Originally published March 22, 2025 in the Yakima Herald-Republic. Minor edits have been made for web publication and accessibility.
by Angie Kivett
Crop rotation is the practice of planting different crops sequentially on the same plot to improve soil health, optimize nutrients in the soil, and fight pests and weeds. We’ll get to that, but first, a bit of personal gardening history.
When my husband and I moved into our home 19 years ago, there was a big fenced backyard with 3 box garden beds and an established row of raspberry bushes. We were excited about the prospects of growing our own food.
We didn’t know anything about growing a garden but we were determined to try. Friends that had a garden told us to grow a salsa garden: tomatoes, bell peppers, jalapenos, and onions. That sounded great to us.
We had success with our little salsa garden and wanted to add cucumbers and zucchini.
We were unaware of how much more room we would need.
So, we took the inner walls of the beds out and made one giant garden box. We planted our tomatoes in the back rows, peppers in front of those, cucumbers in the front left corner, and zucchini in the front right corner.
Things grew well for several seasons. We got alpaca poop from friends, and thought we were great first-time gardeners. Season after season; tomatoes in the back, peppers in front of those, cukes in the front left corner, and zucchini in the front right corner.
Eventually, things started going not so well. Our tomato yields were less than usual. Our peppers were smaller than what we normally got and we had less of them, as well. Even our relentless zucchini harvest had dropped significantly. We thought, “We haven’t had any manure from anyone in a few years. That must be it.”
Or maybe the late spring was the culprit, or the smoke a couple of summers in a row.
It was not until just recently I heard about crop rotation. I did not know why that would be an important thing to do.
The type of vegetable grown has a direct effect on soil fertility. Some vegetables, such as tomatoes and others in the Solanaceae family, feed heavily on soil nutrients. Other crops, such as herbs and root vegetables, are light feeders. Some crops, like legumes, add nitrogen to the soil and are soil builders.
Soil-borne diseases can build up after years of growing the same plants in the same place. Some pathogens can cause problems like wilting, yellowing, and rotting. One especially disgusting fungal disease is corn smut. I dare you to look up a picture of it on the internet.
Vegetables of the same family grown year after year in the same place provide insect pests with a reliable food source. Planting a different vegetable family instead in that space removes that food source for that particular pest.
Crop rotation can break the life cycle of weeds adapted to the small ecological niche imposed by continuous planting of the same crop.
To keep track of your rotations, a garden journal including planting maps for each year, is helpful. A 3-4 year rotation cycle is recommended.
The common vegetable families are:
CRUCIFERS: cabbage, broccoli, cauliflower, turnip, radish, kohlrabi, and mustard
CURCUBITS: melons, cucumbers, squash
SOLANACEOUS: tomatoes, peppers, eggplant, potatoes
LEGUMES: beans and peas
You can learn more about crop rotation at these links:
WSU pub: Crop Rotation in Home Gardens.pdf
WSU pub: Crop Rotation in the Home Garden.pdf
Feel free to contact the Master Gardener Answer Clinic in Yakima at 509-574-1604 or email askamastergardener@yakimamg.org anytime you have a gardening question.