Rotate Your Vegetables!
Now is the time for getting our summer vegetables planted in the garden. Those summer vegetables include tomatoes, peppers, beans, squash, and many others. As we plant our vegetable gardens, it is important to think about crop rotation.
Crop rotation is a practice that has been around for years as a way to change planting locations of plants which reduces pest problems and improves soil fertility. For a vegetable garden, crop rotation would be changing the planting location of vegetables each season. Vegetables that belong to the same family often are susceptible to the same types of insects and plant diseases along with having similar nutrient requirements. When vegetables in the same family are grown in the same location year after year, the insect and plant disease populations increase in those areas because you have provided them with a reliable food sources. Vegetables in the same family are similar in the amount of nutrients they extract from the soil, so over time planting the same vegetables in the same spot can reduce certain nutrients in the soil. If the same family of vegetables is planted every year in the same location, insect and disease problems continue to increase and soil fertility drops. Using pesticides and fertilizer could provide little help but over time they would not be able to keep up with the increasing problems.
So what do you need to know when rotating vegetables in a garden? Each vegetable can be classified into families based on common characteristics. If you know which vegetables are in the same family then you can avoid planting the same family of vegetables in the same location. Below are the main families along with the families’ scientific name and which vegetables are in them:
- Lily Family (Alliaceae): Chives, Garlic, Leek, Onion
- Parsley Family (Apiaceae): Carrot, Celery, Parsley, Parsnip
- Composite Family (Asteraceae): Endive, Lettuce, Sunflower
- Mustard Family (Brassicaceae): Broccoli, Brussels sprouts, Cabbage, Cauliflower, Collard, Kale, Mustard greens, Radish, Rutabaga, Turnip
- Goosefoot Family (Chenopodiaceae): Beet, Spinach, Swiss Chard
- Gourd Family (Cucurbitaceae): Cantaloupe, Cucumber, Pumpkin, Summer Squash, Watermelon, Winter Squash
- Pea Family (Fabaceae): Bush bean, Lima bean, Pea, Pole bean
- Mallow Family (Malvaceae): Okra
- Grass Family (Poaceae): Ornamental corn, Popcorn, Sweet Corn
- Nightshade Family (Solanaceae): Eggplant, Pepper, Potato, Tomato
To give an example of crop rotation, if tomatoes were planted in the front of your garden last year then this year you would want to avoid planting tomatoes along with peppers, potatoes, and eggplant in that same spot because they are all in the nightshade (Solanaceae) family. To remember where things are planted every year, it can be helpful to make a simple map of where vegetables are located in your garden each year. Then the following year you will know how to rotate your vegetables. It can become difficult to have crop rotation in a small garden area but at least avoiding planting the same vegetable each year in an area of the garden can help manage pest problems and improve the soil.
As you plant in your vegetable garden keep track of where you plant things then next year you will know how to rotate your vegetables. This will not only help reduce pest problems but is also a great way to improve the soil.
Jessica Strickland is an Agriculture Extension Agent, specializing in horticulture for North Carolina Cooperative Extension in Wayne County.