4 Reasons Why Olive Trees Grow Best In Full Sun
Olive trees are an absolute staple of Mediterranean cuisine. And, as more people take time to garden and grow their own food, olive trees are rising in popularity. Based on the climates they’re native to, you might be wondering if you can grow your own.
If you’re going to grow an olive tree, you must plant it in full sun. Olive trees are originally from warm, sunny parts of the world. They need the sun to grow olives, a lack of sun leads to a lack of blossoms, sunlight keeps olive trees healthy, and olives won’t ripen without proper sun.
Let’s take a more in-depth look at all the reasons why you should grow olive trees in full sun. Not only that, but we’ll also look at the different requirements for properly growing olive trees, and give you some tips on how to best plant them!
1. Olive Trees Need Enough Sun To Grow Fruit
There are plenty of types of trees that can still grow fruit without intense, full sunlight. With that said, olive trees are not one of them.
While they will also need the proper water and nutrients, the most important component for a bountiful olive harvest is intense, unfiltered sunlight.
All plants use some amount of light for photosynthesis. This is the process in which plants use sunlight and convert it into sugars that they need to grow and process crucial nutrients from the soil.
What Happens When An Olive Tree Doesn’t Have Direct Sun?
Without enough sunlight, olive trees simply do not have the extra energy to put into growing olives. Because olives are where the tree’s seeds are contained, they are actually entering the reproductive stage of their growth when they produce olives.
If plants don’t have extra resources to put into their reproductive stage, they’ll devote the available energy to the preceding stage. That is the vegetative stage.
The vegetative stage is when a plant spends all its resources on its foliage. By growing more leaves, and expanding their leaves, the plants also hope to increase their ability to gather more sunlight.
In short, full sunlight allows your olive tree to dedicate the resources it needs to the reproductive stage- when it grows the olives.
All in all, a lack of sunlight will severely impact your olive tree’s growth. If you’re interested in how long olive tree’s normally take to grow, take a look at our full olive tree timeline laid out!
2. Olive Trees Can’t Form Blossoms Without Sunlight
Before an olive tree even begins to produce olives, it has to go through the proper steps first. As we mentioned, growing olives are part of the reproductive stage of an olive tree’s life.
But there’s another critical part of the olive tree’s reproductive stage: growing flowers and blossoming. Then the flowers need to be pollinated before the next stage (growing olives) begins.
However, blossoms may not even begin to grow if your olive tree isn’t getting enough sun. Or, perhaps equally as disappointing, your olive tree might begin to form flower buds, only to have them drop.
Why Would An Olive Tree Drop Its Blossoms?
This is commonly referred to as blossom drop. It can happen for a variety of reasons, and often it’s as a result of an imbalance (or deficiency) of certain micronutrients.
When it comes to blossom drop though, it isn’t always because of a nutrient deficiency. That’s especially true when it comes to subtropical plants that need a lot of sunlight, and that includes olives trees.
3. Sunlight Keeps Olive Trees Healthy
Olives trees need more sunlight than your typical house plant to stay healthy. Even if olive trees appear to be healthy, that doesn’t necessarily mean that they are.
In fact, no matter how the tree looks, if the olive tree isn’t getting enough sunlight it’s almost impossible to keep it happy and healthy.
This applies to olive trees grown both indoors and outdoors. If you plan on growing your olive tree indoors, it’s especially important to make sure you can give it enough light year-round.
There are a lot of different ailments that can arise as a consequence of olive trees not getting the proper amount of sunlight.
Even before olive trees reach the stages where they produce blossoms and subsequently, olives, they have to “bulk up,” so to speak.
What Happens If An Olive Tree Does Not Receive Enough Sunlight?
In the earlier stages of their lives, these trees are focused on growing vegetation to allow them to collect more sunlight, which then means that they can create more plentiful energy stores.
Remember, sunlight is a crucial ingredient in the process plants use to feed themselves.
If a plant isn’t getting enough sunlight, chances are it also just plain isn’t able to feed itself. And any organism without some kind of food supply simply cannot sustain itself.
4. Olives Won’t Ripen Without Proper Sun
Even if your olives do begin to grow, that doesn’t guarantee you a successful harvest. The tree’s work isn’t done until the olives are ready to be harvested.
Even after producing the initial fruit onset, there’s still plenty that the tree needs to do before the olives reach their full size and flavor.
If you are seeing olives on your tree, but they don’t seem to be making much progress, you may need to assess whether or not your olive tree is actually getting enough sunlight.
Here is a timeline of olive tree growth. It can help you know if your olive tree is developing at a normal rate!
What If The Olives Are Not Ripening?
If you’re growing your olive tree in a container, this is a much simpler issue to solve, especially if you’re growing it outdoors.
Take a look at the space you have for growing. If the area you have your olive tree in seems to have some shady spots during the day, you may need to move it.
Try to find an area that gets the most sunlight during the day. This may mean you need to observe the area several times throughout the day. Make sure that the spot you’re scoping out is also free of obstructions that could block sunlight from getting to your tree.
Of course, there’s nothing you can do about a cloudy day, but those will happen anywhere.
Possible obstructions can include:
- Other plants and trees
- Large vehicles
- Garden and patio furniture
- Fences and retainer walls
- Homes, decks, and sheds
This is just a partial list, but the principle is clear. Make sure there’s nothing getting in the way of your olive tree’s shade.
What If You Can’t Move Your Olive Tree?
That can be a slightly more difficult problem. If your tree is already established, move anything that blocks the sun, and consider trimming other trees if they’re getting in the way of your tree’s light.
Another important note: If you’re worried about your olives reaching their full potential, you also need to make sure they get enough water. In a study from The Journal of Horticultural Science and Biotechnology, even with the same amount of sunlight, olive trees that have full irrigation (versus drip irrigation) produce a higher weight of fruit produced.
How Much Sun Does My Olive Tree Need?
Saying that olive trees need a lot of sun is one thing. However, to some people, 6 hours seems like a lot of sunlight, whereas other people might think full sun means a full 12 hours of unfiltered light.
How much sun does an olive tree need? Olive trees thrive on sunlight, and that means that six hours of sunlight is an absolute minimum. When you want a good harvest, you don’t want to do the minimum requirements for any of your tree’s care. Aim for a minimum of 8 hours of intense, unfiltered sunlight for your olive tree.
If you can, it’s even better to make sure your olive tree gets up to 10 or 12 hours of sun.
Granted, this may not be possible in all regions. And if it’s not, remember, the more sun you can give an olive tree, the better.
How To Make Sure Your Olive Tree Gets Enough Sun
As we reviewed above (in reasons to plant your olive tree in full sun), you should be carefully selecting the area in which you’ll place your olive tree. Along with that, you can also do your best to remove any obstacles preventing the sunlight from reaching your tree.
However, if you haven’t planted your olive tree yet, there’s a more precise way to check out the quality of sunlight in a given area.
A light meter is incredibly helpful when you need to check out an area for growing a plant with very high light requirements.
For plants like olive trees, we recommend using a light meter like the Dr.meter LX1330B Digital Illuminance Light Meter. Now, if you’re wondering why we chose this meter in particular, it’s because not only is it easy to use, but it also does the work for you.
Yes, it includes the ability to record and store data, meaning that you don’t need to babysit it and take recordings all day. Just set it in the spot and let it record, and check it at the end of the day.
Can I Grow An Olive Tree Indoors?
Yes! However, your two main concerns with growing an olive tree inside are: making sure that you have a large enough planter for your olive tree and making sure your olive tree gets enough light.
If you want to grow an olive tree in the house, you need to make sure that there’s a large window nearby that gets plenty of sun. Even then, you may struggle to ensure that your olive tree is getting its daily dose of full sun.
It’s perfectly fine to supplement the light your olive tree gets, even if it’s not from natural sunlight.
Of course, natural sunlight is the preferred option, and it’s totally free. However, you can make sure your tree is happy and healthy by using lights to supplement natural light. Before you ask, no, a desk lamp or ceiling lights will not help.
What Type Of Supplemental Light Is Best?
Not only is the amount of light produced by incandescent light bulbs insufficient, but it also doesn’t contain the light spectrum needed. A lot of growers use HID (high-intensity discharge) lights. However, they put off a lot of heat, and you’ll also need to switch bulbs to get a full spectrum.
Instead, we recommend a full spectrum LED lighting setup. The advantages of these are endless. You can choose the kind of light to give your tree, and they use very little energy while also producing very little heat.
In all fairness, if it’s your first time using a grow light (the easiest term to find the proper lights for growing plants indoors), it’s not always easy to find the right one. To make it a little easier, we suggest this LBW Grow Light With Stand.
One of the first reasons is that it’s easy to set up, just like a normal lamp. Next, it has a few different light modes, and can even mimic the natural sunlight at its peak, around noon and the middle of the day. Plus, it comes with a timer, which is a serious benefit if you work away from home.
What Other Requirements Do Olive Trees Have?
It’s no mystery that olive trees can’t survive on ample amounts of sunlight alone. Of course, getting a good olive harvest also isn’t as easy as just watering your olive tree and making sure it gets plenty of light.
So, what do you need to grow an olive tree?
Here’s a quick overview of what olive trees need to grow:
- Plenty of water
- Full sun (6-12 hours a day)
- A regular fertilizer regimen
- The right soil
- Pest protection
- Maintenance pruning
- Only appropriate mulching materials
Next, let’s look at these factors a little more in-depth.
How To Water Your Olive Tree
Just because olive trees thrive in heat and plenty of direct sun, that doesn’t mean they’re also drought-hardy. In fact, it’s even more important to be vigilant about watering your olive tree than with other hot-weather trees.
Now, olive trees also need soil that drains well. If your soil tends to hold an excess amount of moisture, there’s a centuries-old trick you can use to your advantage.
Planting your olive tree on a sunny slope can help your tree get all the sun it needs, while the slope also helps extra water drain away. This takes care of part of the soil requirements.
For an in-depth guide for watering your olive tree, check out this guide!
Olive Trees Need Soil With Enough Nutrients
Some people get lucky, and they already have nutrient-rich soil. However, not everyone is so lucky. If you’re part of the latter, you’re not alone.
Many people need to add nutrients to their soil to accommodate their plants. Another good piece of news is that while many plants need a special blend of fertilizer to cater them, olive trees do not.
Most typical, all-purpose garden fertilizers are perfectly fine for olive trees. However, it’s best to use a slow-release fertilizer to even distribute nutrients throughout the season.
Proper Olive Tree Care And Maintenance
If you have your tree set up and ready to go, that’s great! But what do you do after your olive tree is getting plenty of water, sunshine, and all the right nutrients?
You now have to do everything you can to help your olive tree keep thriving!
In this case, we’re not considering providing nutrients, sunlight, and regular watering as part of the ‘maintenance,’ although they are things you absolutely must do.
Right now, we’re going to talk about other ways to maintain your olive tree and keep it healthy to produce for another season.
If Growing Olives Outdoors: A Note On Mulch
If you live in a climate where the weather can get chilly, and you grow your olive trees outdoors, you may need to provide some kind of insulation to the soil near the roots. This is important: don’t use the typical wood mulch.
There are a couple reasons for this: first, the mulch can hold too much moisture. Second, the mulch is so highly carbon-based that it can create a nutrient imbalance. This is particularly true when it comes to nitrogen, although other nutrients are still affected.
What’s the alternative? Pine-based mulching materials are the best option. Pine straw is certainly the top choice, but other pine mulches work as well. USA Pine Straw is a great option, with many devoted customers lauding the quality.
Here’s our guide for making your own pine mulch if you’d like to learn more!
Long-Term Care For Your Olive Tree
Aside from regularly fertilizing and watering, there are other things you can do to keep your olive tree in tip-top shape.
Pruning olive trees is different from pruning other types of trees.
Pruning for olive trees is, unlike so many other fruiting trees, not necessary to get an optimal harvest. However, it can be necessary if you want to improve your tree’s shape, or even encourage it to grow in a way that makes it easier to pick off the wolves by hand.
Not only that, but it can make it easier to avoid damage from branches rubbing against one another, and it can help keep pests from lurking in the branches.
And on that note, another thing you need to keep an eye out for is pests. The good news is unless you live in a subtropical climate, where olive trees naturally grow, you don’t need to worry too much about pests: except for one type. Those are scale insects.
What do scale insects look like? They look like small, dark, circular bumps on your olive tree and typically hide in those ‘V-shaped spots where branches meet and underneath leaves.
If you see these, treat the affected areas immediately, and prune off branches as necessary.
If you’d like more info – take a look at our guide on pruning potted olive trees here!
Most Important Tip For Growing Olive Trees
One of the best tips for growing olive trees is: make sure they get enough water. That’s especially true if you live in an area prone to drought.
The best way to tell if this is an issue for your olive tree is wilting, or curling leaves. While these can be symptoms of other issues, make sure it’s not a drought/excessive heat problem first.
If you want more detail on how this works, the Journal of Experimental Botany published a wonderful study on how extra sunlight during a time of drought can actually have a negative effect on olive trees’ ability to photosynthesize.
That’s A Wrap!
We’ve gone over all the facts, and here’s our conclusion: olive trees need full sun to be healthy.
Here’s why olive trees need full sun:
- Allowing the olive tree to be healthy overall, and be able to feed itself
- Helping the olive tree transition to the reproductive stage (where it produces blossoms and fruit)
- Enabling olives to develop and ripen
- Fueling their growth for harvest (and years of healthy life)
Even if you grow an olive tree indoors, it’s still possible to make sure it gets a healthy level of sunlight. Remember, for olive trees, full sun is more or less equivalent to full health, and if you’re really determined to get many years of good harvests, you need to give your tree the necessities to make it happen.
If you were ever wondering, take a look at what happens after olives are finally grown on a tree!
Agam, N., Cohen, Y., Berni, J. A. J., Alchanatis, V., Kool, D., Dag, A., … & Ben-Gal, A. (2013). An insight to the performance of crop water stress index for olive trees. Agricultural Water Management, 118, 79-86.
Angelopoulos, K., Dichio, B., & Xiloyannis, C. (1996). Inhibition of photosynthesis in olive trees (Olea europaea L.) during water stress and rewatering. Journal of experimental botany, 47(8), 1093-1100.
Gucci, R., Lodolini, E. M., & Rapoport, H. F. (2007). Productivity of olive trees with different water status and crop load. The Journal of Horticultural Science and Biotechnology, 82(4), 648-656. Iniesta, F., Testi, L., Orgaz, F., & Villalobos, F. J. (2009). The effects of regulated and continuous deficit irrigation on the water use, growth and yield of olive trees. European Journal of Agronomy, 30(4), 258-265.
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