Crop rotation is an essential skill for vegetable gardeners

Crop rotation is an essential skill for vegetable gardeners

Crop rotation is important in maintaining soil health, preventing disease and controlling weeds. It is also useful in helping to optimize productivity.

However, you should think of this more in terms of general rules-of-thumb, rather than a rigid sequence. flexibility is always a good thing.

In working out a rotation, there are a number of plant categories you can group things into that can help in working out the stages in your crop rotation:

Leaf vegetables
Root vegetables
Fruiting vegetables
Onions and garlic
Legumes (or pulses)
Grasses and cereals
non-cereal grains
The last two in this list are not actually stages in the rotation as such. They are actually options to use in the fallow or resting period. It is always tempting to try an increase production by skimping on this or cutting it out of the crop rotation altogether. Try to avoid giving in to this temptation, the longer-term production loss from damage to your soil will be lots worse.

In general, people think of fallow as the end of the crop rotation, but in fact it is the start - its your preparation phase. On many farms, fallow means cultivating and spraying to prevent all growth, but in the garden this is a big "No-No". (In fact, it probably should be on farms as well, but that's another story).

This is the time in the crop rotation to use green manure crops. A good one is Buckwheat. This is a non-cereal grain that is leafy, fast growing and has a dense fibrous root system. It is very good at getting nutrients out of the soil, so when you grow it and turn it into the soil, you are effectively converting unavailable nutrients into a plant-available form.

Another advantage of buckwheat is that its edible. The grain is great for chickens (although you will need to crush it up a bit) and even the leaves and flowers can be used in salads and so forth. However, if you want this as a green manure crop, you should turn it under as soon as it begins flowering.

The next step in the rotation should be a leaf vegetable like lettuce, cabbage, cauliflower, etc. These plants need the most fertile soils.

These are followed by root vegetables like potatoes as there will still be enough nutrition in the soil for them to grow without much fertilizer.

Fruiting vegetables like tomatoes can be used either instead of leaf vegetables or after a root vegetable. If you plant them after a root vegetable, your will need some additional fertilizer, but not too much.

The reason is that the next step in the rotation is to plant onions, shallots or garlic. These vegetables become soft and don't store well if the soil is too fertile. If you are not sure, try the salad versions that are naturally softer anyway.

The last step in crop rotation is to plant a legume like peas or beans. These are nitrogen fixers and will help begin the process of reinvigorating the soil that will continue through the next fallow period. However, you can also use legumes as fruiting vegetables earlier in the rotation, depending on the season, your needs and preferences.

If you do use a legume as a fruiting vegetable and it is going to be grown before an onion crop, then choose French beans as these are the poorest nitrogen fixers of the group.

Of course, crop rotation is not a 'stand-alone' topic. It should be integrated with other ecological and organic practices for true sustainability. To help you find your way around, there are some useful links for further reading below, but you can also subscribe to our Free email newsletter - The Food Gardener.

Crop rotation is an essential skill for vegetable gardeners

Further reading and useful links