Crop rotation is the process of growing vegetables in their respective families and moving the families around a plot in a specific sequence so they are not grown on the same piece of land for at least 3 years.
Vegetable Family Table
Vegetable families are classified into mainly 3 types:
|Examples||Cabbage, Broccoli, Cauliflower||Pea, Bean – Broad, Borlotti, Runner, French||Beetroot, Carrots, Onions, Garlic||Potatoes & Tomatoes|
|Notes||Although these are not technically from the same family they are all treated roughly the same||Although technically roots, these are generally grown in their own plot as they are grown in large quantities|
|Soil requirements||Nitrogen rich which may need liming||Well drained but moisture retentive not Nitrogen rich.||Stone-free, fine tilth but not freshly manured as causes forking||high organic matter without lime|
|Soil benefits||None||Leaves behind Nitrogen for following crop||Great for breaking up soil structure||Good at weed surpression & breaking up soil structure|
Crop rotation has been practiced for centuries and has a number of excellent benefits, it helps to avoid the build up of soil-borne pests and diseases that might affect one particular crop; different families leave behind nutrients and can also draw up minerals that help to feed the following crop; and minimises the use of fertilisers which is good for organic cropping. It is possible to use a 3 year crop rotation programme but if you require a lot of potatoes it is best to split your plot into 4 sections. Potatoes should be grouped with roots in a 3 year plan.
4 Year Crop Rotation Plan
Each bed/area will remain the same number.
|Year 1||Year 2||Year 3||Year 4|
|Bed 1||Potatoes (followed by Leeks or Lettuce in summer)||Legumes||Brassicas||Roots|
|Bed 2||Roots (Carrots, Beetroot, Onions plus Sweetcorn)||Potatoes||Legumes||Brassicas|
|Bed 3||Brassicas (Cabbage, Broccoli, Sprouts)||Roots||Potatoes||Legumes|
|Bed 4||Legumes (Peas, Beans – Broad, Borlotti, French & Runner)||Brassicas||Roots||Potatoes|
N.B. If it is very difficult to rotate your crops just try not to grow onions or brassicas in the same spot 2 years running as their soil-borne pests and diseases develop quickly. There are of course some veg that require permanent beds and do not require moving e.g. Asparagus and rhubarb (many class this as a fruit).
Helpful hintsSome vegetables can fit into any crop rotation position, e.g.
- Courgettes & Squash – particularly good with potatoes as they like lots of manure and early/second early potatoes are harvested before these get too large.
- Lettuce is a great catch crop sown in between potato ridges but will fit anywhere.
- Sweetcorn fits well into roots but will do well elsewhere too.
- Leeks that have been planted in a seed bed can be transplanted into the potatoe bed once the potatoes have been dug up in the summer.