Apple tree companion plants are a great way to maximize harvest, make use of space underneath your apple tree, and increase biodiversity in the soil and understory of your apple tree.
What Is An Apple Tree Guild?
An apple tree guild is a group of companion plants planted around the base of your apple tree that benefit the apple tree, and the plants surrounding it.
Companion plants are chosen based on the functions they can perform. Each companion plant performs one or more functions to benefit the apple tree, and the plants surrounding it by interacting with soil micro organisms, insects and animals to create a mini interconnected ecosystem of companion plants that would normally be found growing together, and help each other out by deterring pests, increasing disease resistance and increasing pollination rates.
The benefits of an apple tree guild are to maximize the productivity of the understory, maximize apple yields, reduce our workload, and reduce the amount of imported fertilizers and mulches to create a self-sustaining eco-system.
Apple Tree Companion Plant Functions
Companion plants are meant to provide multiple functions to benefit the apple tree and the other plants in the guild. The main functions we look out for are…
- Suppress Grass and Weeds
- Attract Beneficial Insects
- Repel Damaging Insects
- Provide Biomass for Mulch
- Fertilize the Soil
Some companion plants are great at providing more than one function, so those are the plants we try to incorporate first.
1. Suppress Grass and Weeds
Suppressors are groups of plants whose function is to prevent grass and weeds from growing around the base of the apple tree and competing for important nutrients. Read our guide on apple tree feeder roots and why you should always prevent grass from growing around the base of an apple tree, especially for young apple trees.
Bulbed plants like garlic, onions and leeks, do a great job at repelling grass and weeds. Bulbed plants can be planted in a circle around the tree at the drip line. Their shallow feeder roots will outcompete grasses that try to invade, and by the mid summer heat the bulbs will slow their growth and go dormant and won’t rob the apple tree of its much needed water. Daffodils will also work – but are not edible – and have the added benefit of repelling pests such as deer and gophers.
Vining squashes, rhubarb, mint, creeping thyme, and white clover are also great at shading out the soil and preventing grass and weed seeds from germinating.
White clover is a multi functional plant providing more than one benefit to your apple tree guild by acting as a cover crop to suppress grass and weed seeds from germinating, attracts bees and other beneficial insects, and fixes nitrogen back into the soil.
2. Attract Beneficial Insects
Attractors are plants that attract pollinators and beneficial insects to your apple tree, which means more fruit production from increased pollination rates. A variety of beneficial insects – like predatory wasps – will ensure no single species of insect becomes a pest by controlling its population.
Choose plants that flower before and after your apple tree will. This will ensure the pollinators are not distracted during the apple trees flowering stage. Dill, fennel and coriander are great edible herbs that attract beneficial insects and birds to your apple tree guild.
Insects That Benefit Apple Trees
Lacewings feed on aphids, mites and other small insects and their eggs. Plant dill, angelica, fennel, coriander, queen anne’s lace, and yarrow to attract lacewings.
Lady bugs feed on much the same insects as lacewings, and are attracted to the same plants. Young lady bugs are black with orange markings, and can’t fly, and actually eat more insects than adult lady bugs.
Hoverflies look like tiny honey bees and feed on aphids, mealybugs and other small insects. Some of the plants that hoverflies are attracted to are lavender, mint, lemon balm, parsley, and thyme.
Parasitic wasps are tiny wasps that don’t sting. Instead, they lay their eggs in the bodies of pests such as moths, caterpillars, beetles and flies. As the eggs hatch, they feed off the pest from the inside out. Parasitic wasps are attracted to the same plants as hoverflies, so plant lavender, mint, lemon balm, parsley, and thyme for double duty – to attract parasitic wasps and hoverflies.
Tachinid flies are predators of caterpillars. They lay eggs on the body of the caterpillar. The larvae then suck the fluids from the caterpillar until it dies. Plant buckwheat, tansy and lemon balm to attract tachinid flies to your guild.
Pirate bugs, damsel bugs and big-eyed bugs feed on spider mites, leaf hoppers, aphids, and even small caterpillars. Plant alfalfa, spearmint, fennel and marigolds to attract these bugs.
3. Repel Damaging Insects
Repeller plants are the opposite of attractors, and repel harmful insects and animals. Nasturtiums are normally planted along side apple trees to repel a wide variety of damaging insects. Nasturtiums exude substances that repel pests, but have not been studied extensively.
Plants that Repel Damaging Apple Tree Insects
Chives are great at repelling Japanese beetles that eat your apple tree leaves. It has also been said that chives will help prevent scab when planted among apple trees.
Chrysanthemums planted near apple trees have also been known to repel Japanese beetles that can truly damage and defoliate your apple tree.
Garlic planted near apple trees help repels aphids. It also deters codling moths, Japanese beetles and plum curculio.
Marigolds planted around an apple tree can also repel rabbits – if that is a pest in your area. Rabbits can easily strip the bark off the base of the trunk of a young apple tree, opening it up to a host of other pests and diseases.
Wormwood planted around an apple tree can repel codling moth, which can ruin your harvest of apples as the larvae burrow into the apple to feed off its flesh.
4. Provide Biomass for Mulch
Mulch plants are usually broad leafed / soft leafed plants that have deep-tapping roots that reach deeper than other roots and mine for trace minerals and nutrients. They can be ‘chopped and dropped’ by cutting the leaves at ground level and laying the leaves around the base of the tree to decompose in place while also helping to retain moisture and provide nutrients to the tree and the surrounding plants as it decomposes. Read our guide on how to properly mulch an apple tree for best apple production.
Best Plants to Chop and Drop
Comfrey is one of the most popular ‘chop and drop’ plants for its hardiness and multipurpose-ness. A ring of comfrey plants around the base of the apple tree can be chopped three or four times a summer and left to decompose in place. The leaves from these plants add a huge dose of important minerals and organic matter to the soil to feed the soil life – which in turn suppresses diseases as the soil life competes for food and starves out the diseases. Comfrey also attracts beneficial insects to its flowers, its leaves are medicinal and make great teas – both to drink, and compost tea.
Siberian Pea shrub is also a great plant to chop and drop and has the added benefit of being a nitrogen fixer.
Artichoke, rhubarb, and clover work well also. Their broad leaves grow quickly and provide the biomass required to properly mulch your apple tree.
5. Fertilize the Soil
Accumulator plants increase soil fertility by mining nutrients with their deep taproots. They mine important nutrients like potassium, magnesium, calcium and sulfur. Nitrogen fixers absorb nitrogen from the atmosphere and deposit them back into the soil for other plants to use. Two types of plants that both fertilize the soil.
Accumulator plants cycle nutrients from deep down in the soil and store them in their leaves. Once the leaves are chopped and dropped to decompose in place, those nutrients slowly become available to your apple tree and other shallow rooted plants. After several years, they would have mined all the deep nutrients and will slowly begin to decline. Either pull them out, or move them to another location to begin the nutrient cycle again.
Aside from creating biomass for chop and drop, comfrey, artichoke, and borage are great at mining nutrients deep into the soil and bringing them to the surface for the apple tree and surrounding plants to use once they are chopped and start to decompose. Other accumulators include borage, chicory, dandelions, plantain and yarrow.
Nitrogen Fixing Plants
Nitrogen fixers are plants that absorb nitrogen from the atmosphere and deposit them in the soil in nitrogen nodules, thus improving the soil fertility. Nitrogen is the second largest element required for apple trees to grow (besides water) and is a key element in photosynthesis. Many leguminous plants are nitrogen fixers and have symbiotic relationships with certain soil bacteria to release the nitrogen from the nitrogen nodules, back into the soil.
My favourite nitrogen fixing plants for placing next to an apple tree are sea buckthorn, goumi berry, fave beans and lupine – all of which have the added benefit of being edible. Other nitrogen fixers include white clover – which also acts as a perfect ground cover – peas and alfalfa.
What to Consider When Choosing Apple Tree Companions
The Landscape is important when choosing apple tree companion plants for your guild. Is your apple tree planted on flat terrain, or on a hill? Hilly terrain would benefit from deep-rooting companions like dandelions and comfrey to help stabilize the soil.
Is the soil always wet? Is the planting site in full sun? Think of companion plants that will do well with the landscape you are working with and the climate you are in. Try choosing plants that are native to your area.
Different Layers – Consider the different heights of the plants you are planning on planting. Do you have a diversity of ground covers, herbs, small bushes, vines, and roots?
When planting, make sure to leave enough room to harvest your apples as they ripen by picturing the full sized plants and how they will fit in the guild as they mature.
Plant Arrangement – take some time to figure out where everything will be planted, and try to picture how it will look once everything is fully grown and mature. Leave enough space between plants for them to thrive and mature without competing for space and sunlight.
Place deep rooting plants closest to the apple tree. They won’t compete for nutrients with the shallow feeder roots of the apple tree, but instead will mine nutrients from deep into the soil. Avoid planting plants that will need to be dug up and divided within the drip line of the apple tree. Digging within the drip line could damage the feeder roots once your apple tree becomes more established.
Combinations – try to combine a diversity of plants that will do well in your area, and that will satisfy one or more beneficial functions for the apple tree. Include multiple plants for each function to increase the chances of your apple tree guild working to its maximum effectiveness. Include a variety of food, flowers and herbs.
Choose plants to repel specific pests you may encounter, or attract predators for those pests.
Our Top 10 Cold Hardy Apple Tree Companions
In our climate, our apple tree guild consists of sea buckthorn, dill, borage, chives, artichoke, fave beans, angelica, mint, lemon balm and garlic. Each was carefully selected to perform a certain function for our apple tree.
We have compacted clay soil, so we chose borage and artichoke as our accumulator plants to mine nutrients deep into the soil, and help break up our compacted clay soil. The borage and artichoke both have secondary functions – borage is great at attracting beneficial insects and also works well in salads. Borage flowers are also edible and very sweet, and make a great garnish for a variety of dishes. Artichoke grows quickly and is great at providing biomass for mulch.
Next we chose fave beans and sea buckthorn as our nitrogen fixing plants. Fave beans are very nutritious and can be dried to last through the winter. Sea buckthorn is also a great perennial nitrogen fixing shrub that produces clusters of small orange berries once mature.
Garlic and chives are great at repelling grass and weeds and both help to repel aphids, Japanese beetles and plum curculio – three pests that can wreak havoc on our apple tree. Chives can also prevent scab on apple trees, but our primary focus is on repelling pests.
Angelica and dill are both used to attract beneficial insects. Whenever we can, we try to find perennial shrubs that can perform a function. Angelica is a perennial medicinal herb and along with the dill, will attract lacewings to help with our aphid problem.
Mint and lemon balm are also perennial herbs useful in attracting many beneficial insects to our apple tree guild.
And there you have it, our top 10 apple tree companion plants that you absolutely need in your guild. You can easily adjust your guild to include a few different plants in order to combat certain pests or diseases that are most relevant to your area.