to sunscald damage. When heat spikes abruptly, take steps to shield foliage and scaffold branches until they harden off.
Methods include:
- Commercial tree wraps
- Temporary shade cloths
- Foliar protectants and reflective sprays
Preventing Heat-Drought Stress
Sudden hot spells which spike temperatures to 10+ degrees over normal bridle transpiration rates in leaves and shoots. Moisture evaporates before roots can absorb enough to replenish needs.
Rapid-onset heat waves literally dry out distal parts of the trees from the top down. Leading to leaf necrosis, twig dieback and aborted fruit.
Where heat spikes occur, increase irrigation immediately to help equalize moisture levels before desiccation damage sets in. Prioritize afternoon shade and misting too.
Safeguarding Pollination
Spring heat waves also endanger pollination success. Ideal conditions for cherry flowers to be receptive to pollen transfer range from 57° to 70° F (13°- 21° C).
A spike over 80 degrees will prevent fertilization during bloom. And temperatures above 85° F (29° C) will kill flower ovule viability.
When forecasts show early season heat events during flowering:
- Drape protective shade cloth
- Use anti-desiccant foliar sprays
- Increase hive strength for adequate pollination
Cold Protection Again…
The first season after planting is perilous for cherry trees in hot winter climates. While surviving summer, inadequately chilled specimens remain vulnerable to random cold snaps before they fully acclimate.
Be prepared to deploy emergency cold intervention tactics as needed through the first couple winters. Don’t let seasonably warm trends create a false sense of security.
Conclusion – Cherries Can Work in Hot Zones
To conclude – yes cherry trees can grow productively in hot climate conditions given careful variety selection and appropriate cultural methods. Thanks to intensive breeding programs, low-chill cherry varieties unlock potential for home orchards much farther south.
These breakthrough trees evolved to thrive across a spectrum of unfavorable dynamics – from marginal chill hours to punishing heat waves. However, success ultimately depends on implementing protective practices tailored to interpreting and responding to signals from the trees and orchard environment itself.
The most reliably productive cherry growers embrace season-long vigilance. They adapt care strategies to safeguard trees from climatic variability. Partnering with climate-compatible cherry varieties, continuing advances offer gardeners in the warmest zones exciting new potential.
