Using crop rotation for a healthy garden

Rotating where plants are in your garden is a cultural practice that can reduce weed production, increase soil health, help with disease and insect management, improve soil structure, and increase yield and quality of produce. When plants are put in the same location year after year soil-borne pathogens tend to build up. Using crop rotations can reduce the use of chemical control of insects, weeds, and fungi.

The principle of crop rotation is to plant a crop in a different place each year. Rotating crops disrupt pathogens, insects, and nematodes by removing the host required to complete their life cycle. Because pests can remain in the soil, it is recommended that a crop should only be planted in one place a maximum of once every three years.

Each vegetable can be classified into a particular plant family. Plants belonging to the same family are often susceptible to similar pests and diseases. Rotating crops helps to reduce pressure from pests and parthenogens. Additionally, plants in the same family tend to directly impact the soil’s fertility in an area. Crop rotation can even out the loss of different soil nutrients and allow time for nutrients to be replenished.

How do I plan for crop rotation in my garden?

Your plan should be based on the types of vegetables you grow. Vegetable crops from the same plant family should not be planted in the same area of the garden year after year. Divide your garden into growing zones. Raised gardens are a simple way to divide your garden into zones, but you don’t need physical barriers to divide your garden. If you are trying to have a three-year rotation, divide your garden into three zones.

Group plant families into one of the three zones. Be sure to provide enough space between plants to avoid the spread of disease and pests. Each family has different nutrient needs, so plan accordingly. The pea family produces high levels of nitrogen, the grass family (corn) uses a lot. A common rotation is to follow the pea family with the grass family to utilize the high levels of nitrogen. The Solanaceae family will use high levels of nitrogen, but when it has those high levels of nitrogen it increases vegetative growth and reduces fruiting. As a result, most gardeners plan to have the Solanaceae family follow the grass family.

Grouping plant families together is often called companion planting. Companion planting involves strategically placing plants close to each other to maximize their mutual benefits and minimize potential negative interactions. While there are general guidelines for companion planting, it’s important to note that specific plant interactions can vary based on factors like soil conditions, climate and regional variations. Additionally, the science behind companion planting is not always well-established, and anecdotal evidence plays a significant role in traditional recommendations.

Just a few recommendations when considering companion planting. Plants of the same family should be spread throughout the zone. For example, tomatoes and potatoes should not be planted close together because they can spread diseases like late blight to each other. Another example is within the Brassicaceae family, we try to avoid planting broccoli, cabbage, cauliflower and kale next to each other to minimize the risk of sharing common pests like cabbage worms.

Onions, garlic, leeks and chives should not be planted next to peas and beans, as the peas and beans will inhibit the growth of the onion family.

Experimenting in your own garden will provide the best results. Make sure to make and record observations throughout the growing season and adjust your rotation to meet your needs each year.