Companion Plants–Benefits In The Garden

Companion plants are a tradition that has been followed throughout time.  The benefits are tried and tested so that many books have been written on the subject of companion plants. Finding good plants to pair together is fairly easy.  But, why do some plants work with others, and what are those benefits?
Companion plants are grouped together for several reasons. 
1)  One plant can repel insects that typically attack the other plant.

Some scented herbs are repulsive to some insects that may want to devour other plants in the neighborhood. Mint, for instance, will repel ants and aphids.  Fennel repels fleas and is known by the cute, but appropriate rhyme ‘plants fennel around the kennel’. Other aromatic plants that are unattractive by pests are scented geraniums, camphor, lavender, rosemary, and sage.  Inter-plant these in the garden to drive pests away.

A natural insect repellent made from Chrysanthemums is call pyrethrums. When planted as companion plants, chrysanthemums repel insects such as aphids, ticks, bedbugs, spiders and certain insect pests on broccoli.

Basil planted with tomatoes will repel the tomato hornworm. And these two plants make a great combination at dinner time for the family.

2)  Some companion plants can improve the soil for the other.

Legumes are an example of nitrogen-fixing plants.  Legumes can extract nitrogen from the air, and bring this essential element down into the root zone for their neighbors benefit.  Vetches and clovers also have this ability of nitrogen-fixing, and when used as a cover crop, they not only draw down nitrogen, but when they are plowed under, they provide organic material to the soil.

3)  Some plants have similar growing needs and do well together.

Many plants have similar growing requirements.  Some need full sun, some need shade.  Some plants like moist soil, while others do not.  Familiarizing yourself with the growing needs of plants and placing together those that like the same conditions is good companion planting.  Plants that need full sun and little supplementary water make good bedfellows.  Similarly, plants that require moist soils, will be together and make watering more efficient.

Study plant tags or ask the staff at a garden center which plants need a similar environment.

4)  Some companions just look good together.

Textures, colors, and forms of plants that play off of each other make good companion plants.  Colors that match make a good color garden – i.e. a white garden. Colors that are opposite on the color wheel contrast and are pleasing to the eye. Yellow opposite purple, or blue opposite orange, make good aesthetic combinations for companion plants.

5)  Some plants improve the health of it’s neighbor.

Herbs make great neighbors in the garden.  Their aroma is a sensory compliment to roses, and  Marigolds planted around the garden may even encourage growth.
Insectary plants are used to draw beneficial insects to the garden. The pollinators are attracted to plants that have little flower heads, and many florets. These composite flowers of asters, marigolds, zinnias, and lettuces have many parts for the insect to draw nectar called inflorescences.

Trap plants are those that draw insects and are sacrificed to the pests.  Some trap plants are nasturtiums and Chinese cabbage.When the insects are feasting on the nasturtium, they leave the crop plant alone.

Garlic is said to help prevent leaf curl in peach trees, and stop scab in apple trees.  Garlic near tomatoes may repel red spider mites. 


Beneficial habitats, or refugia, are companion plantings that provide good growing environments for plants.  Good insects, including pollinators and parasitic insects, keep pests under control.

Here, nurse crops, help protect others.  the tall plants can help shade plants that may suffer in too much sun or heat. 
Cucumbers are shading lettuce.  Sunflowers can cast shadows on shorter plants - both nurse croppings and good companions plantings. 

 The seed catalogs are out and nurseries are getting their seeds into the stores, so it is planning time for this year’s garden. This is a great time to pair plants that make good companions in the garden.

What companion plants do you rely on?  Which ones disappointed you?  Share your comments, so we all can benefit.  Thanks for stopping by today.