Growing olive trees can be a rewarding experience, but getting the most out of them often means looking beyond just the tree itself. I’ve spent years experimenting with what works well planted around and under my olive trees, and I’ve learned a few things the hard way. It’s not just about aesthetics; the right companion plants can make a real difference in the tree’s health and even its fruit production.
For a long time, I just planted whatever looked pretty near my olive trees, assuming they’d all get along. What I found was that some plants just didn’t thrive, and others actually seemed to compete too much. The key, I realized, is understanding the olive tree’s needs and then finding plants that complement those needs, rather than fight against them. It’s a bit like building a small, self-sustaining community in your garden.
Why Companion Planting Matters for Olive Trees
When you think about companion planting, it’s easy to focus on the obvious benefits like pest control or attracting pollinators. And those are definitely big parts of it. I noticed a significant drop in aphid issues on my citrus trees when I started underplanting with flowers that attracted ladybirds. The same principle applies to olives.
Beyond that, companion planting can help with soil health, moisture retention, and even nutrient cycling. It’s about creating a microclimate that benefits the main crop. For olive trees, which often prefer well-drained soil and plenty of sun, choosing the right companions can prevent issues before they start.
Mediterranean Herbs: A Natural Fit
If there’s one group of plants that consistently performs well around olive trees, it’s Mediterranean herbs. This isn’t surprising, given their shared origins. They generally love the same conditions: full sun, light, free-draining soil, and not too much water once established.
Lavender
Lavender is probably the most popular choice, and for good reason. The aroma is lovely, and the purple flowers are beautiful. I’ve found that it definitely helps with pollination, bringing in more bees to the area, which is great for any flowering plant, including olives. It also seems to deter some common pests, though I wouldn’t call it a foolproof solution. Just a helpful addition.
However, I made the mistake of planting lavender directly into heavy clay soil under an olive tree once. It didn’t do well. I learned that for Mediterranean plants in clay, digging in a good 50% grit around the base of the olive tree really helps improve drainage. Without that, lavender can struggle.
Rosemary, Oregano, and Thyme
These three are also excellent choices. They’re tough, drought-hardy once established, and their scents can confuse pests, making it harder for them to find your olive tree. I particularly like planting lower-growing oregano varieties like ‘Herrenhausen’ or ‘Rosenkuppel’ directly under the tree. They act as a living mulch, helping to suppress weeds and keep the soil a bit cooler, while still allowing the olive tree’s roots to breathe.
Rosemary also makes a fantastic, architectural planting around olives, with its upright growth and fragrant needles. Thyme, with its low-growing, spreading habit, is another good option for ground cover that smells great when brushed against.
Attracting Beneficial Insects
One of the most effective ways companion planting helps is by inviting the good guys into your garden. These are the predatory insects that feast on the pests that might otherwise bother your olive tree. Aphids, for example, can be a nuisance on new growth.
Dill and Fennel
I’ve seen firsthand how planting dill and fennel nearby can increase the presence of beneficial insects. These plants are magnets for ladybirds and lacewings, which are voracious eaters of aphids. It’s a much more natural and sustainable way to manage pests than reaching for sprays. Just be mindful that fennel can get quite tall, so plan its placement accordingly to avoid shading out smaller companions.
Nasturtiums
While not strictly Mediterranean, nasturtiums are fantastic for attracting pollinators and can also act as a ‘trap crop’ for aphids. I’ve found that aphids often prefer nasturtiums to other plants, drawing them away from more vulnerable crops. Plus, their vibrant flowers add a cheerful splash of color, and the leaves and flowers are edible, which is a nice bonus.
Ornamental and Architectural Companions
Sometimes, companion planting is also about creating a harmonious visual landscape. Olive trees have a distinct, elegant look, and certain ornamental plants can enhance that aesthetic while still being good companions.
Petunias
I was initially skeptical about petunias, thinking they were just for annual color, but I’ve found them surprisingly effective. Planting petunias directly around olive trees can help ward off certain harmful insects. They’re also relatively low-maintenance and provide continuous color through the warmer months, making the area under the olive tree look more intentional.
Mediterranean Grasses and Succulents
For a more architectural feel, I’ve had good luck with plants like Festuca glauca ‘Elijah Blue’. This dwarf ornamental grass offers an intense blue color that contrasts beautifully with the silvery-green of olive leaves. It’s drought-resistant and adds texture without competing too much.
Yucca Rostrata and Dasylirion Longissimum are also excellent choices for a modern, low-maintenance look. They are slow-growing, drought-resistant evergreens that add a stylish, architectural edge. Palm trees, surprisingly, can also be good companions, offering a different kind of architectural interest and adapting well to hot summers and cold winters, much like olives.
Considering Soil and Water Needs
This is where I’ve made the most mistakes in the past. Olive trees, like many Mediterranean plants, prefer well-drained, even somewhat poor soil. They don’t like to have ‘wet feet.’ When choosing companion plants, matching these needs is crucial. Planting moisture-loving plants right next to an olive tree will either stress the olive or kill the companion.
Always consider the mature size of both the olive tree and its companions. A small plant might look fine now, but if it grows into a thirsty giant, it will compete with the olive tree for resources. I always try to pick plants that are known for their drought tolerance once established. This simplifies watering and ensures everything thrives with minimal intervention.
My Approach to Companion Planting
What I’ve settled on is a layered approach. I start with the core Mediterranean herbs like lavender, rosemary, and oregano directly under or very close to the olive tree. These provide the most direct benefits in terms of pest deterrence and attracting pollinators, and their care needs align perfectly.
Further out, I’ll incorporate some of the beneficial insect attractors like dill or fennel, making sure they have enough space. And then, for visual interest and to fill in gaps, I might add some ornamental grasses or even petunias. The goal is a cohesive, low-maintenance planting scheme that supports the olive tree while looking good.
It’s a continuous learning process, and every garden is different. But by focusing on plants with similar needs and understanding the benefits each companion can offer, you can create a thriving environment for your olive trees. It’s about working with nature, not against it, and finding those plants that genuinely seem to enjoy each other’s company.
