Crops Need Rotating Say The Gardening Experts. But Is Crop Rotation Necessary? In Farming Crop Rotation Goes Back Centuries But Conditions Were Different Then. Here’s My Experience Of Rotating Garden Crops.
I think people don’t always understand what rotation means and that they also confuse agricultural rotations with gardening rotations. So does Crop Rotation in the garden make sense? Do we need to rotate crops every year or can we grow the same crops in the same soil year after year?
What Is Crop Rotation?
Part of the confusion about crop rotations is the definition. To me it has TWO meanings. It’s both about the annual rotation of crops in a given year and the rotation between or over the years.
Let me explain a bit more. In any one year, as a commercial grower, I’d grow more than one crop on a given area of land. I might start with planting lettuce in March, harvest them in June and immediately plant leeks. That way I had a lettuce and leek rotation within the same year.
Next year I might do exactly the same thing and arguably that means I’ve grown lettuce on the same land two years in a row .. ditto, leeks for two years. Many people would therefore argue that I have not rotated my crops properly and am growing the same thing in successive years.
Of course the type of veg I’m growing might vary but the principle will be the same. I’ll be growing the same crop(s) every year. But it really doesn’t matter. If it did then arguably the Amazon and prairies would have died out years ago. And ancient woodland would never exist, because they are growing the same crops for centuries! The are many woods growing just one species, eg oak, beech, Scots pine, etc so the argument sometimes given that woods are a diverse mix of species doesn’t always bear scrutiny.
I used to grow commercial vegetable crops and frequently grew the same crop on the same land year after year. BUT that’s not the same as saying I didn’t rotate. Though I may have grown onions for ten years on the same spot I was also able to grow peas in the same year (rotation) to add back nitrogen.
Farmers often grow one crop a year. For example, maybe they’ll grow cereals year after year in the same fields. That’s then called monoculture and frowned upon by some people.
But, as explained above, in market gardens and gardens we frequently grow more than one crop a year on a single piece of land. Another example would be where I’d grow lettuce followed by a second lettuce crop and then put in peas, all in the same year. Or celery followed by lettuce and then broad beans. Or I’d do lettuce followed by radish followed by leeks or cabbage.
There are loads of variations but each plot grew at least three crops a year. And in many of these variations it meant I grew the same species on the same plot year after.
What this really means is that you can both rotate various crops over the year and still grow the same species on that land at the same time.
In green houses I could get three to five crops a year with no rotation problems. Sometimes that would be five crops of lettuce in a single year. Sometimes it would be several different species in the same year.
Why Is Rotation Recommended?
If we go back to mediaeval times growing was different. Farmers and gardeners didn’t have the understanding we have today. If they grew the same crops in a field for years they eventually had pest or disease problems and the crops failed. And if they kept growing crops without adding nutrients back into the soil then the soil became depleted and crops didn’t prosper. Today we know that if we remove organic matter in the form of fruit and veg we need to replace it with compost or fertilisers. So we no longer have depleted soils.
In the past rotations made sense. And when “Turnip” Townsend adopted the Norfolk Four Course Rotation, on his lands at Raynham in Norfolk, it made sense to grow a rotation of turnips, barley, clover, and wheat crops. This was for agriculture but somehow we seem to have transferred the concept to gardening where it doesn’t quite fit the circumstances.
Are There Now Reasons To Rotate?
Yes. But the only time I’d suggest you purposely do so is when there’s been a bad disease or pest problem that will carry over from crop to crop. That’s actually quite rare. Otherwise there is no reason to do so.
Charles Dowding has been trialing the same crops, eg potatoes, on the same beds for years. He records no adverse issues.