The Law of the Limiting Factor
In this unit, I’m going to share a forgotten natural law that food gardeners all over the world are using to grow bigger and better backyard crops.
When you apply the gist of this law to your food garden you’ll be able to harvest loads of crispy fresh vegetables… armfuls of aromatic herbs… and baskets of sweet fruits… all from your own backyard, patio or balcony.
Are you ready?…
I’m going to spare you the history here, but I’ve included two links at the end of the lesson. So if history interests you just follow those links.

What’s important here is that Liebig’s Law of the Minimum often referred to as Liebig’s Barrel, holds the secret to having a bountiful harvest of any crop you can think of.
This law states that the growth of your plants is not controlled by the total amount of nutrients available but by the scarcest nutrient – the limiting factor.
It’s worth reading that again… the growth of your plants is not controlled by the total amount of nutrients available but by the scarcest nutrient – the limiting factor.
Does that make sense to you?
Now here’s the twist…
The fertility of your soil, in other words, the amount of nutrients in your soil is just 1 of 15 factors that can limit the growth of your plants; and ultimately the size and quality of your harvest.
What’s more, if we rank these fifteen factors in order of importance soil fertility only ranks at number 10 out of 15. There are nine other factors that have a bigger impact on the health of your crops. To be successful you must first remove these limiting factors.
We can group these limiting factors into five groups. Let’s quickly review them in order of importance.

Note: Registered participants can download a detailed mind map below.
First up there’s you … the gardener
And you bring three of the most important limiting factors to your food garden.
The most important as a limiting factor is your gardening system. A system is a proven set of gardening activities that Saves You Stress Time Energy and Money. It’s something that continually evolves with your knowledge and experience. And it is absolutely critical to your success as a food gardener.
Then comes your skills, knowledge and experience; and then your resources such as gardening space, time, energy and money.
The next category is the seeds and plants you plant in your food garden. How they match your skills and gardening system; and their origin. In some conditions, heirloom seeds may be best. In others, hybrids will do better.
Next is your climate which determines the length of your growing seasons. The critical limiting factors are your average minimum and maximum temperatures, the amount of sunlight, your average rainfall and the prevailing winds. Most of these can be adapted to some extent with growing structures.
The fourth is your soil. The first limiting factor in this group is soil fertility. This is the quality and quantity of nutrients available to the soil life and to your plants. And it is worth noting that the quality of the nutrients is more important than the quantity.
Then comes soil biodiversity… in other words how alive your soil is. And then we have soil structure. Whether it is clay, loam, or sandy soil.
The last group of limiting factors is natural competition. It includes pest, disease, and weeds in that order. This group is where most food gardeners struggle and where they usually focus a lot of energy and resources. But this is the wrong end to start.
The fact is if you remove, or limit, the preceding four groups of twelve limiting factors pests, diseases and weeds won’t even bother you.
Let’s recap Liebig’s Barrel or the centuries-old natural law that can help you grow bigger and better herbs, veggies and fruits if you apply it with a modern twist.
The growth of your plants is not controlled by the total amount of nutrients available but by the scarcest nutrient – the limiting factor.
To be successful you must remove the limiting factors. And the most important limiting factors are the growing system you are using, and your skill in using the system.
The great news is that implementing a food gardening system is not rocket science. And in this course, you’ll get the framework of a proven food gardening system that any food gardener, irrespective of their skill level, can use to remove all the limiting factors one by one.
I am very curious to try these methods.
Makes sense.
Thank you, this is very useful.
An actual.system would be fantastic
I realize how little I know, I cant wait to try this in my veggie garden.
The SYSTEM acronym is applicable to so many areas. And I do agree that my growing system and skill level may be very limiting to my plants.
Can’t wait to start gardening and growing herbs
Quite interesting. I now realize that I am a complete novice gardener and that there is so much scope for improvement.
My current limiting factor is learning the ins and outs of a new gardening zone after 20yrs in a much different zone. I’m sure it’s going to take a few seasons to be comfortable with it, and then maybe a few more to be as successful as I was in my previous zone.
It surely looks as if I’ve been gardening the wrong way around… Three huray’s for Liebig’s Barrel.
For pots I mix my own soil, I have a sement mixer for this. For the garden, I do what is called trenching and mix in all my nutrients then put the soil back. Time and a strong back if you do the work yourself is what you need. Time, I would say is the most limiting factor to a successful system. Time is split in to many things, like getting your nutrients, preparing the bed, tilling, aerating and mixing in nutrients, allowing the soil to settle, seed germination, transplanting (especially in SA with the hot sun the seedlings need hats), mulching etc. Time is the most limiting factor to a successful garden.
Last season I got attacked by every pest under the sun. Snails. Slugs. White cabbage flies. Caterpillars. Rats. Mice. Possums. Cockatoos.I’m looking forward to learning how to win this war.
Interesting and useful.
I definitely need this particular class!!
I need a good system in my garden. I’m looking forward to learning more.
This is really interesting. I can’t wait to learn more
We love our garden, this will help.
I did not know the limited factor, this is good information to know. Thank you.
Very intriging
I never know what soil to use when planting my herbs. Which ones are the best
This is very very interesting and I’d like to try it.
Liebig’s barrel theory is crucial to successful gardening. It is good to know that the Gardener himself is a major contributor to the growth nourishment and success, good quality and quantity yields of his Garden. He or she must remove the limiting factors like his growing system and skills in using the system. So good to know.
I did not know the limiting factors included the Gardner as well. Thanks for the info
I would like to try this and see how it goes
https://youtu.be/6gm6Yq7uNBw I believe the Zimbabwean farmers were responsible for this and it has been more successful than anything else
Makes a lot of sense.
My husband has a system of making enriched biochar which transforms the soil.
Wow what an interesting course this is. Thanks a lot for breaking down the information in such an interesting way.
To me, the bottom line is to make sure I remove all the limiting factors and I will be a successful vegetable and herb gardener. I’m exited to put the Liebig’s theory in place.
This is really a easy-to-use system. Love it
Liebig’s barrel theory makes so much sense to me; in essence he is saying that if I remove the limiting factors, I should be successful as a vegetable and herb gardener! I am really excited to start my garden and put Liebig’s theory into practice.
This course is super, I’ve learned so much. Thank you
This makes sense. Thank you!
The light bulb has gone on! Very clear and easy to follow! Thank you!
The light bulb has gone on! Very clear, thank you!
I knew most of what is said in this unit, but never have I seen it put together, or laid out so well before. It is like a puzzle coming together for the first time.
Wow! So much information to digest. It just makes good sense that the more you learn and put into practice the better your success will be. Finding a solution to your limiting factor, I feel, is the key.
Thank you….I have learned much!!
Soil fertility is 1/15 factors for the Health of your crops…..I understand now x
The Law of the Limiting Factor makes sense to me and I believe if you don’t have a passion for growing your own crops you
will not be able to make a success of it.
Which seeds are the best to start with?
Hi Di-Di. May I give you all the info on my setup so you can see what I’m doing wrong or if it is a stupid idea.
Hi Cathy. I don’t know if you’ve enrolled in the Beginners Edition of the How To Grow Bigger and Better Backyards Crops Course. If you did, jump to the Food Gardening Skills Assessment, it will give you a pretty good idea of what you are doing wrong, and where to focus your attention.
Good morning! I have recently discovered that the topsoil of our plot was sold when the plots were measured out about 20 years ago. What’s left is orange, and sandy/stony. Are there ways that we can build back, or will we have to buy topsoil?
Hi Dorothy. That really makes one angry. Anyway, in the short term you can build back with a combination of good compost and manure. On the long term add green manures and patience. Also, don’t plant crops with a high nutrient demand for the first year or so. Best of luck.