Rotating crops in your garden is essential to prevent pests, diseases, and nutrient depletion, ensuring healthier plants and better harvests.
Updated: January 27, 2025
I love winter squash. The golden flesh of ripe butternut squash makes a warm and tasty dish on a cold autumn or winter evening. They are easy to grow and store, and I put in a hill of them every year. This past year, though, I made a rookie gardener mistake. I planted them in the same spot I grew them the year before and the year before that.
In late summer, I went out to weed and admire the large ripening gourds. Instead, I found a scene from a horror movie. My vines and gourds were swarming with squash bugs. When all was said and done, I lost half my crop to them over the next few weeks. I had neglected to follow a primary gardening dictum: rotate your crops!
Every fruit and vegetable has natural enemies: insects, rodents, birds, and various diseases. We grow these plants for our benefit, and the unending game we play is to protect them from others who find them just as delectable. We can use mechanical means like fences and netting for protection from larger animals or birds. Still, insects and diseases are harder to keep out. The best strategy is to move – or rotate frequently – your crops to another spot every year or two.
Once an insect pest or disease finds a spot with its favorite food in your garden, it will move in and stay. The first year may not be too bad, but the food gives these predators enough resources to multiply rapidly. If their offspring can survive over the winter – and many do – a larger population will wake up the following summer ready to feed. Planting your crop in a different location is like moving with no forwarding address. It will take the pests or microbes time to find your crop and give you a year or two respite. If you make crop rotation a habit, you should be able to control many infestation and disease problems.
Unfortunately, many insect pests and diseases we encounter will feast on fruits or vegetables belonging to the same plant family. In the case of squash bugs, they love members of the cucurbit (or gourd) family, which includes cucumbers, melons, and all manner of squash, both summer and winter and gourds. Planting cucumbers or melons in a spot recently vacated by squash, or vice versa, will lead to the same problems, so it’s essential to consider this in any rotation plan.
Rotating your crops will also result in healthier plants, fruit, and soil. Every plant takes up a specific cocktail of nutrients from the soil. The major (or macro) plant nutrients are nitrogen, phosphorus, and potassium. Each plant type will deplete these at a different rate (although some, like peas, put nitrogen back!). Plants also require many micro-nutrients, like iron, zinc, boron, and others.
Soil is not an inexhaustible source of nutrients, and replanting the same crops in the same place will eventually exhaust one or more. Think of the soil as an inkjet printer with many nutrient cartridges. If most of your prints are heavy on red ink, it won’t take long before the colors get weird, and you must recharge the cartridge. Rotating crops and periodic additions of compost or fertilizer will give the soil a chance to recover from the specific nutrient depletions of a given plant type. Your plants will be healthier, better able to resist diseases and pests, and give better fruit.
Author
Michael Shepard
Master Gardener
Columbia County
