Developing a Crop Rotation Plan

It’s time for another instalment of our popular ‘Top of the Crops’ Series. This time, we want to help you learn all about crop rotation. If you are planning to grow abundant crops on your land, you need to understand how to develop and implement a crop rotation plan. It really makes all of the difference!

What Is Crop Rotation?

Crop rotation is a system of growing different kinds of crops in sequence in the same field in order to prevent erosion and increase the fertility of the soil. This is necessary, as monocropping (growing the same crop or type of crop) in the same soil will gradually cause the depletion of its nutrients.

Instead, crop rotation helps to balance the problem and increase the fertility of the soil. When one type of crop leaches certain nutrients from the soil, the next season’s crop will add the lost nutrients back. Crop rotation also encourages the proliferation of beneficial bacteria, and prevents the build-up of pests and pathogens.

 

Who Invented Crop Rotation?

It is impossible to state with certainty who invented crop rotation. Those involved in farming and agriculture have known for thousands of years that some form of crop rotation is beneficial for a fertile yield.

The archaeological record shows that farmers in the Ancient Middle East rotated their crops as early as 6000 BC. They may not have known the science behind the practice, but they new it was efficacious. Crop rotation is even referenced in the Bible! In Leviticus Chapter 25, the Israelites are told to observe a “Sabbath of the Land”.[i] This means that every seventh year they would let the field sit fallow, and not even control its insects.

A two-field crop rotation system

In a two-field crop rotation system, half of the available farming land is planted for a year, and the other half lays fallow. Around the 9^th century, most European farmers transitioned to a three-crop rotation.

A three-field crop rotation system

From this point until the century, most European farmers moved onto a three-field crop rotation system. One section would be planted in the fall with rye or wheat, and the planted with oats or barely in the spring. In the second section, beans, peas, or lentils would be grown. The final section would be left fallow for the year. This means that each of the three fields would be left fallow every third year.

The four-field crop rotation system

In the early 16^th century, farmers in Northern Belgium began using a four-field rotation. By the 18^th century, British agriculturalist Charles Townshend popularised this method in the UK. The new system focused on 4 crops (barley, clover, turnips, and wheat) and included a grazing crop and a fodder crop. This meant that livestock could be bred throughout the year. In the early 20^th century, George Washington Carver studied and built upon the four-field method. He taught farmers in the southern US to rotate their most depleting crops (like cotton) with peanuts and peas, which enrich the soil.

 

What Is The Purpose Of Crop Rotation?

Simply put, crop rotation is vital if you want to maintain a healthy level of nutrition in your soil, and boost your yields in the future. Instead of pumping your land with heaps of commercial fertilisers, you can instead use rotation of complementary crops to add nutrients and minerals. Crop rotation is also designed to remove pests and prevent diseases from taking root in your soil.

For instance, a rotation of grazing animals and grass will add nitrogen into your soil. So too will leguminous plants, which have root nodules that are full of nitrogen, which you can then plough back into your soil.

What Are The Benefits Of Crop Rotation?

Crop rotation has many different benefits.[ii] These include:

• It increases the fertility of your soil
• It increases your yield
• It boosts the amount and diversity of nutrients in your soil
• It prevents soil erosion
• It limits the proliferation of fungi, pests, and diseases
• It reduces the number of weeds that grow and flourish
• It improves the soil structure over time
• It removes the need for fertiliser (or lowers the amount you need), and is therefore better for the environment

What Are The Different Types Of Vegetable Families?

Vegetables and fruits can be grouped into 11 main families.[iii] In order to start planning your crop rotation, you need to first divide your garden or fields into three or four (or more) different sections. Using the information below, divide your crops into their family groups. Keep your plant families together, and move them around into different sections every year.[iv]

Umbelliferae – This family includes some poisonous species, including hemlock, as well as many edible vegetables and herbs. It includes caraway, celery dill, anise, garden angelica, carrots, chervil, parsley, coriander, cumin, fennel, and parsnips.

Asteraceae (or Compositae) – a large family, including shrubs and trees. In terms of vegetables, it includes dandelions, artichokes, chamomile, chicory, tarragon, lettuce, and salsify.

Lamiaceae – This family is comprised on plants that secrete essential oils, and have very strong smells. Mint, lemon balm, basil, hyssop, oregano, lavender, rosemary, savoury, sage, and thyme.

Solanaceae – A family of herbaceous plants, trees, shrubs and vines that grow well in tropical regions, including tomatoes, potatoes, aubergine, and bell peppers,

Brassicaceae (or Cruciferae) – This family is comprised of plants four petals in a cross shape and six stamens. It includes cabbage, turnips, watercress, and radishes.

Liliaceae (alliums) – This family includes the alliums asparagus, onions, garlic, chives, shallots, and leeks.

Rosaceae – A family of herbaceous and woody plants, including apples, plums, strawberries, cherries, raspberries, blackberries, and pears.

Cucurbitaceae – This family includes many climbing plants, including melons, pumpkins, squash, and cucumbers.

Chenopodiaceae – Plants with no petals, including beetroot, Swiss chard, and spinach.

Fabaceae (legumes)– This family is also referred to as the pulses, and includes peas, soy, peanuts, fava beans, and lentils.

Poaceae (or Gramineae) – This family includes many grains, but also includes bamboo, rice, corn, wheat, millet, barley, oats, and rye.

Now that you know all about the history of crop rotation and are familiar with its benefits, it’s time to get started on your own![v]

 

Three Year Crop Rotation Plan

Using the vegetable classifications listed above, divide your crops. Here is a sample three year rotation, in which the major crops are potatoes and brassicae. Divide your garden into three sections (or four, in which the fourth section will be perennials, i.e. rhubarb and asparagus).

1^st  Year:
Field or Section 1: Potatoes
Field or Section 2: Fabaceae (legumes), Liliaceae (alliums), and Umbelliferae (roots)
Field or Section 3: Brassicae

2^nd Year:
Field or Section 1: Fabaceae (legumes), Liliaceae (alliums), and Umbelliferae (roots)
Field or Section 2: Brassicae
Field or Section 3: Potatoes

3^rd Year:
Field or Section 1: Brassicae
Field or Section 2: Potatoes

Field or Section 3: Fabaceae (legumes), Liliaceae (alliums), and Umbelliferae (roots)

Four Year Crop Rotation Plan

In this four year rotation example, brassicae and potatoes are less important, and you would like more legumes (which take up more room) and alliums.

1^st Year
Field or Section 1: Fabaceae (legumes)
Field or Section 2: Brassicae
Field or Section 3: Potatoes
Field or Section 4: Liliaceae (alliums) and Umbelliferae (roots)

2^nd Year
Field or Section 1: Brassicae
Field or Section 2: Potatoes
Field or Section 3: Liliaceae (alliums) and Umbelliferae (roots)
Field or Section 4: Fabaceae (legumes)

3^rd Year
Field or Section 1: Potatoes
Field or Section 2: Liliaceae (alliums) and Umbelliferae (roots)
Field or Section 3: Fabaceae (legumes)
Field or Section 4: Brassicae

4^th Year
Field or Section 1: Liliaceae (alliums) and Umbelliferae (roots)
Field or Section 2: Fabaceae (legumes)
Field or Section 3: Brassicae
Field or Section 4: Potatoes

Crop Rotation boosts your yields and reduces the need for fertiliser

Before you reach for the commercial fertiliser, consider using a method that dates back millennia and is easy on the environment. While it takes some planning and thought, once you are in the habit of rotating your crops, you will never go back.  You can always refer to our Top of the Crops guides if you need any help growing your vegetables.

Reference list

[i] http://agriculturerinfo.com/crop-rotation/

[ii] https://www.farmersweekly.co.za/farm-basics/how-to-crop/why-crop-rotation-is-important/

[iii] http://www.fondation-louisbonduelle.org/en/my-vegetable-garden/grouping-vegetables-according-to-plant-families/

[iv] https://www.gardenorganic.org.uk/planting-plan-and-crop-rotation

[v] https://www.rhs.org.uk/advice/profile?pid=124

Agriculturerinfo.com. (2019). Crop rotation – agriculturerinfo.com. [online] Available at: http://agriculturerinfo.com/crop-rotation/ [Accessed 3 Dec. 2019].

Caxton Magazines (2012). Why crop rotation is important. [online] Farmer’s Weekly. Available at: https://www.farmersweekly.co.za/farm-basics/how-to-crop/why-crop-rotation-is-important/.

Gardenorganic.org.uk. (2017). Planting plan and crop rotation | www.gardenorganic.org.uk. [online] Available at: https://www.gardenorganic.org.uk/planting-plan-and-crop-rotation [Accessed 2 Dec. 2019].

Rhs.org.uk. (2019). Crop rotation / RHS Gardening. [online] Available at: https://www.rhs.org.uk/advice/profile?pid=124 [Accessed 2 Dec. 2019].

Rousseau, N. (2016). Grouping Vegetables According to Plant Families. [online] Fondation Louis Bonduelle. Available at: http://www.fondation-louisbonduelle.org/en/my-vegetable-garden/grouping-vegetables-according-to-plant-families/ [Accessed 2 Dec. 2019].

Science History Institute. (2018). George Washington Carver. [online] Available at: https://www.sciencehistory.org/historical-profile/george-washington-carver.