I remember many of my neighbors growing plum trees in their backyard because they are very low-maintenance fruit trees. Now that I’m writing about companion plants, I’m interested in learning which plants grow best near plum trees and some benefits they give one another. Here’s what I found.
The best companion plants for plum trees include comfrey, nasturtium, strawberry, sage, dill, chamomile, and alliums. Ideally, these plants provide benefits such as an increase in pollination, and nitrogen, building healthy soil, and repelling pests and diseases. Avoid planting tomatoes, raspberries, and potatoes.
So, while these are a few great options for companion plants, what are some others, and what exactly do they do to help plum trees? Let’s take a further 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.
Comfrey is a multipurpose companion plant for plum trees. Here are some benefits:
- Comfrey’s leaves are extremely rich in nitrogen, which makes them great for mulching
- Their deep roots pull up nutrients such as calcium, phosphorus, and potassium, helping nearby plants have access to those nutrients as well
- Their leaves are traps for slugs and other pests
- Comfrey’s blue-purple flowers attract pollinators
A variety called Russian comfrey is useful in the garden as its seeds are sterile, making the plant non-invasive.
Comfrey is a sturdy perennial and is hard to remove once it is established, so plan its placement carefully!
Nasturtiums are edible, beautiful, fast-growing, and are great companions for plum trees. Here are their benefits:
- They attract aphids away from the tree.
- The flowers on nasturtiums attract pollinators (usually hummingbirds), which increases the chance these pollinators will also pay a visit to your plum tree’s flowers while they’re in full bloom (ideally within 50 feet)
Nasturtiums come in a wide range of colors, and their sand-dollar-shaped leaves are attention-grabbing. They also have no problem growing in poor soil, as long as it’s well-draining.
You can interplant nasturtiums with any plant on this list for added color and interest next to your plum tree.
3. Alliums (Garlic, Onions, and Chives)
Garlic, onions, and chives (alliums) are companion plants to many. How may they help your plum tree?
- They have natural anti-fungal properties. Since plum trees are vulnerable to fungal infections, planting chives nearby will help support a fungus-free environment.
- They’re also great at repelling certain pests such as aphids, mites, and maggots, as well as rabbits and deer. They’re so effective at this that some deterrents are even made from these plants.
Additionally, their roots are relatively shallow, growing to a depth of 12-18″. This makes them good companion plants since they won’t interfere or compete with the plum tree’s shallow roots.
Chives also bloom in spring and summer with beautiful purple flowers. They’re easy to care for, and have a ton of uses in the kitchen!
Other companions for alliums:
Alliums can grow in zones 3-9, depending on the variety, and need full sun and good drainage.
Strawberries provide plum trees with benefits such as:
- Increased pollination from their flowers
- A perennial ground cover. As a result, more of the tree can be successfully fertilized and the plant’s soil has greatly reduced evaporation from the living ground cover
Also, consider planting strawberry plants with borage under your plum tree.
For example, a recent study showed that borage interplanted with strawberries saw an increase in strawberry production, with 35% more fruits and 32% more yield by weight (source).
Other companions for strawberry plants include asparagus, sage, and thyme. Avoid planting strawberries with mint, cabbage, and melons.
Salvia officinalis, also known as common sage, is a perennial, subshrub with blue to purplish flowers.
Sage is known to be a useful companion plant because of the benefits it provides:
- Attractiveness to pollinators
- Pest-repelling properties
Flowering sage is notably helpful in attracting large numbers of pollinators. For this reason, keep flowering sage plants around your plum tree (ideally within 25 feet and no more than 50 feet away).
It helps repel snails, beetles (such as black flea), and cabbage moths. Many of these pests are also known to eat a large variety of garden plants, especially potatoes.
Not only is sage a great companion plant for plum trees, but also for brassicas such as broccoli, cauliflower, kale, and brussel sprouts, as well as carrots and strawberries. Other herbs that grow well with sage are thyme, rosemary, and oregano.
Avoid planting sage near rue, cucumbers, or onions.
6. Lavender and Rosemary
These two aromatic plants are both amazing companions for almost any plant, especially plum trees.
Here are some benefits:
- Their fragrant purple flowers are highly appealing to beneficial pollinators and insects like bees
- Rosemary usually blooms early, around the same time as plum trees. This blooming timing can greatly benefit the plum tree’s pollination.
- Lavender is also known for repelling ticks, fleas, and many other pests due to its strong oils, and may even drive away mice too.
Both of these plants like hot, dry conditions, which makes them great choices for gardens that experience intense summer heat or in Mediterranean climates such as California and Spain.
For more pest-repelling companion plants, visit my other post: 7 Companion Plants That Repel Pests
Chamomile is a flower known for making tea and having other great benefits for the body and mind. Here are some benefits it provides plum trees:
- Fixes nitrogen in the soil
- Attracts beneficial insects
- Grows well in partial shade
- Easy to grow
You can plant chamomile underneath or near the plum tree. For best results, plant on the east side of the tree to allow for partial shade during the hot afternoon sun.
There are two main types of chamomile: German (Maricaria recutita) and Roman (Anthemis nobilis). Both are beneficial to have as companion plants.
First, chamomile brings up nutrients from deeper into the soil. Their flowers also attract beneficial insects such as hoverflies, ladybugs, beneficial wasps, and honey bees.
If you weren’t aware, many of these helpful bugs are predatory to pests. For example, ladybugs are a natural predator of aphids and will help keep their populations down.
Chamomile also grows well with mint and basil.
Wildflowers are defined as any flower that has not been genetically manipulated.
- Bee Balm
- Queen Anne’s Lace
- Purple Coneflower
- Meadow Cranesbill
- Black-Eyed Susan
Wildflowers are an amazing companion plant for plum trees as they attract a variety of beneficial insects, such as pollinators.
More specifically, the wildflower’s variety of colors is visually appealing to pollinators and provides a good mix of nectar they can use as energy.
An increase in pollination for plum trees means more fruiting, bigger fruits, and fewer fruit drops.
You can plant a single wildflower variety or interplant a mix to have a wide range of colorful flowers in your garden.
To see more companion flowers, check out my other post: The Top 10 Companion Flowers for Gardens, Vegetables, & More.
9. Cover Crops
Many legumes (along with some grasses such as annual ryegrass) are called cover crops as they are fantastic pioneer plants to restore depleted soils ahead of plum trees.
Some examples of cover crops are:
- Other beans
- Annual Ryegrass
- Cereal Grasses
Here are the primary benefits of cover crops:
- Fixes nitrogen in the soil
- Slows erosion
- Retains water
- Preventing weeds
- Controls pests and diseases
Since fruit trees are heavy feeders of nitrogen (their primary nutrient), nitrogen fixers like cover crops are incredibly useful.
For example, in the drought of 2012, corn and soybean farmers reported a 9.6-11.6% yield increase when they used cover crops, likely due in part to the cover crop’s ability to add 50-150 pounds of nitrogen per acre.Sustainable Agriculture Research and Education
To maximize the nitrogen and nutrients for other plants, cover crops should be mowed or chopped and dropped as mulch before they seed.
You can even grow some cover crops such as clover in-between your fruit trees. Livestock can then be run through the alleys to eat the cover crops and contribute fertilizer as manure.
If you’d like to learn more about cover crops, check out this resource by Sustainable Agriculture Research and Education (SARE).
Like sage, dill is another drought-tolerant herb native to the Mediterranean, and is part of the parsley and celery family.
One of the most well-known companion qualities of dill is its ability to attract pollinators and beneficial insects such as ladybugs.
So, if your brassicas commonly get aphids, plant lots of dill!
You can also use dill in your garden to repel pests such as spider mites and cabbage loopers (source).
Plant dill with brassicas, lettuce, onions, corn, cucumbers, and fennel. However, avoid planting dill with carrots, caraway, and nightshade.
To see more companion herbs, check out my other post: The 10 Best Companion Herbs.
What To Avoid Planting Near Plum Trees
Avoid planting raspberries due to their vigorous growth. They can not only compete with the peach tree’s nutrients but also hinder the tree’s root growth.
Additionally, nightshades, such as tomatoes, potatoes, and peppers, have been known to introduce disease to plum trees.
Deep-rooted plants such as potatoes, carrots, and other tubers or root vegetables can interfere with and even damage some of the fruit tree’s shallow roots, especially if they’re planted near or under the fruit tree’s canopy.
Also, some nut trees such as walnut produce a chemical called juglone, which inhibits the growth of other, nearby plants.
Where Do You Plant Plum Tree Companion Plants?
For companion plants that need more sun, such as strawberries, wildflowers, lavender, and rosemary, consider planting them outside of the tree’s canopy.
Others such as clover, nasturtium, dill, chamomile, and chives like partial sun and can be planted underneath the plum tree.
As mentioned above, companion plants can be planted just about anywhere, as long as they don’t damage the tree’s shallow roots and are within 50 feet of the tree to maximize pollination results.