We have an orange tree in our backyard and while it has a good amount of oranges, we wanted to see if companion plants could help it fruit more. So, I did some research to find out. Here’s what I found.
The best companion plants for orange trees are nasturtium, comfrey, alliums, wildflowers, and jasmine. Ideally, select orange tree companions that share a similar climate and fill different niches. For example, jasmine and nasturtium are ground covers that also attract many pollinators—helping the orange tree fruit.
So while orange trees have many companions, exactly what benefits do they bring, and what are some other companions? Let’s take a closer look.
Companion Planting Pro Tips (Before You Start)
Companion planting is selecting specific plants to place together for benefits such as increasing pollination or controlling pests. Sometimes these benefits are one-sided, while others are mutual.
A famous example is The Three Sisters—planting corn, beans, and squash together. The corn provides a trellis for the beans to climb, the squash provides a ground cover, and the beans fix nitrogen in the soil. Plus, all of them provide food!
Here’s how to get the most from companion planting:
- Find your USDA hardiness zone
- Select plants that do well in your zone
- Choose the plants that fit each niche or layer in the graphic above (canopy, understory, herb layer, etc.)
- Plant support species first to establish a microclimate and build the soil. For example, before planting fruit trees, grow nitrogen-fixing trees, shrubs, and flowers. Plant one nitrogen fixer for each productive plant (such as fruit trees or berry bushes).
Now, let’s take a look at the best companion plants, their benefits, and other tips to place them in your garden.
1. Nasturtium
Most people I know have never heard of nasturtium, but when I show them a picture they quickly recognize it.
Nasturtium is often believed to be a weed, likely because it grows quickly and horizontally along the ground. However, this is what makes nasturtium such a great ground cover—which dramatically helps orange trees by reducing evaporation, regulating soil temperature, and preventing soil erosion.
Another reason why it’s great as an orange tree companion plant is because it attracts pollinators and its edible flowers have nectar that’s sweeter than most others. This is since it’s made from highly concentrated sucrose instead of glucose or fructose. As a result, it’s a highly desirable plant for pollinators.
Fun fact: nasturtium’s long flowers evolved alongside the hummingbird’s long tongue (source).
Aside from providing ground cover and pollination, nasturtium has another benefit in companion planting—it attracts pests such as aphids and cabbage worms away from other plants (source). In this way, you can think of nasturtium as a “trap” or “sacrifice” plant. It’s also pretty durable when it comes to pests, so you shouldn’t have to worry about nasturtium becoming damaged.
However, if your nasturtium starts to get overrun with pests, plant dill, calendula, and cosmos nearby to help deter them. For more info about these companion plants and others that repel plant pests and diseases, check out my other post: 10+ Companion Plants That Prevent Pests and Diseases.
Plant nasturtiums along with orange trees (and other fruiting plants), legumes, tomatoes, asparagus, and brassicas. Of course, nasturtium has many other companion plants.
Avoid planting nasturtiums with squash and other vining plants since they can easily get tangled and compete. However, nasturtium’s shallow roots also mean that it’s not difficult to remove if you decide to part ways with it.
So, if you’d like a ground cover that attracts many pollinators (especially hummingbirds), plant nasturtium!
2. Comfrey
Comfrey is one of the most popular companion flowers at the moment because not only can it be used to attract pollinators but it grows incredibly fast and tall—eventually falling over and making a great mulch for other plants.
This mulch then reduces evaporation, provides protection from the elements, and adds nutrients to the soil.
Comfrey also fixes nitrogen in the soil, meaning its roots attract beneficial bacteria which take nitrogen from the air and store it as nitrates in the soil, ready for plants to use (source). As orange trees are heavy feeders of nitrogen (their primary nutrient), nitrogen fixers like comfrey are incredibly useful.
As a result of its nitrogen-fixing properties, comfrey is a great choice to use for growing in and improving poor soils.
In his book, Peter Wohlleben Professional German forester, The Hidden Life of Trees, calls these nitrogen-fixing plants pioneer plants. Pioneer plants pave the way for more sensitive plants, such as orange trees. This process of support species leading to more productive ones is called ecological succession.
Comfrey grows best in USDA hardiness zones 3-9, but it will grow pretty much anywhere. It also prefers a soil pH of 6.0-7.0 (which is the same as orange trees!).
For best results, plant comfrey next to orange trees, as well as vegetables like asparagus. However, comfrey grows well with just about every plant.
Keep in mind that while comfrey doesn’t have any foes, it can grow and spread aggressively. Because of this, many gardeners prefer to grow Russian comfrey due to its sterile seeds.
So, if you need more pollination, mulch, or nitrogen in your garden, grow comfrey!
3. Alliums
Alliums are incredibly important companions for orange trees as they repel many pests such as aphids, mites, maggots, rabbits, and deer (source).
Additionally, it’s believed that the sulfur from these plants also helps prevent certain plant diseases to some extent. For example, a common companion plant pairing is interplanting chives near apple trees to prevent apple scab (source).
However, if fungal or bacterial diseases do take hold, garlic cloves can also be mixed into organic sprays along with neem oil and applied as a treatment.
Overall, you can interplant any of these allium-family plants with just about any other plant, except for legumes.
4. Wildflowers
So, what exactly are wildflowers?
Wildflowers are defined as any flower that has not been genetically manipulated (source).
They include:
- Daisies
- Poppies
- Bee Balm
- Queen Anne’s Lace
- Purple Coneflower
- Meadow Cranesbill
- Lupine
- Black-Eyed Susan
Wildflowers are an amazing addition to your garden, especially if they’re within range of your orange trees. Ideally, this is around 25 feet or closer, but no more than 50 feet away as it maximizes the chances pollinators will visit both the wildflowers as well as your orange tree’s flowers.
And even self-pollinating fruit trees benefit from cross-pollination.
All varieties of apple trees require some cross-pollination for fruit set. Even though some varieties are listed as self-fruitful, they will set fruit more heavily and more regularly if they are cross-pollinated.
Washington State University
These varieties of wildflowers are especially appealing to pollinators and provide a good mix of nectar and pollen they can use as sugar and protein.
Wildflowers also attract beneficial insect predators such as birds, ladybugs, and beneficial wasps, which naturally keep pest populations down.
Any of the above wildflowers will work great as a companion plant for just about any fruit, vegetable, or herb plant. However, this isn’t an exhaustive list, so feel free to explore other wildflower varieties!
To see more companion flowers, check out my other post: The Top 10 Companion Flowers for Gardens, Vegetables, & More.
5. Jasmine
Speaking of jasmine, this hardy subtropical plant can grow in USDA zones 7-10, but it’s ideal to use in tropical and subtropical climates (zones 9-11, source). Because of this, it’s great to pair with tropical plants, which of course includes orange trees!
Jasmine’s two biggest benefits are providing a ground cover and pollinator attractor.
Generally, jasmine is a choice companion plant to use in the vining and ground cover niches. It helps tie in other companions such as overstory, midstory (like orange trees), and understory plants—filling in the gaps of sunlight left by these plants’ canopies.
Its vining nature allows it to spread horizontally along the ground, reducing evaporation and regulating soil temperature. On the other hand, its strong-scented flowers attract tons of pollinators and beneficial insects including butterflies, hummingbirds, bees, and ladybugs.
Keep in mind that jasmine grows vigorously, so it can compete with other ground covers or vining plants.
Some companion plants for jasmine are clematis, bamboo, hibiscus, and mango trees.
6. Lavender, Rosemary, and Sage
Rosemary and lavender are natively from the Mediterranean while sage is from the southwest US (source), which makes them all good drought-tolerant plants.
Each of these plants attract pollinators and repel pests such as slugs and snails through their high-resin flowers and leaves (source). And planting them together compounds these effects.
Since rosemary, lavender, and sage can grow into fairly tall bushes, it’s best to plant them a few feet away from your orange trees. As long as you plant them within 25 feet of your orange trees, you’ll get most, if not all of their benefits.
You can also take cuttings of these herbs, bundle them, tie them with twine, and hang them upside down to dry them out and store them for later. All three of these herbs also compliment oranges!
Some other plants that also pair well with these companion herbs include thyme and oregano. However, avoid planting sage near rue, cucumbers, or onions as they’re not compatible.
7. Avocado Trees
Like orange trees, avocado trees are tropical fruiting trees and go great when planted together. They attract pollinators like crazy and provide other companions such as understory and ground cover plants with partial shade, water retention, mulch, and more.
While avocado trees are great once you get them going, they are notoriously more sensitive than the other plants on this list. They commonly get issues such as leaves drooping, yellowing, or browning.
But, once they mature, and are in well-draining soil, they’ll grow and fruit nicely.
Keep in mind that even though avocado trees are technically self-pollinating, they do require another avocado tree of a different type (type A or B). If you’d like to see more about the different avocado types, you can check out my recent post on why avocado trees won’t flower or fruit.
Some other avocado tree companions are lavender, melons, and sweet potatoes.
8. Mexican Sunflower
Mexican sunflowers (Tithonia diversifolia) attract tons of pollinators and grow best in USDA hardiness zones 9 and above, so they’re great to plant with your orange trees. This flowering plant grows to a height of 4-6 feet.
I first heard of Mexican sunflowers from Pete Kanaris at Green Dreams Farm. He claimed that, when mulched, it the same amount of nitrogen pound for pound as chicken manure. Because of this, they’re often called green manure. And based on his backyard food forest’s growth, I’d say that it’s clearly working!
To see Mexican sunflower mulch in action, check out this video by Pete.
9. Birds of Paradise
Birds of paradise are another great understory plant. This flowering plant can grow to a large width, providing a boost to pollination soil shading—making it a good companion plant for orange trees. In fact, birds of paradise are one of the companion plants we choose to use for our orange tree.
Like many of the other plants on this list, birds of paradise are fairly flexible with their soil pH, requiring a range between 5.5-7.5.
These plants commonly have a root ball that is about 1-2 feet wide, so make sure to allow enough space from other plants. Good spacing is about 4-6 feet from other plants, but a well-managed garden or food forest can allow for more density (source).
However, when planting birds of paradise in the understory of other plants, make sure to allow for enough sunlight to reach them, as they require full sun (6+ hours a day). As a result, planting them just outside of the orange tree’s canopy works best.
10. Sweet Potatoes
Similar to vetch, sweet potatoes are an amazing perennial ground cover (annual in temperate climates) and provide much-needed water retention, soil temperature regulation, and reduced soil erosion.
Since sweet potatoes are not related to regular potatoes (part of the nightshade family), their leaves are actually edible.
Sweet potatoes are also easily propagated as you just need a single stem or slip (either from the tuber or vine). As long as you have decent, loose soil, and moderate watering, you’ll have tons of sweet potatoes ready to harvest in a single season.
Keep in mind sweet potatoes can compete with other vining plants or ground covers if they’re both near each other and grown in the same niche. For this reason, consider growing sweet potatoes as a ground cover and other vines on a vertical trellis.
What Not to Plant with Orange Trees
Avoid interplanting orange trees with plants that have deep roots such as potatoes and carrots. These plants can interfere and compete with the orange tree’s shallow roots. Sweet potatoes can also compete with orange trees, but growing sweet potatoes outside of the tree’s canopy avoids most if not all of the orange tree’s roots.
