Four Year Crop Rotation Plant from Allotment Vegetable Growing Advice

The Four Year Crop Rotation

As with the three year crop rotations and five year crop rotations, we divide our plot up after allowing for the permanent beds of comfrey, asparagus and rhubarb. In this case into four beds or areas.

We start the preceding winter by adding manure to the first plot, which will have potatoes planted in it. The second plot will be limed heavily to take it up to neutral and the other plots will have compost as available.

On heavy clay soils you will probably be digging over each winter to allow the frost's freezing and thawing action to break up the soil. With other soils it would be a good idea to sow an over-wintering green manure crop to hold nutrients that would be washed away in the rain.

The green manure can be dug into the soil in the spring to release those nutrients and improve the soil's humus level with the organic matter. On really light soils a green manure is vital to build good condition and adding the manure or the lime in early spring after digging in the green manure is suggested.

The other two plots can be split with the legumes, beans and peas taking one plot and the onion family taking the other.

Four Year Crop Rotation Plan
	Year 1	Year 2	Year 3	Year 4
Plot 1	Potatoes followed by lime	Legumes (Beans) followed by additional lime	Brassicas	Onions & Roots followed by manure
Plot 2	Legumes (Beans) followed by additional lime	Brassicas	Onions & Roots followed by manure	Potatoes followed by lime
Plot 3	Brassicas	Onions & Roots followed by manure	Potatoes followed by lime	Legumes (Beans) followed by additional lime
Plot 4	Onions & Roots followed by manure	Potatoes followed by lime	Legumes (Beans) followed by additional lime	Brassicas

If you have enough land that you are not pushing for maximum crops and you don't have clubroot to worry about, follow your potatoes with a green manure of mustard. The use of mustard as a green manure after the early potatoes hardens the cysts that contains the next generation of potato eelworm so preventing them from hatching.

Since the bean family tend to fix nitrogen rather than exhaust it, these go well before the brassicas. L D Hills suggested that the bean family should follow the lime with the brassicas on the second year after liming. Since most of the expert brassica growers suggest liming immediately before brassicas, you could go lime, legume, additional lime, brassica if you wish.

The onions and the root crops share the last bed in the rotation. Crops like the cucurbits and sweetcorn fill in the gaps.

The benefit of this four course rotation is the gap between each crop, especially the cabbages and potatoes, occupying the same ground is extended and the other crops in the rotation have more flexibility in position.

A lot will depend on your actual requirements when you set up and use a rotation plan. The important part of your crop rotation is to keep things apart for as long as possible. Keeping a plan of your plot and marking in what has been planted where will prove of great value over the years because you are unlikely to remember what was planted where after two years.

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Vegetable Growing Advice - Crop Rotation

The Four Year Crop Rotation

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