Crop rotation is a simple procedure that involves not planting the same crop in the same soil for a period of years. Depending on space available, the minimum recommended time is two years, while some gardeners prefer a rotation of up to six years.

The purpose is to prevent a build up of pathogens in the soil which can infect and re-infect particular families of plants. Another purpose is that plants absorb different quantities of soil nutrients, and repeated plantings will quickly deplete the soil. Crop rotation therefore allows for a more balanced soil fertility and microbial balance.

Firstly, you need to know how plants are related, ie. What family they belong to. Below is a list of some of the more common vegetables, sorted into family groupings.  The basic principle of crop rotation is to not grow members of the same family, in the same soil, in consecutive seasons.

Cruciferaea
Kale, Cauliflower, Cabbage, Broccoli, Brussels Sprouts, Kohl Rabi, Radish, Swede, Turnip, Mustard

Solanaceae
Potatoes, Tomatoes, Eggplant, Capsicum, Chillies, Tobacco

Amaryllidaceae
Chives, Garlic, Leek, Onion, Spring Onion, Shallots

Chenapodiaceae
Beetroot, Silverbeet, Spinach

Gramineae
Corn

Compositeae
Globe Artichoke, Jerusalem Artichoke, Lettuce, Endive

Leguminoseae
Peas, Beans, Broad Beans, Snow Peas

Apiaceae
Carrots, Celery, Celeriac, Coriander, Dill, Parsley, Parnsip

Curcurbitaceae
Cucumber, Choko, Marrow, Melons, Pumpkin, Squash, Zucchini, Gourds

What to grow, Where?

• Make a list of the vegetables you would like to grow for the season (Autumn/Winter vegetables or Spring/Summer vegetables), then group these together in family groups.

• Think about your garden area, and divide it up according to the number of family groups you have selected. This can be as simple as allocating a number of rows in a traditional vegetable plot, or you can use completely separate beds in opposite corners of your garden!

• Decide on an annual ordering sequence for placement of the family groups (see example following) and record this in a garden diary or notebook which you can keep handy. Record your successes and failures so you can alter plans if required, based on your experience.

• A common vegetable to start the sequence are legumes. These plants have the ability to fix atmospheric nitrogen and store it in the soil in a form that is accessible to plants. It is particularly beneficial to allow these plants to break down into the soil once their productive life is over. This helps to add nitrogen rich organic matter to the bed.

• With all of this ‘extra’ nitrogen available, it makes sense to follow this crop with a nitrogen hungry one to reap the benefits. Good examples are corn or leafy green vegetables.

• Another general rule is to grow root crop vegetables after particularly hungry crops, as vegetables in the carrot or onion family tend to be good nutrient scavengers and can be grown in comparatively poorer soil than other crops.

• Don’t forget to improve your soil along the way! You still need to feed your plants with all the goodies like compost, manure, worm castings and the odd liquid feed to get the best from your garden.

• If you have the space, growing a green manure crop somewhere in the cycle can be an advantage. This helps to replenish nitrogen stores and is an excellent way to build up the organic matter in the soil. (Green Manure is sold by us in a pack of mixed seeds, seasonally available.)

• The more crops you intend to grow, the more complex the overall plan becomes, but don’t despair! There are no hard and fast rules, so just have fun with your garden! If it all seems too hard, scale it right down to making sure you don’t follow with the same crop in the same spot year after year.

• In small gardens, you can try growing certain crops in pots to give you more room, which also serves to rest the soil.

The following example is quite a complex one, done purely as an example. In this scenario, Winter and Summer crops are listed over a five year rotation, for four garden beds. (It would be much simpler if it were over five garden beds, but as you can see from the example there are a few things you can do to cheat the system and double up, still giving considerable periods of time between repeated plantings.)

The vegetables I have chosen for this example are:

Winter Cropping/Autumn Planting
Peas, etc. Potatoes, Broccoli/Cabbage/Cauliflower, Spinach/Beetroot, and a green manure crop.

Summer Cropping/Spring Planting
Corn, Cucumbers/Melons/Pumpkins, etc. Carrots, Tomatoes, Lettuce, Strawberries.

Season/Year	Bed 1	Bed 2	Bed 3	Bed 4
Winter 1	Peas	Potatoes/ Spinach	Broccoli/ Cabbage	Green Manure
Summer 1	Corn	Cucumber/ Melons	Carrots/ Strawberries	Tomatoes/ Lettuce
Winter 2	Potatoes	Broccoli/ Cabbage	Green Manure/ Peas	Spinach
Summer 2	Cucumber/Melons	Carrots	Tomatoes/ Lettuce/Corn	Strawberries
Winter 3	Broccoli/Cabbage	Green Manure	Spinach/ Potatoes	Peas
Summer 3	Carrots	Tomatoes/ Lettuce	Strawberries/ Cucumber	Corn
Winter 4	Green Manure	Spinach/Broccoli	Peas	Potatoes
Summer 4	Tomatoes Lettuce Carrots	Strawberries	Corn	Cucumber/ Melons
Winter 5	Spinach	Peas/Green Manure	Potatoes	Broccoli/ Cabbage
Summer 5	Strawberries Tomatoes	Corn	Cucumber Melons Lettuce	Carrots

Please note:
(Information provided is intended as a guide only – many variable factors such as garden bed location, sunlight, water needs, etc. may need to be considered, and are unique to your own backyard. Above all, have fun! Record your successes and failures as you go along and enjoy the journey!)

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