UNITED STATES—Vegetable plants are mostly unnaturally productive. Extensive breeding compels them to yield fruits and vegetative parts that are bigger, better and more abundant that what their ancestors produced. Increased production increases their reliance on resources. Without crop rotation, some sorts of vegetable plants noticeably deplete some of what they need.
Rotation, which is the same as crop rotation or garden rotation, is a technique of growing vegetables where different types of vegetables grew previously. In other words, one type of vegetable does not grow in any one place for too long. Some vegetables may produce well in some types of soil for a few years. More consumptive types prefer annual rotation.
This technique disrupts the depletion of particular nutrients that particular types of plants crave. It also allows for replenishment of depleted nutrients in the absences of plants that cause such depletion. Furthermore, some soil borne pathogens find this active cycling to be disruptive. Eventually, plants that cycled out can cycle back into a particular situation.
Everyone, including vegetable plants, has different taste.
Tomato plants are particularly consumptive, so appreciate rotation in many types of soils. Eggplant and pepper are related to tomato, so crave many of the same resources, even if they are less consumptive. Therefore, they should not cycle directly into soil relinquished by tomatoes. Unrelated vegetables, such as squash, corn or bean, are more appropriate.
Warm season vegetables that are now returning to the garden might appreciate rotation. A bit of research to determine appropriate placement for them may significantly enhance production. It helps to know which vegetables are related, such as mustard, collard, kale, radish and turnip (of Cruciferae Family), or squash and melon (of Cucubitaceae Family).
Because corn is so high, it should grow to the north of a vegetable garden. Unfortunately, rotation may dictate that it grows to the east for a while, or only in portions of the northern edge that it avoided for a while. Pole beans that like to climb wire fences may sometimes need reassignment to different portions of their fence. Peas should follow their example since they are related.
Highlight: Mustard
A few species of mustard came to naturalize in California, and for a few distinct reasons. Some likely grew first as greens in the gardens of the original Spanish Missions. At least one species also provided culinary and medicinal mustard seed. The more prolific types became cover crops and fodder for livestock. Later in history, mustard seed provided oil.
According to legend, Spanish Missionaries established the route of El Camino Real with mustard. After sporadically dropping seed as they traveled between Missions, they could follow the bright yellow bloom by the next winter and find greens to eat. El Camino Real became worn enough to navigate before the mustard dispersed too extensively to assist.
Most but not all species of mustard that are naturalized locally are of the genus Brassica. Wild turnip and wild radish provide similar greens, but are generally more likely to bloom pale pink or pale white, rather than bright yellow. Garden varieties of mustard, which are available as seed or in cell packs, provide delightfully tender new leaves with mild flavor.
Horticulturist Tony Tomeo can be contacted at tonytomeo.com.