20 Companion Plants You Can Grow To Encourage A Healthier Plum Tree

As a gardener, few things are as rewarding as enjoying the (literal) fruits of your labors. However, even if you start from a sapling rather than growing your orchard from seed, seeing successful fruit requires time, effort, and plenty of patience. Fortunately, as you learn how to grow plum trees, there are ways to boost your plant's chances at success in your garden — and it begins with companion planting.

Companion plants are those that you can grow together for different benefits. When you add a variety of companion plants to your garden for the purpose of supporting one plant in particular, such as your plum tree, this is then known as a guild. Companion plants can serve a range of purposes when it comes to helping encourage a healthier plum tree. Choosing the right plants, like borage, marigold, and chives, for your local climate can be a great place to start when you're hoping to see more fruit.

While some plums have the ability to pollinate themselves, others rely on cross-pollination for bushels of delicious fruit. As a result, along with keeping factors like pest control, water retention, and nutrients in mind, you'll also want to consider pollinator-attractors when picking the best companion plants for plum trees.

When it comes to companions, dill (Anethum graveolens) is a popular choice for many plants, including fruit trees like plums. Dill blooms with clusters of yellow flowers, which not only elevate your garden's visual appeal but also attract helpful pollinators like butterflies. This plum tree companion plant offers other benefits too, such as attracting ladybugs and predatory insects, which can help control harmful pests. Dill grows best in areas with full sun or partial shade.

Lavender (Lavandula angustifolia) is another top contender for beneficial companion plants. Plum trees aside, lavender showcases fragrant purple flowers that both you and pollinators can enjoy. You can grow lavender in zones 5 through 9 in full sun or partial shade, and its overall hardiness makes it a low-maintenance plant. If you're looking for bigger, more abundant blooms, there are also ways to encourage your lavender plants to produce more flowers. 

Scarlet bee balm (Monarda didyma) is a native flower in North America that thrives in zones 4 through 9. It's a keystone in many ecosystems, attracting a variety of pollinators while also providing shelter for several larval species. Bee balm can even provide a rest spot for certain bees. While this contributes to your garden's overall biodiversity, it can also help your plum tree by providing the pollinators it needs to survive. Bee balm also has a strong fragrance that may be able to deter pests, while the taste of its leaves often keeps deer from nibbling.

You may be familiar with chamomile (Matricaria spp.) as a tea, but it can also be a useful part of your plum tree's guild. There are two types of chamomile, German and Roman, and both can be used to help encourage pollinators to visit your garden while also attracting the natural predators of any harmful insects that may damage your tree or ripening fruit. You can grow this annual in zones 2 through 8, and it does well in partial shade and in sunlight.

Providing enough nutrients is important for any plant's success, and plum trees are no exception. That's why, while focusing on pest deterrent and pollinator attraction is important, you'll also want to consider companion plants that can give back to the soil when choosing your guild. Borage (Borago officinalis) offers stunning flowers with nectar that beneficial insects love. However, once their blooms are gone, you can cut down, chop up, and leave your borage plants to decompose naturally to create beneficial mulch for your plum tree. This helps cycle nutrients for healthier soil. 

Rosemary (Rosmarinus officinalis) is another companion herb you may want to consider when picking out the right plants for your plum tree. While you may need to consider planting them further away from your tree for the right amount of sunlight, they share a similar blooming season with plums. This means more flowers to capture the eyes of pollinators. With its strong fragrance, it may also be helpful at discouraging pests from paying your garden a visit. While easy to grow, rosemary does best in zones 8 through 10.

Related to borage, comfrey (Symphytum officinale) offers many of the same benefits. Its bell-shaped flowers are a fan-favorite among the pollinators that your plum trees need, and it can act as homemade mulch in your garden when cut and composted, just like borage. This plant grows best in zones 3 through 9, and its need for similar conditions allows it to be grown alongside borage in many environments.

Japanese beetles can pose a significant threat to many fruit trees, including plum trees. For well-established trees, their leaf damage may only be cosmetic. However, for younger trees, they can be a greater problem. Some studies, such as a 2003 Environmental Entomology study, have shown that ingesting certain geraniums, like zonal geraniums (Pelargonium × hortorum), can cause temporary paralysis in Japanese beetles. This leaves the beetles exposed to predators. It's important to note that these geraniums are not the same as those in the genus Geranium, which shares the same common name.

Part of the lily family, chives (Allium schoenoprasum) produce purple flowers that add a splash of color to your garden. Depending on the variety, you can enjoy chives in zones 3 to 9. Along with their eye-catching flowers, chives can help maximize the garden space around your plum tree thanks to their use in the kitchen. If you're working with a small outdoor space, choosing plants with various purposes can help make the most of your soil. Chives can be a good choice for potentially deterring pests, and they also sport anti-fungal properties.

Daffodils (Narcissus spp.) offer variety, with many options to choose from. As a result, it's important to pick the right daffodil for your garden. This involves paying attention to your selection's hardiness zones, which can range from 3 to 8, as well as any differences in light and water requirements. While you may know daffodils from their fun appearance, they can be a useful part of your fruit tree's guild due to their ability to deter pests. And, like other flowering plants on this list, their colorful blooms can help also attract pollinators. 

Marigolds (Tagetes spp.) can be a helpful addition to your plum tree's guild. They sport round, bright blooms that make them a favorite among gardeners and pollinators alike. However, they also have long blooming seasons, which means more time to reap their benefits. While some deer may still steal a quick bite from marigolds, these companion flowers can act as a deterrent for deer and rabbits.

Nasturtiums (Tropaeolum spp.) are more orange-yellow flowering plants to consider adding to your guild. They grow in the same conditions as marigolds and offer resistance to curious deer. They're also edible, helping maximize space in your garden much like chives. As a companion flower in your guild, nasturtium offers many benefits, from deterring pests to providing ground coverage for healthy soil to luring in pollinators.

One thing to keep an eye out for when picking companion plants are plants that are easy to grow. Thankfully, cilantro (Coriandrum sativum) offers easy growing without sacrificing benefits like pest management and attracting pollinators. You can also use this annual herb in cooking, helping it pull double duty in your garden. Cilantro does well in a container, and is a low-maintenance plant that can grow in partial shade or full sun. Just make sure to brush up on your knowledge of companion herbs to ensure cilantro is compatible with other herbs you may have chosen for your guild. 

Wildflowers are an essential part of your local ecosystem. By choosing plants native to your area, you can attract the wildlife that depend on them, helping create a balanced environment in your backyard. As a result, black-eyed Susans (Rudbeckia hirta) to your plum tree's guild can help you see an uptick in pollinators. And, when you choose wildflowers native to your area, it can reduce the workload that goes into maintaining those plants, creating a beginner-friendly garden. As far as USDA zones go, aim for zones 4 through 10 for optimal growth.

Another herb to make its way on this list, oregano (Origanum spp.) is a culinary staple that comes in a variety of forms. It can hold up well to foot traffic, which is an important feature to consider when planting ground coverage. Like other fragrant companion plants, such as chive, it can also help deter pests from turning your plum tree into a buffet. Because there are different species, your choice of oregano may have different needs. As a general overview, however, this plant grows in full sun in zones 3 through 10 in the United States.

Clover (Trifolium repens) is one example of a cover crop, and it can serve an important function in encouraging a healthier plum tree. Cover crops can reduce erosion and retain water while also helping add nitrogen to the soil. However, to take advantage of these benefits, as it's important to cut and mulch your clover, and other cover crops, before they seed. Alongside these benefits, clovers are essential for some butterfly species. If this sounds like the right fit for your guild, clover can handle full sun or partial shade in zones 3 through 10.

Yarrow (Achillea millefolium) comes back year after year, which is helpful in maintaining a long-lasting fruit tree. This hardy plant thrives in an assortment of conditions, although it does best in zones 3 through 9 in full sun. Like many of the other flowering herbs on this list, yarrow provides two main benefits: Flowers that attract pollinators that plum trees need and a fragrance that helps deter harmful insects.

As shown with other edible plants on this list, part of choosing the right companion plants involves maximizing space. One good way to do this is by incorporating other fruit-producing plants around your plum tree. Strawberries (Fragaria spp.) provide ground coverage that returns each year, and they can also grow alongside other popular companion plants, like borage. Plus, with their flowers, they can be a hit among pollinators. Specific needs depend on the exact cultivar of strawberries you choose. However, overall, plan for these to thrive in zones ranging from 3 to 9.

Purple coneflowers (Echinacea purpurea) are another perennial wildflower that can help support your plum tree. They grow eye-catching purple flowers with long blooming seasons, which can aid in attracting pollinators for your plum trees. Butterflies and bees aren't the only insects that are drawn to these blooms, however. Like many other native flowers, purple coneflowers can also attract ladybugs and other predatory insects that feed on pests in your garden. Birds also enjoy their seeds. To grow purple coneflowers, aim for partial shade or full sun, with well-draining soil. They also grow in zones 3 through 8.

Garlic chives (Allium tuberosum) are similar to chives but not the same, with white flowers that bloom later in the season in zones 3 through 9. Although their eye-catching appearance is one reason to include them in your garden, when it comes to acting as a companion plant for plum trees, garlic chives can help repel pests. This keeps your tree and its fruit healthier for your enjoyment. These flowering herbs can also spread, creating move coverage for the soil around your tree. Just keep in mind that this spread also means garlic chives can grow aggressively in some conditions.