What is Crop Rotation?
Crop rotation is a straightforward concept: It is the practice of not growing the same crops in the same location in consecutive years.
Rotating crops this way helps avoid having pests and diseases build up in the soil by avoiding planting the same veggies in the same area every year. When you relocate the crop, the pest or disease loses its host.
It’s recommended to rotate a vegetable or a whole vegetable family so that it grows in a specified area of your home garden once every 3 to 4 years.
For instance, if you grow tomatoes in the same garden bed each year, those pests or diseases are more likely to impact this year’s harvest as well. Therefore, you would plant them in a different bed the next season.
So you would plant a different kind of crop, like chard, broccoli, or carrots, in that first bed instead of tomatoes. Finally, after the third year, you can replant tomatoes in their original spot.
Crop rotation serves multiple functions, including preserving soil health and providing the nutrients that various plants require. Let’s look at the benefits to understand why you’d want to consider rotating crops in your home garden.
How to Get Started with Crop Rotation
Step 1: Understanding Crop families
So how do you know which vegetables should follow in your garden? There are charts that help. But the principles behind crop rotation are fairly straightforward.
The crop you choose to follow the previously grown crop should differ in lifecycle and associated cultural practices such as the rooting, soil nutrient needs, and moisture needs of various families of plants.
Knowing the family of plants each vegetable belongs in — onions, peas, grasses (like corn), gourds, nightshades (peppers tomatoes, eggplant) — is invaluable.
Here are the major crop family groupings that should be planted together and then rotated to another crop family:
Leguminosae (pea and bean family)
This crop family includes all types of peas and beans including green beans, green peas, southern peas, peanuts, and soybeans.
As you may know, all legumes are soil fixers and improve soil quality by adding nitrogen back into them.
Brassicaceae (cabbage family)
This family includes Calabrese, Brussels sprout, broccoli, cabbage, kohl rabi, cauliflower, kale, rocket, mizuna, pak choi, radish, arugula, rutabaga, and turnip.
All these crops share pest issues and often need to be netted to block cabbage moths. Similarly, they require nitrogen-rich soil. It’s recommended to plant after the legume (bean) family.
Solanaceae (nightshade family)
This includes potato, tomato, peppers, and eggplant.
These plants are considered heavy feeders which need rich soil. They are also affected by the same diseases. And another important top to remember is that it’s always recommended to never plant tomatoes after potatoes.
Alliums (onion family)
This family includes garlic, shallot, all varieties of onions, chives, and leeks.
Umbelliferae (carrot family)
This family includes celery, celeriac, cilantro, fennel, carrot, parsnip, parsley, and dill.
Cucurbitaceae (squash and marrow family)
This crop family includes zucchini, cucumber, marrow, melon, pumpkin, squash, and couchette. They’re all considered heavy feeders that grow best in rich soil.
Chenopodiaceae (beetroot family)
This crop family includes Swiss chard, perpetual spinach, true spinach, and beetroot
Miscellaneous (non-rotation annual crops)
These include basil, lettuce, endive, cress, sweet corn, okra, salsify, scorzonera, New Zealand spinach, corn salad, chicory
Other Crop Family Groups
There are many more families, but some, like corn, okra, and sweet potatoes, only have one member that we would grow in a home garden.
Some plant families can be grown in close proximity to one another in a small garden; for example, brassicas, legumes, and lettuce can all be grown together to promote crop rotation.
Step 2: Planning, Planting, and Recording
The second step involves planning out which crops to grow, planting them, as well as recording where they were planted.Let’s first understand how to use the plant families. The list we’ve mentioned above is in a particular order. The first time you plant you can start with the legume and cabbage family.
After you’re done harvesting them, then the first family should be planted, and it keeps continuing down the list. And this is how you can easily rotate crops! The other important thing to keep in mind is remembering where your crops were planted in previous years. This is critical to planning where the crops will go come next spring.
This is where a garden journal is invaluable, especially one with garden layouts drawn (as I like to do) on graph paper. Your memory might be better than mine, but I’m always surprised by how confused I can be about where things were planted last year.
This happens to the best of us, especially if we’ve been gardening the same plot for more than a few years. When you draw up your garden plan, it’s wise to consult the plans you drew from previous years if you have them. With a journal, you will.
Step 3: Switching to the Next Family
While a three-year rotation is recommended, even just alternating the same crops every other year — often a necessity in small garden plots — is worthwhile.
And while it’s recommended that you move crop plantings as far away as possible from their previous location, even a foot or two can make a difference. Some gardeners, compartmentalize their plots, moving them from A to B to C (and D and beyond) every year.
This makes for easily remembered rotations. Dividing your garden space into quadrants and then rotating crops through the various quadrants is an easy way to keep up with crop rotation.
Step 4: Remember to Alternate Between Heavy and Light Feeders
Crop rotation also includes alternating heavy feeders with light feeders to lessen nutritional demands on your soil.Heavy feeders are those, as the same suggests, that consume a lot of nutrients. Lighter feeders, on the other hand, consume fewer nutrients. Alternating between the two puts less stress on the soil
Heavy feeders, such as corn, lettuce, broccoli, tomatoes, and cucumbers, require a great deal of nitrogen in order to produce blooms, fruit, and leaves. Plant less-demanding crops like carrots, potatoes, beets, or onions to give their beds a break.To add nitrogen naturally, plant legumes like peas or beans. Their roots have bacteria that fix nitrogen. Don’t pull these plants out of the ground in the fall. Instead, cut them off and let the roots decompose in the soil. They will leave behind nitrogen that can be used by plants the following year.
There you have it, that’s all you need to know to successfully do crop rotation in your home gardens.