Crop rotation and permaculture

Hi all,

most books on permaculture do not even mention crop rotation (in the sense of not planting annauls of the same family on the same bed for a couple of years).

Some practices - like not even having divided beds/blocks but instead just putting plants where a gap appears - seem to make crop rotation virtually impossible.

Permaculture is about observation, and I observe that many gardeneres in the mediterrean plant their winter brassicas in the same beds every year,
on the other hand farmers have developed crop rotation based on observation/insights obtained by several generations,
and those conclusions made it into the conventional gardening/farming books.

When asking other permaculture people IRL about crop rotation, they say that they don't really care about it.
They also bring up examples where people have been successfully ingoring crop rotation rules for decades,
because everything will be fine if you put enough compost on the beds every season.
While this argument seems feasable for nutrients, it is the diseases that are concerning me.

Let me elobarotae with the example of Clubroot( Plasmodiophora brassicae ). If someone plants brassicas on the same spot for 2 decades
and finds his plants free of  Clubroot, i cannot take this as a proof that you can plant brassicas in this way without risking loosing your crop and infesting the soil with clubroot.
My argument is, that if there is no clubroot spores, it will not manifest out of nowhere, no matter what you do.
So if someone wanted to prove to me that just by using sufficent compost you can circumvent the clubroot problem,
he would need to inoculate the soil with clubroot and keep growing.

Now my question is, has anyone ever done such an expermient?

My focus/issues with crop rotation centers around brassicas because they seem to be the staple annual vegetable in the temperate climate
especially during the colder season  (Don't forget Turnips are brassicas , they used to fill the niche potatoes took over) and most of the profitable market gardet crops are brassicas too (Asia salad, arugula, radishes just to name a few).

The only cost that I have incurred in order to do crop rotation is the time it takes to plan it o
I too have not felt convinced that crop rotation is not needed. I worry sitting in one spot might breed conditions to allow unfavorable outcomes when it comes to disease.

Arguments that I heard is that if you have a polyculture then you don't have to worry about crop rotation. The argument is the soil food web interacting with the plants is some kind of 'immune system' compared to monoculture crops? I'm not sure what that mechanism is.

I'll be curious to see some answers!

There may not be a lot of discussion on crop rotation because there is more talk about planting perennial vegetables and planting polycultures.

I am a believer in practicing methods for soil health so I feel crop rotation of annual plants might be necessary depending on the plants.

Maybe some plants use more of the nutrients than others making it a necessity to rotate to something else the next years.

And as Timothy suggests with polyculture this may not be a necessity.

It is a question of balance. With the right combination of living, the right connections, a rich soil, anything you call a plague is an element of the system in imbalance.
The imbalances can be solved killing that which is in excess o adding that which is in default. But it is better and more of a long term solution if it can be solved creating the conditions that discourages that which is in excess and promotes that which is in default.
In what conditions does the clubroot prosper? How can these conditions be prevented? What outcompetes it? How can it be promoted?

Nature hates repeating itself, so growing the same stuff in the same place over and over again will find Nature's oposition. That's why sometimes we neet to fallow. Evolution is dynamic; if your work is static, it will stay behind. Crop rotation is just another method for staying ahead, not the only one.

Abraham Palma wrote:
In what conditions does the clubroot prosper? How can these conditions be prevented? What outcompetes it? How can it be promoted?

I tried some research on that topic, the only thing i found is that acidic soild favours clubroot, whereas alkaline soil somewhat inhibits it.
Also warm wheather favours the patogen, so one should plant them as overwintering crops rather than summer crops.
(makes sense anyway, because there are so many other things to grow during summer, while winter veggies are almost excusively brassicas)

Also there are some brassica cultivars (conventially bred, not GMO) that have resistence agaist clubroot, however the intensive usage of those resisent cultivars on clubroot infested land led to the emergence of new clubroot strains that can infect the resistent cultivars.

Excellent!
Do you know if garlic/onions have any effect on them?

Most of permaculture seems to focus on perennial plants.

It helps to think about why we rotate annuals.  Soil nutrients (build better soil), pests (companion planting), and illness (mostly companion planting and saving our own seeds so we don't need to bring in plants or organic matter from off site).

I found, if we observe carefully, I seldom need to rotate crops unless one of the three pressures mentioned above gets too much.  Then again, most of it is solved by running the chickens in that area for a winter.

I found this thread today on a break from building mounds for a three sisters garden.  As I was digging up soil to make the mounds I was thinking "This sure is a lot of work, I dunno if want to do this every year as I rotate through my garden!"

I think where it's easy to rotate crops then why not? But if you need to make special infrastructure  like mounds or supports for vining plants etc then don't bother and research landrace cropping and seed saving to evolve past any local pathogens.

just my 2 cents and for what's it's worth I'm no master gardner😀

My gut feeling is that the closer we garden in monocultures the more important rotation is. I don't think there is much down side - special preparation for specific crops as Jeff suggests can actually be useful: nutrients can be concentrated for those crops that appreciate it more (like wood ash or manures for brassica and potatoes).
I like to have a rotattion going in my polytunnel because it is not a natural environment. The enclosed shelter means that pests and diseases can be protected from natural predators and system balance is more difficult to achieve. I'm hoping that by rotating my tomatoes around the area I will be less likely to have root diseases, but maybe I'm fooling myself!

I don't ever plant the same thing in the same spot each year for annuals.  I guess the exception is self-seeding annuals who plant themselves before I can do something about it haha.

Something like potatoes, I'm extra careful about because the blight lives large in my mind.

Riona Abhainn wrote:Something like potatoes, I'm extra careful about because the blight lives large in my mind.

I always think blight is more weather dependant - not much you can do with planting, although covering the plants when you get blight weather might help (like with tomatoes). There are other soil bourne pests/diseases of potatoes though, so it won't hurt to rotate them.

Rotation breaks disease cycles, BUT… it also breaks mycorrhizae and other beneficial cycles. Which is a bigger threat or benefit depends on your situation.

Monoculture became a necessary convenience for agriculture.  Some large ag farmers are going away from it, sort of. They are stagger planting or skip-row plant cover crops or companion crops to get diversity but enough difference in maturity by timing to still mechanically harvest at least the main cash crop.

The mycorrhizae point is worth taking seriously. Rotation breaks disease cycles but it also disrupts the fungal networks that build up around specific plants over time. In a polyculture with good soil biology you probably get enough natural suppression that strict rotation matters less. But in a polytunnel or any enclosed space I'd still rotate, the conditions are just too controlled for the soil food web to compensate on its own.

My experience is:

- I can can rotate without deep tilling.  

- Mycorrhizae seem resilient enough to recover from mild disturbances.  

- I suspect rotation is mostly to change/support different soil biomes that enable different minerals to become bioavailable to the plants.

I think diseases are usually secondary.  Meaning they tend to be a side effect of conditions-stressors (too much or too little sun, wind, water; too much nitrogen; or lack of compatible plant/fungi communities) and/or lack of needed nutrient availability (typically, lack of compatible plant/fungi/biome interactions).  I've come to this conclusion after years of growing and having people note "How is it your X doesn't have X (bug, disease, problem, etc)??"  I grow a garden in a radically different way than most people.  It's the whole system in action.

- Much of my rotation happens naturally on it's own.  A large part of my annuals and biennials are self seeding and move all over.  They only require a tiny amount of soil disturbance, like literally scratching the surface.  I don't usually even do it myself.  I think birds do.  Carrots, celery, parsley, Sweet Williams, hollyhocks, lemon bee balm, cornflower, Hopi tea - these all move around the garden at will.

- Nitrogen is not a fix-all.  I've found it's use causes nearly as much problems as it seems to fix. Example, Strawberries can last a long time in one spot if they are being grown in a diverse enough low nitrogen system.  I suspect overfertilization causes them to crowd themselves badly, and then fizzle out.  So the need to rotate increases, or the soil is perceived to get "tired".  

That's my sense of these things at least.  I have lived and grown plants in the PNW and the desert SW.  But I have no experience in the east, mind you! So I can only speak to the western growing conditions.  :-D

To me crop rotation is important if you plant a lot of one thing in one place, and not really import if your crops are already interplanted.

Of course if theres a disease or pest in one area you might choose to plant elsewhere, but you’re less likely to have fungal or virus or even pest issues if you don’t plant all your potatoes in one big block, and they’re instead spread out with other types of plants between them.

I just started reading "Gardening When it Counts" by Steve Soloman.
It has some very astute observations, like plant spacing to not need water (once the seedling sets off) which is kind of obvious but not what the lots of compost and squeeze as much in as possible brigade always suggest.
Anyhow, for a family garden he suggests having two areas, leaving one fallow for three years while only using the other. Plus feeding his design of universal compost.
So crop rotation from a wider perspective.

problem with the fallow approach is you have no hope of ever controlling  weeds.  One approach I want to pursue once I have chickens next year is the 'dueling gardens' technique.  Keep chickens where last years garden was and where it will be again next year.

Jeff Marchand wrote:problem with the fallow approach is you have no hope of ever controlling  weeds.  One approach I want to pursue once I have chickens next year is the 'dueling gardens' technique.  Keep chickens where last years garden was and where it will be again next year.

If you've spent three years controlling the weeds where you are growing, then put that to "fallow" maybe seeding clover at the start, you still think weeds would go nuts?

Hello,

I also think it depends on your conditions. For me it is slug pressure under heavy but very short rainfall.
Departing from an unproductive (for my little stomach) mixed polyculture, I planned a rotation in the veggie garden this year, with potatoes - pulses - leafy green - roots.

There is still a perennial structure in the form of ash, redbuds and pear trees that are scattered in the garden, feral parsnips and chards that grow wherever they please, and the drip lines running just under the surface and used once a week. The paths are covered in wood chips and full of wild mushrooms.

Still I have to feed my growing soil with mulch, compost and hay, and on the other hand litter-covered soil is a shelter for slugs and snails that were able to destroy nearly everything I planted until now.

So I concentrated all the mulch of the year in the potato part, and the remaining surface is only protected with goutweed between veggies. I plan to rotate this every year.

So far, we have had our usual spring drought and peas, goutweed, chards and celeries have been quite good ; storms came in last week as forecast and the slug pressure has been much lighter than usual in the veggie garden.
I am facing the summer with exploding greenery and around 9 weeks worth of water in the tank.

We'll see ...