clover as a living mulch: how does it work?

Or maybe, is the way I'm doing it how it doesn't work?

I'm a very beginning permie and semi-beginning veggie gardener. This spring I inherited a rectangular bed in a community garden from someone who's leaving. Last fall she sowed it with (white? and I think a little red) clover. This spring when she passed the bed on to me the whole thing was covered in clover. She said I could plant starts and seeds right into the clover and referenced Masanobu Fukuoka.

So I've been doing that and things are just getting buried in clover. Basil's pale and straggly, lettuce isn't growing, a whole tomato plant disappeared, none of the seeds have sprouted... I spent a lot of time today chopping and dropping to give the poor little starts some room to breathe.

I also refreshed my memory about Fukuoka's methods and it sounded to me like he planted his seeds along with the clover seeds. So I guess the crops' roots didn't have to try to establish themselves amongst a bunch of clover roots that already had a huge headstart.

Anyway, I'm seeking advice. Keep doing what I'm doing? Something else? What do I do before snowfall in fall (zone 6, Pacific Northwest of USA)? Is clover an annual or perennial? Any other thoughts you have about it?

(Side thought: I'm eventually wanting to have the bed mostly planted in perennials. Right now there's rhubarb and a few culinary herbs, I added a couple blueberry varieties, agastache, another edible flower I can't remember the name of, and ground cherry. There's not much space left but I'd love to add perennial greens of some kind - or other good stuff. Suggestions?)

Thank you so much!

Greetings Anna!

Congratulations on receiving a bed to take care of in your community garden! I live in Texas; so there is not much advice I can give on your climate and situation, but here are a few of your questions that I can answer.

Clover, according to Wikipedia, can be an annual, biennial, or perennial depending on the species. For red and white clover, Wikipedia states they are perennials. Since clover is a nitrogen fixing plant, I would advise keeping at least some of the clover in your bed so that fertilizers become unnecessary.

If you know where you would like to plant some other crops, you could try placing black plastic or cloth on top of sections of the clover to shade them out and give your desired plants a head-start. This method is typically used for grasses, but it might work for clover, too. I like that you are chopping and dropping the clover, that will provide nutritious organic matter to your plants. You could also try placing mulch on top of parts of the clover to shade it out. That way when the clover dies off underneath the mulch, the gases released from decomposition will be stored inside the mulch and be ready for the next plants' roots to absorb when the mulch decomposes.

Here are some perennials that I can list off the top of my head for you:

Jerusalem Artichoke (Sunchoke/fartichoke)

Comfrey (great plant for providing phosphorus in your soil- one of the main limiting factors of plant growth)

Asparagus

Since the three macronutrients for plant growth are nitrogen, phosphorus, and potassium, I would advise keeping at least one or more dynamic accumulator of each one in your garden so that you will not even consider fertilizers.

Good luck with garden! If you wait a little longer, I am sure some more experienced permies will be online to answer the rest of your questions.

I took to planting starts amongst existing clover, with little cardboard mulch mats around them to give them some room (and it kills the clover underneath- which should release the nitrogen). Its really fiddly, but it enabled things to actually grow! And slugs live under the mulch mats but don't seem to eat my starts, whereas before they were just hiding in the clover to pop out and eat everything else I planted.

If you planted the lettuce in may, then are going to bolt really quick and look sickly, even if it was in pristine "bare" soil.
If your tomato plant is suppose to be 2ft at maturity you are going to have to clear away 2ft of clover and plant in that bare "hole".
Another good idea is to do both a "GREEN" living clover mulch and a "BROWN" wood chip mulch inch thick.

Thanks for your replies, all. So it seems like planting straight into living clover without suppressing the clover in some way is maybe not the way to go, but a green mulch with a brown chip mulch on top might be - meaning that the clover isn't there to grow alongside the plants, happily sucking up nutrients and competing with the veggies, but rather is there to slowly die/decompose/release nitrogen underneath the chips.

That makes a little more sense to me. I think we've got some chips lying around...

Rather than planting comfrey into the bed (the Grounds guy here is not happy with how much it's spreading all over the property) would chopping 'n' dropping and/or watering with comfrey tea accomplish more or less the same thing (i.e. the addition of phosphorus)?

What plants accumulate potassium?

One thing I'm noticing in my fledgling study of permaculture is that the more answers I get, the more questions I have...

Comfrey leaves make great cover, use them like you would newspaper or cardboard.

As I understand it clover is a fairly vigorous perennial. To plant seeds or young transplants through it you need to give it a fairly substantial knock back. Not necessarily killing it, but suppressing it to the point where your crop species have a chance to get established. I would say that planning to chop-n-drop mulch it, then add a layer of additional mulch material (woodchips, grass clippings, cardboard etc...) would be a good way forward.

Ultimately you probably do want the clover to survive and continue to fix nitrogen for you, you just need to temporarily tip the balance in the favour of your new plants.

And what is the story w/nitrogen fixers? is the nitrogen they fix only available to other plants if the nitrogen-fixer dies?

I'm really impressed by this forum and how many people are taking the time to share their expertise. Thanks, all!

It does not quite work like that. A nitrogen fixer does not have to die to share the nitrogen with other plants. Most nitrogen fixers attract the nitrogen-fixing bacteria to their roots, and then, nodules on the roots with the helpful bacteria form. The plant itself does not do the nitrogen fixing; it is the bacteria that the plants attract and take care of that do this for you. Water, just plain water, is enough to share nitrogen with other plants. Here is a link to article by GardeningKnowHow that explains how nitrogen-fixing plants work in more detail: http://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/nitrogen-nodules-and-nitrogen-fixing-plants.htm

Water is an agent of leaching which means that it picks up and carries nutrients and minerals away which is when soil type becomes very important. Sand, silt, and clay (the three main components of most soils) each have unique properties in respect to their ability to retain water and nutrients. Sand, being the biggest of the three particles) does not hold onto water or nutrients very well. Silt is the middle of the three and its properties are in between sand and clay; it clings more to water, but it is more willing to let plants use the nutrients attached to itself than clay is. Clay is the smallest of the three and it loves to hold onto to water and nutrients so much that the nutrients are no longer available for plant use. As a result, the best soil types are loamy soils because they synthesize the silt, clay, and sand in equal proportions.

@Dave, thanks for the article link. It did say this, though: "While they are growing, they release very little nitrogen into the soil, but when they are done growing and they die, their decomposition release the stored nitrogen and increases the total nitrogen in soil. Their death makes nitrogen for plants available later on." So do the plants in proximity to the nitrogen fixers have some access to the nitrogen without having to kill the nitrogen fixing plant? I'm mainly thinking about the future when I start my food forest -- I mean, people plant large nitrogen fixing trees and don't necessarily chop n drop them, and they're supposed to be beneficial alive, right?

And thanks for the info about the sand-silt-clay ratio of soil. I did not know that.

Anna, the nitrogen fixers share some while they live, and release pretty much all when they die. But, when you chop and drop, the nitrogen in the leaves becomes available as the leaves decompose, plus the living plant prunes it's root system in response to the trimming up top, and those dying roots release their nitrogen.

So chop and drop on plants that will grow back vigorously becomes a really productive method for getting nitrogen into your soil.

That totally makes sense. Thanks for that explanation, Peter.

Today as I was putting brown mulch (cottonwood chips) on top of the clover, the woman who originally planted the clover and let me have use of the bed was walking by and said, "You know adding wood chips to the soil makes it more acidic, right?" And I thought, hmmm... but all these awesome folks on permies.com thought it would be a good idea... Any thoughts on this? When I have more time I'll check out the mulch forum too for info.

Whether the wood chips will change the ph, and in which direction, I don't know for sure. Certainly pine needles will shift it toward the acid, but whether pine chips would also, and whether other wood species do or do not..I would be interested in the answers.

That aside, it isn't necessarily a bad thing, depending on what you are growing and where your soil ph started out.

I know this probably is not helpful, but if you are interested in testing out some the questions you have asked, you could setup an experiment and post the results on permies.com.

A few supplies for testing pH and NPK:
-litmus paper
-a soil testing kit

These usually aren't very hard to find.

What I remember form reading his book was that he flooded the field for (i dont remember how long) before sowing rice. This weakened the clover enough to get the rice established.

Well, clover isn't enough, mixed living mulches are better. But here is a great playlist on living mulches. Permaculture living mulch