Why Olive Trees in Redlands Are Shedding Pollen Right Now - And What That Means for Your Landscape
If you’ve gone outside in Redlands this week, you may have noticed a yellow coating of dust covering your car, patio furniture, and other areas around the yard. That is olive pollen and we’re in peak season for it right now.
As arborists rooted in the Inland Empire, we at Cambium Tree Experts pay close attention to bloom cycles of our trees. They alert us on various physiological factors including knowing when to fertilize, what pests to expect soon, along with how well the hormones are functioning within the tree, one of the tools we can use to assess the tree’s health an vitality.
Right now olive trees (Olea Europea) across Redlands are entering full bloom, signaling an important phase in their growth; and for property owners, an opportunity to take stock.
Why Are Olive Trees Blooming Now?
Olive trees require a combination of winter chilling hours and early spring heat accumulation to trigger flowering. Olive trees need about 2 months of dry cool weather below 50 degrees to flower properly. If the winter is warm with little to no chill hours, the tree may not enter its normal dormancy phase or produce as many flower buds. Since last November, according to the UC Davis Chilling Hours tool by city, our area has received around 300 chilling hours. Olive trees require 200 to 600 chilling hours depending on their variety. Varieties from Northern Africa and the Eastern Mediterranean region typically require fewer chilling hours while Southern European varieties from areas like Spain, require higher chilling hours for ideal production. As average daytime temperatures begin to rise to between 65 and 75 degrees, we start to witness flowering of olive trees. After a relatively mild winter and warm March, many Redlands olives are blooming in sync this year.
The trees release huge amounts of fine pollen that gets dispersed by the wind. This explains the spike in allergy symptoms and dusty surfaces. The flowering phase lasts roughly 2 to 3 weeks and is a critical time for fruit production and future tree health.
What Should Property Owners Do During Bloom?
Here is what we’re recommending to our customers this week:
Don’t Prune Yet!
Pruning during bloom can reduce fruit set or cause stress to the tree. We recommend waiting until late May or early June, for desert areas like Palm Springs, this may be a bit sooner. Waiting until this time after the bloom finishes and fruit sets, will significantly help if you’re looking to reduce fruit drop.
Assess Vigor
This is a great time to assess the overall health of your olive trees by making some basic observations:
Are the leaves vibrant green or showing yellowing (chlorosis)?
Do you see dead branch tips or sparse canopy density?
Are suckers or water sprouts dominating the lower trunk?
If so, your tree may benefit from targeted fertilization, deep watering, or pruning to improve structure and airflow.
Manage Pollen and Debris
Olive pollen can build up in HVAC systems, fountains, and pool filters. A quick rinse-down of hardscape surfaces and maintenance of filters during bloom season helps reduce headaches later, both figuratively and literally.
Fruit or No Fruit? Your Call
If you’re not a fan of the mess olive trees create, you’re not alone. It’s a good time to consider fruit suppression options like Florel spray (applied right as flowers open) and timing of these products are crucial. Fruit suppression should always be done by a professional to ensure safety and efficacy.
Olive Tree Highlight: A Redlands Giant
We recently rechecked one of Redlands’ largest cultivated olive trees - standing at 46 feet tall and thriving. This tree is located near Redlands Country Club in the south part of the city. Trees like this are rare, but they serve as powerful examples of what mature, well-managed olives can become in our climate.
If you have a large olive or are curious about its growth potential, give us a call-we love encountering legacy trees.
Largest Olive Tree In Redlands
Need Help With Your Olive Tree? Let’s Talk.
We specialize in the care of mature olive trees and understand how to balance beauty, function, and health. Whether you want more fruit, less fruit, better shade, or just a cleaner yard - Cambium Tree Experts is here to help.
Call us today to schedule a spring assessment.
Let’s keep your landscape thriving!