* Grow all year long for continuous crops and flowers,
* Balance plants and soil nutrients, and reduce waste,
* Avoid build up of pests and disease.
Crop rotation essentially involves moving plants of the same kind to new ground every year. Below I outline my suggested organic gardening crop rotation. This shows how to get high productivity with continuous end-to-end growing and intercropping of suitable plants.
Why is Crop Rotation Necessary?
When you grow a crop in the same ground year after year, specific pests readily increase in numbers. And when some pests, such as potato eelworm, are allowed to proliferate they can remain a problem for years to come and prevent further potato growing. That would be a gardening catastrophy indeed.
But you can prevent these pests becoming a problem by moving your crop to another site in your garden. So when the pest eggs hatch the food plant needed to sustain them has gone. For example, with 4 different crops on 4 plots, each plot grows the same crop only once every 4 years. That's really simple and, neglecting rotation is just too risky.
A Change Is As Good As A Rest
And there's another advantage to crop rotation. Because, crops of a similar kind with similar root systems take the same nutrients from the same volume of soil. Whereas different crop types can take different nutrients at different soil depths. Some crops can even add nutrients to the soil to help make up for nutrient loss.
Therefore rotating your crops makes maximum use of soil nutrients before they need replacing and even allows some nutrient replenishment. However, it is important to remember that continuous end-to-end growing will cause a loss in productivity. Therefore your organic crop rotation should also allow for rest periods, including growing green manures and the application of composted animal manure.
My Guidelines For Organic Crop Rotation
Grow plants of the same family together (see plant family table below) and follow them with plants of a different plant family of course...
But, avoid large monocultures which can also attract pests. Interplant rows with companion crops such as spring onion in between carrots. This is effective against carrot root fly,
After crops that are preceded by gross feeding, use "nitrogen lifting" green manures to mop surplus nutrients if there's no crop to follow on,
I use beans or a "nitrogen fixing" green manure before and after brassicas,
I use one of:- animal manure, garden compost and green manure every year and roughly rotate which of the three is applied to a particular bed,
After digging in green manures follow them with large seeds such as beans, or by direct planting out e.g. seed potatoes, onion sets, plants grown in modules... etc... link to green manures explains this.
To maintain fertility during continuous production it is important to supplement nutrients with organic fertilizers. These come from organic waste streams as explained on the above link,
A long rotation cycle - 6 years or so - is important in protecting crops like potatoes. Growing in tubs helps to give the small gardens a rest,
A simple 4 plot sequence of crop rotation might be:
The above however, fails to demonstrate how crops can follow on in a continuous sequence. So my diagram below - if a little complicated - tries to show how to follow on by correct timing and intercropping.
Growing Order For Continuous Production
Every gardener has their own favourite crops and you must grow what you like to eat. A common mistake is to grow stuff that for one reason or another you have to give away. The diagram below can only be a guide. At least I hope it illustrates the potential riches of garden space and helps you better organise your organic gardening.
You should also be able to see how combinations of crops can be grown in the same plot. And you can see that some plots split to go different ways depending on your choice of follow on. All the seeds you need for growing are on the links at the end.
Early potatoes given wide inter-row spacing and broad beans grown between,
Potatoes followed either by Japaneese Onions or Spring Cabbage.
Crops such as artichoke, asparagus and rhubarb need a more or less permanent location and will only be moved after several years. But you should really try to grow fresh plants from stock every few years to plant into freshly manured and dug soil.
Strawberries are another crop that need rotating every 3 or 4 years. Propagate from suckers after year 2 and replace with a new row in year 3 or 4.
Sweet corn, Courgette, Pumpkin have also been described as oddments but they fit well with beans as companion crops and they should be rotated.
Additional Considerations And Constraints
When planning your garden beds you will also consider grouping plants that need similar kinds of protection. Examples include bird and insect protection netting, and frost protection with cloches and tunnels.
Crop Rotation in Greenhouses and Polytunnels
This is often neglected but remains important especially for controlling disease in confined spaces.
You can rest these growing beds by using alternatives such as containers, grow bags or even hanging baskets all of which are portable. Also, roots remaining from winter cut crops, as well as green manures turned in, will add something to these permanent beds. And by using alternative crops the break needn't be wasted. As always manure and garden compost are the keys to fertility.
Find The Seeds And Plants For Your Crop Rotation Below