Arizona Climate-Smart Practices Explained: Crop Rotation

Did you know alternating growing different crops in the same soil can help with producing larger, tastier and more nutritious harvests? This practice is called crop rotation, and it is one way Duncan Family Farms ensures successful, delicious yields of their organic produce. 

Crop rotation is one of the sustainable farming methods highlighted by the Arizona Climate-Smart Practices Program, a group of partners helping more farmers and ranchers transition to climate-friendly growing practices. Some of these partners are dubbed early adopters, as they have already been using these practices for many years and will assist other producers in adopting these practices in ways that best fit their farming and ranching context.

As food eaters, parents, and community members, we all want to live in a stable environment with access to healthy food. By learning more about and supporting producers using climate-smart practices, we can all play a role in ensuring that the future of food and agriculture in Arizona remains strong. 

Crop rotation, the next Arizona climate-smart practice being highlighted, is another practice that farmers are using to help enhance the quality and diversity of the food that we eat and provide benefits to the soil, land, and water. Keep reading to learn more about this ag practice and how an Arizona farming family business has been using it for decades to grow organic greens and herbs.

Crop Rotation

Crop rotation involves a planned sequence of alternating crops on the same plot of land or area to boost soil health, increase biodiversity, manage nutrient cycling and enhance crop yields naturally. 

By switching and diversifying the types of crops grown on the same field, this practice can disrupt the life cycles of pests and diseases and reduce the use of chemical inputs, such as fungicides, insecticides, and pesticides. Different plants require varying nutrition requirements and can be vulnerable to pests and diseases as they grow. If a farmer plants the same crop in the same place every season and year, as is often commonplace in conventional farming, they are conditionally drawing on the same nutrients from the soil, which can deplete it. Unhealthy soil with less microbial activity can be a breeding ground for pest and disease outbreaks and can also lead to nutrient-deficient soils, which can require the use of chemical fertilizers. Crop rotation helps return nutrients to the soil without using synthetic inputs.

The age-old practice of rotating crops can help ensure that ag lands are fertile and productive for generations to come, allowing us to continue eating healthy food. 

Arizona Climate-Smart Practices in Action: Duncan Family Farms

Duncan Family Farms has been growing organic produce in Arizona since 1992. As a partner on the Arizona Climate-Smart practices program and an early adopter of climate-friendly practices, the farm exemplifies how to use agriculture practices that benefit the soil, the crops being grown and potentially reducing the amount of certified organic pesticides they will need to apply. 

Lauren Etchart, who holds a M.S. in Agronomy and is the Sales and Marketing Specialist with Duncan Family Farms, explains that using climate-friendly practices like crop rotation are part of an intentional business plan strategy: “Because Duncan Family Farms is an organic farm operation, crop rotation is an integral part of the company’s business model. Rotating crops helps with Integrated Pest Management (IPM), as it breaks up pest and disease cycles. Crop rotation is one of the pillars used for effective IPM, and it can reduce the need for organic pesticide intervention.”

Duncan Family Farms grows organic microgreens, specialty vegetables, culinary herbs, baby leaf greens including red and green oaks, red and green chard, kale, arugula, and spinach. 

Etchart explains that they have 2.5 crop cycles (seed, plant, and harvest) in a winter season and perform 2-3 crop rotations per field. For example, they might plant spinach, followed by kale, and then finally arugula, as this is an ideal crop rotation for their needs. Since they are growing baby leaf greens, the crops grow very fast, usually within an average of 45 days cycle. Planting typically starts in September, and the last harvest is usually complete by mid-May. 

Duncan Family Farms also does crop rotations in some of their greenhouses and hoop houses, where they grow basil in rotation with mustard greens. They plan their rotation based on disease pressure, what nutrients are needed for soil health and which crops can complement each other. 

During summer months, Duncan Family Farm focuses on rotating cover crops for several reasons.

“We rotate to a cover crop in the summer to catch nutrients otherwise leached into lower soil profiles and into our water systems. Cover crops also keep the ground covered, reducing water and wind erosion. They keep our soil biologically active by feeding the microorganisms all summer long in preparation for the fall cash crop. Cover crops roots help reduce compacted soil and increase water infiltration, and the cover crop biomass suppresses weeds and ultimately increases soil organic matter once the cover crop has been shredded,” says Etchart.

sorghum sudangrass

crop rotation and cover crop planted in spring

During hot summer months, their farm fields can be seen covered with dark green sorghum sudangrass, a drought tolerant plant with long roots that can help suppress weeds and add organic matter to the soil.

The decisions and practices that Duncan Family Farms uses are designed around building and maintaining healthy soil, growing high yield food crops, and organically managing pest and disease issues.

“We have to be really wise about crop rotation. If we get a disease, we have to combat it using organic pesticides as our last line of defense,” Etchart explains. “Crop rotation ensures we aren’t depleting the soil by continuously growing crops with the same nutrient requirements. “Unhealthy, nutrient-deficient soils, and therefore crops, can be an open invitation for pests and disease. Diversifying crop rotations also means our soil microorganisms are feeding on different types of organic residues, which has been shown to increase overall soil health. Healthier soils means healthier crops, higher yields, and less pest and disease pressure.”

By integrating crop rotation alongside cover crops, Duncan Family Farms has been able to produce nutritious, organic food for people while also feeding the diverse microbial communities in the soil through environmentally-sensitive farming techniques. 

To Learn More & Get Involved:

  • Sign-up for Local First Arizona’s Food Systems newsletter that will be spotlighting producers using climate-smart practices and highlighting ways to support them

arizona farmingDanielle Corralclimate-smart practices, climate smart, Duncan Family Farms