There's no clear winner in such an argument, as organic gardeners will point to their lush, vibrant gardens as proof that companion planting achieves results.

Skeptics will undoubtedly remain unconvinced and continue to hold to their claims that it's impossible to say for sure without controlled testing. Plus, they can also point to many examples of healthy gardens where companion planting played no part in the design.

If you've yet to use plant pairing in your garden or you are already convinced of the benefits of companion planting, the truth is, you won't do any harm to your plants by incorporating companion planting design principles into your garden layout. There are also a ton of great reasons why you should try it out.  

Centuries of modern agriculture have taken their toll on viable cropland, and more scientists are becoming interested in studying how plant pairing can improve crop yields, increase diversity, and promote plant growth.  

The good news is, plant pairing is not complicated, so nothing is stopping you from doing your own testing. Use two different layouts, one with companion planting and another without, and compare your results. Experimentation is a fantastic way to learn new gardening techniques and discover what will and won't work in your area. Here's how to get started with companion planting and pairing vegetables in Arizona.

How Does Companion Planting Work?

The most important part of the garden design philosophy in companion planting is diversity. Growing the same species together in a section of the garden means that young plants compete for the same resources, which can be detrimental to optimal health.

Pests that prefer certain species will also have a readily available source of nutrients within easy reach of each other. If insects manage to infest one plant, then they can quickly spread to the other plants in the group. Separating different garden varieties more closely resembles the balanced ecosystem of mother nature.

Insects and other pests locate their food using sight and smell, and a diverse layout of different varieties of plants will help confuse them. A hungry creature will choose the path of least resistance, so the more difficult you make it for them to find a suitable source of nourishment, the more likely they are to try their luck elsewhere.

Confusing the pests by breaking up the plants is one way to prevent an infestation, but you can also use other plants that exude oils and strong odor to mask the scent of their favorite food growing nearby. In this way, the companion plant hides the target plant in plain sight. Plants like marigold, garlic, lavender, sage, and rosemary are all excellent masking varieties you can use to hide the scents of the plants you wish to protect.

Another companion planting strategy is called trap planting. In this companion planting technique, a less valuable plant is grown nearby, and the sacrificial plants serve their purpose by luring the insects away from the main crop.

The Benefits of Companion Planting and Pairing Vegetables

Designing your garden around carefully paired vegetables can help you reduce your level of maintenance, as well as your reliance on artificial and sometimes toxic pest control techniques. Here's how pairing vegetables in Arizona will provide a more bountiful harvest.

Controlling Insect Populations

Unfortunately, many of the insects in your garden depend on a ready supply of vegetables for their survival just as much as humans. It's a battle that humans have been fighting for centuries, and there's no end in sight.

Rather than try to achieve complete eradication with chemicals, companion planting uses mother nature to improve harvest yields by controlling insects' populations or confusing them with scents and colors that force them to move on.

You can also use companion plants to attract beneficial insects to the garden, which prey on and devour the pests that destroy your plants. While the predator insects are busy controlling pest populations, they are also helping to pollinate your garden.

Pesky insects will often arrive in your garden via the wind currents, so strategic planting of a few tall hedges could help stave off an infestation.

Dill will catch most spider mites before they can reach your cucumbers, and a tall hedge of sunflowers will filter migrating aphids to more manageable population levels. Plus, dill and sunflowers attract predatory insects that are also partial to nectar and pollen, like lacewings and ladybugs.

Try pairing your vegetables with the following plants to control pest populations:

Catnip - Aphids, beetles, caterpillars, shield bugs

Dill - Same as catnip but also spider mites

Mint - Same as above but also whiteflies

Attract predatory insects like bees, ladybugs, and predatory wasps by pairing the following plants with your vegetables:

  • Borage
  • Cilantro
  • Dill
  • Cosmos
  • Rosemary (very well suited to Arizona climates)
  • Thyme

Controlling Weeds

Growing edible plants is rewarding in many ways. Growing weeds, however, not so much. Carefully pairing vegetables with cover crops that won't drain the nutrients away from your vegetables will suppress most weeds.

You will also be digging the cover crops back into the soil, which will improve your garden's productive capacity.

Carefully choosing your companion plants to control weeds will mean that most of what you are pulling from your garden will serve a purpose.

Disease Detection and Control

It's possible to use certain plants as early detection for diseases and pests. For example, wineries use rose bushes as an early indicator for mildew. Rose bushes will show signs of mildew first, giving vintners an early warning for preventing an outbreak.

Beneficial Plants

Some plants can improve the growing conditions of surrounding plants. For example, parsley and lemon balm are examples of species that add beneficial chemicals to the soil through their roots, acting as stimulants for other plants in the area. Plus, they are also aid in controlling weeds by adding a ground cover.

Many plants use the bacteria in their root system to fix nitrogen from the atmosphere into the soil. Legumes like peas and beans use nitrogen to grow, which is then returned to the earth when the plants are dug back in after harvesting.

Improve Production in a Small Space

Pairing vegetables means you can get more productive capacity out of even a small garden. Companion plants diversify your garden, so you are not growing excessive amounts of one thing while also adding nutrients to the soil and protecting low growing plants.

Using every inch of available ground cover with plants that support each other will also make your garden more water-efficient, an essential feature in hot climates like Arizona.

Companion Planting Tips

Use these pairing ideas to help you increase growing capacity, control insects, and create a low maintenance garden.

Basil

Basil is a popular pairing for many different vegetable crops but is a favorite herb for tomato growers.

Basil is a natural deterrent for whiteflies, hornworms, aphids, and houseflies. Many gardeners also believe that pairing the herb with tomatoes will improve the harvest's flavor.

The evidence is mostly anecdotal and depends on who you talk to; however, there's no denying the two plants grow well together. Basil likes a lot of sun, but the Arizona summer heat can take a toll. Tall tomato plants offer beneficial shade to protect the lower growing and more delicate basil from the afternoon heat.  

Carrots

Carrots will do well when planted near cabbage, chives, chard, spinach, and tomatoes, but don't play well with strawberries. Protect your carrot harvest from carrot flies with onions, leeks, and wormwood.

Corn

Chinch bugs love a bit of corn, so use beans, cucumbers, peas, pumpkins, soybeans, and squash to keep them at bay.

Cabbage and Cauliflower

Keep cabbage and cauliflower away from your strawberry patch. They will do much better when Brussel sprouts, celery, tomatoes, and spinach are planted nearby.

Cucumbers

Cucumbers will do well when in the vicinity of beans, corn, cabbage, sunflowers, early potatoes, and radishes. The radishes will keep the cucumber beetles away, but they can cause blight in your late potatoes, so time your harvest well.

Dill

Broccoli, Brussel sprouts, cabbage cucumber, onions, and lettuce will all enjoy the company of dill, but not carrots. The word on the grapevine is that nearby dill will also improve your favorite cabbage family plant's flavor.

Garlic

Japanese beetles and aphids' aversion to garlic means that garlic is an excellent pairing for cabbage, cane fruits, roses, tomatoes, and fruit trees. Avoid planting garlic near beans, peas, and strawberries because it will stunt their growth.

More Plant Pairing Gardening Tips

Rather than planting an entire row of the same plant that make it more convenient for insect pests, try mixing it up by interspersing your crop with plants that are known to repel insects or fix nitrogen.

Rotating your crops every year is an excellent strategy for preventing disease and enriching your soil. Try heavy feeders like tomatoes and corn one year and light feeders like chard, beets, and carrots the next. Follow those up with legumes like peas and beans to refresh the soil with nitrogen for a bountiful harvest the following year.

Pairing Vegetables in Arizona

Pairing vegetables with beneficial plants will help you grow a more productive harvest in a garden that requires less maintenance and manual labor to maintain. You will also use fewer or even no chemicals to control pests and weeds and naturally enrich your soil when you follow a few simple companion planting guidelines.


References:

[1] https://cals.arizona.edu/cochise/mg/best-friends-brief-guide-companion-planting-part-1

[2] https://www.mrfothergills.com.au/pages/post-companion-planting/

[3] https://summerwindsnursery.com/az/plant-list/gardens/companion-planting

[4] https://www.motherearthnews.com/organic-gardening/gardening-techniques/companion-planting-zm0z18amzphe

[5] https://todayshomeowner.com/does-planting-basil-near-tomato-plants-repel-insects/