Planting in a Post-Wild World


The front lines of the battle for nature are not in the Amazon rain forest or the Alaskan wilderness; the front lines are our backyards, medians, parking lots, and elementary schools…This book is dedicated to anyone who can influence as small patch of land.

—From the introduction

Planting in a Post-Wild World: Designing Plant Communities for Resilient Landscapes, by co-authors Thomas Rainer and Claudia West, is a beautifully written and illustrated guide to how we should be designing our landscapes from now on out. Simple as that.

Thank heavens someone has finally written this book.

It feels to me as if this book is not just another entry in the overcrowded gardening category, but a manifestation of a something needed, something important, something that’s been waiting to come into the world for a long while.

I know, I’m getting a little woo on you, but I’m excited.

I’m excited because this book unites philosophy and practice. I’ve written many times on this blog of the need for what I call “loving landscapes” — diverse, sustainable gardens which serve the greater good. And I’m not alone. After the long tyranny of the lawn and hedge, there’s a revolution underway. The problem is that for all of our good intentions–us lawn remover types–we don’t necessarily know how to replace the dominant paradigm with something both attractive and sustainable. We have precious few good models to follow. And for all our good intentions, sometimes our efforts fail.

Now we have a guide.

The basic premise of this book is that the traditional approach to garden design, which is based on arranging individual plants in a landscape according to abstract, anthropocentric principles, such a color harmony, creates lifeless, high maintenance landscapes.

You end up with beds of annuals that need constant upkeep, lawns which need mowing and chemical CPR, and sad perennials floating like lonely islands in barren seas of mulch. These gardens may look tidy (and somehow tidy has become perhaps the single most important virtue in landscape design) but they are a lot of work to maintain, and they don’t do much other species, or the air, or the soil, or the water… and they don’t speak to our souls.

Rainer and West ask us to go out and look at places where plants grow freely. This might be in a place we call “nature” — a local wildlife preserve, perhaps– or it might be in a vacant lot in your neighborhood. Left on their own, plants form dense, cooperative communities. These communities are generous and life-sustaining on many levels. The authors ask you to consider how you might be able to mimic these local communities to create landscapes which are more sustainable all around, landscapes which can delight our eyes, and heal the land.

The underlying philosophy is that while the natural world is enduring terrible losses everywhere–losses we can do little as individuals to prevent–we can support nature in our own backyards and office parks and school gardens. Our world is post-wild, but that does not mean it need be lifeless, or sterile, or stripped of all relationship and love. The post-wild landscape is a new paradigm for plant-human interaction.

Translated, this means making more diverse, untrammeled landscapes. Perhaps best known example of this is the High Line Garden in New York City. Did you know the High Line has become one of the most popular tourist attractions in the world? People love this garden. The naturalism of the plantings speaks to them, I think, as does the attractive interplay of built and wild.

High Line Garden in NYC

The High Line. Photo credit: bettyx1138

As the High Line’s designers know, the trick with this kind of landscaping is letting it be spontaneous, but not too wild, so the neighbors don’t call the authorities and accuse you of growing a yard full of weeds.

There are strategies for getting around this, and Rainer and West cover this well. For instance, part of good design includes providing what they call “frames” (also called “clues to care”) which are basically man-made elements which neaten the wilder spaces, making the viewer understand that this is a cared-for space.


Pic from the book. An unidentified rooftop garden showing good use of “frames”: design elements which make spontaneity palatable.  I want to live there.

But the real challenge in this process is designing a plant community which is attractive and functions in a sustainable, self-supporting way. These landscapes are not completely care-free, but if designed correctly, they should require less in terms of human intervention that traditional gardens. A beautiful wild meadow doesn’t need our water and weed killer, after all, and we have to ask just why that is.

We can’t hope to match Nature in her complexity and wisdom, but we can mimic her ways as best we can. So this is not just a matter of letting your existing plantings run wild. This is a well-thought out and carefully executed design process. Rainer and West do a fantastic job of breaking the task down into clear steps. (If you’re a fan of Piet Oudolf, you might call this Piet for Dummies–all apologies to the authors.)

They cover more ideas than I can even touch on here, including, importantly, a fine stress on recreating a sense of the local and the specific in your designs. I could spend the rest of the year talking about just one idea from this book at a time–but I’m not going to. I think you should just buy it and start planning.

But one of the most innovative practices they stress is designing in vertical layers. Plants are not arranged as individuals, but in dense inter-layered communities, with allowances made for various factors like root depth, function, behavior and seasonal succession. Under this model, no ground is left bare for weeds to colonize. There’s no need for mulch either, as the community forms its own green mulch. Every planting has four vertical layers: the structural layer, the seasonal theme layer, the ground cover layer, and the filler layer. Plants stacked on top of plants. Plants intertwining. Plants giving way to other plants as the seasons progress.


Another pic from the book showing the system of vertical layering in the design process.

They give concrete examples for how this would work in three different types of archetypal plant communities: open grassland or meadow, woodlands/shrublands, and open forest. These three community types relate surprisingly well to most landscaping needs. The grassland applies to flat open spaces with no tall species present. Woodland/shrubland relates to the typical suburban yard where trees and shrubs mix with lawn. The forest is for those lucky enough to have land with stands of trees.

Planting in Post-Wild World is not a simple how-to book. In fact, there’s nothing simple about it at all– but it is very clear. Its goals are ambitious, and while it might seem like it was written for designers, it can be used by a determined home gardener. It has to be, I think, because there aren’t that many designers out there working this way yet. And while I firmly believe in the value of investing in professional advice, we can’t all afford it. Basically, we all need to be designers now, because the need is great and the stakes are high.

So some of the vocabulary may be confusing at first if you’re new to this, but that is what the Internet is for (not for sharing cat videos, despite all evidence to the contrary). If you’re willing to sit down with the book for a while and do the research and thinking it asks you to do, I believe you could come up with a beautiful, resilient landscape of your own.

I have to believe this because I’m in the midst of doing it myself. I’m using this book to redesign our front yard.  I’d been trying to figure out a new design on my own–struggling in my half-baked, improvisational way to create a more loving landscape out of the Grey Gardens situation we’ve got going now — and not making much progress. Then this book came to my rescue.*

Look for posts in the near future charting the progress of our redesign using this system. October/November is the time for this work in Southern California. The idea is to get the plants in before the winter rains, so they can establish before the summer heat and drought hits.

In temperate climates, folks are just beginning to put their gardens to bed for the winter. So you lucky people can just curl up by the fire and sip your hot cider and read this book while the rain and snow falls outside your window. Meanwhile, I’ll be outside, chopping and hauling and digging and planting in the ever-bright LA sun. If you follow along, you should get a good preview of the process before spring rolls around.

*Disclosure time: I asked the publishers for a review copy of this book, because Erik and I are familiar with Thomas Rainer’s good work–and they kindly gave one to me. Score! But seriously, I’d pay good money for it, and the fact that I got it for free did not create the enthusiasm you’re seeing here.

A Neoclassical Native Bee House

beehouse closeup best

Inspired by the LA Natural History Museum’s bee houses on poles, I dashed off my own version in Sketchup. It’s an homage to Ian Hamilton Finlay.

beehouse long shot best

Kelly is supportive but skeptical. I’m hoping it can be a part of the reboot of our front yard, which we’re about to embark on. The plan is to remove unsuccessful plants and make the space more welcoming to wildlife. More on that in later posts.

Ian Hamilton Finlay’s Gardening Wisdom


Photo of Ian Hamliton Finlay at Little Sparta by Murdo Macleod.

Recent developments in our front yard landscape that will go unmentioned led to an evening of reviewing the works of my favorite poet, gardener and artist, the late Ian Hamilton Finlay. I thought I’d intersperse excerpts from his prose poem Unconnected Sentences on Gardening with a few of my disjointed reactions,

A garden is not an object but a process.

I need this sentence tattooed on my forearm as I tend to want the garden to be “finished”. A garden is never finished, never complete, never the same. A garden is like the ever unfolding novelty of the divine logos; it’s never static; it’s always in motion. As Heraclitis says, “You cannot step twice into the same river; for other waters are continually flowing in.”

Installing is the hard toil of garden making, placing is its pleasure.

I think I’ve spent too much time in the installing and not enough time contemplating the placing. In so doing gardening has become more of a chore than a pleasure.

Superior gardens are composed of Glooms and Solitudes and not of plants and trees.

I take this to mean that a garden should express moods and ideas and not be just a collection of plants or a collection of objects set amidst plants. Finlay’s garden is a poem. While it has a lot of sculpture in it, it’s not what you would call a “sculpture garden” which Finlay speaks despairingly of as little more than an “outdoor art gallery.”

A liberal’s compost heap is his castle.

Garden centres must become the Jacobin Clubs of the new Revolution.

Certain gardens are described as retreats when they are really attacks.

Finlay’s garden became a literal battle ground for his disputes with the Scottish Arts Council and with local town council bureaucrats. At various times his art was seized by the police and he became embroiled in a tax dispute with local officials. In the early 1980s his friends, dubbed the “Saint-Just Vigilantes” after the French revolutionary leader, successfully repelled a raid by the police in an action Finlay dubbed the “First Battle of Little Sparta.” Much of Finlay’s garden serves as a memorial to this personal struggle. But Finlay’s garden (dubbed “Little Sparta” after the conflict) also serves as a broader metaphor for every garden as an act of resistance against injustice, war and the destruction of the natural world.


The murmur of innumerable bills was known to most great gardeners.

No kidding. As Kelly and I ponder the reworking of our front yard (yet again–see garden as process above), I too am pondering a new set of bills. Finlay being a poet could also be punning on the word “bill”. Perhaps he also means “bill” as in laws, taxes and zoning regulations. Either way there’s always an unsettling worldly threat looming outside the peace of the garden. As Poussin’s enigmatic painting Et in Arcadio Ego hints ateven in paradise death, destruction, credit card bills, tax collectors and building inspectors intrude

To see more of Finlays’ work visit the Little Sparta Trust website.

Admitting Gardening Mistakes


The unhealthy factor that I bring to our marital garden design dynamic is a resistance to change and a unwillingness to admit mistakes. Take, for instance, the stone fruit trees in our front yard. The “new normal” that climate change has brought to our region–fewer chill hours and drought–has greatly diminished the health and productivity of most of our stone fruit. It’s time for those trees to go and for the execution of a more coherent and attractive landscape plan. As Hermann von Pückler-Muskau advises in his 1834 book Hints on Landscape Gardening,

I know of nothing more pathetic than when a failed detail is allowed to remain as an eyesore in a completed project, rather than being removed and replaced by a better idea, simply because it has already cost such and such in the first place, and changing it might cost again as much. . . Once changes have been found advisable, though, it is also dangerous to put them off, for whatever is incorrect in the current situation will likely show up again in the execution of the new project.

Gardening requires a ruthlessness and lack of attachment that I often don’t have the stomach for. Sometimes you have to embrace creative destruction and curse that fig tree (or, in our case, curse the diseased and unproductive Nectaplum tree; the fig is doing just fine).

Time to get started . . .

Mulch, mulch, mulch!


I like the color contrast going on here between pinkish fallen avocado leaves and the grey-green foliage of this California Fuchsia

[This is one post in a series of posts on the loving landscape, collected under the tag “Back to the Garden”]

Last week we talked about compost. This week, we touch on a second key to soil health, mulch.  Both compost and mulch foster the life of the soil, and both are important components of the loving landscape. Sometimes they are confused for one another, but they are quite different animals.  Compost, which we talked about last week, is more nutrient rich than mulch. It’s full of life, and inoculates soil with that life.

Mulch, on the other hand, is a blanket for the soil. (A blankie, as I think of it in my more regressive moments.) It is not a living material, as good compost is. Rather, it is made up of dead, dry plant matter (dead leaves, shredded wood, straw, etc.) which is spread to form an insulating layer over the soil. Simple as it is, a mulch layer is vital to the life of the soil. In nature, no one comes around with a rake to tidy up. Plants drop dead matter all the time, and that stuff lays there until it breaks down. That is how it should be. In a loving landscape, we try to replicate the patterns or habits of nature, and one of the most important habits she has is letting stuff fall and lay there.

This, by the way, entirely contrary to common gardening practice, which seems to believe that if a surface isn’t covered in turf or cement, it must be swept as clean as a kitchen floor. I see a lot of dead soil in my neighborhood, dry and exposed and baking in the sun–but ever so tidy.

Insulating the soil provides the conditions necessary for life to bloom in the soil. Mulch helps retain soil moisture (which lessens the frequency of watering) and protects soil life and plant roots from the extremes of hot and cold, and builds new soil over time. It provides habitat for beneficial insects (And yes, some not-so-beneficial ones as well. We’ll talk about that more.) So while it is not as biologically active as compost, it creates the conditions which support life.

Finally, mulch becomes soil. Over time, it slowly breaks down and becomes new soil. If you dig a hole in a yard which has been mulched for a few years, you can see the rich dark soil which appears just beneath the mulch layer, very different from the older soil lower down.


Let me tell you a story. Our friend Kazi recently bought a new house and is in the process of planting gardens in the front and back yards, which had been sorely neglected. In the big back yard she discovered the previous owners had, for reasons known only to themselves, blanketed the soil with big pieces of polyester carpeting and sheets of black plastic. Beneath this stuff, the soil was dry, hard packed and lifeless.

She threw away the plastic and carpet and put down a thick layer of shredded wood mulch. In addition, she ran drip lines beneath the mulch to bring some water into the picture. (That is necessary here, as we get so little rain–it wouldn’t be necessary everywhere.) She let that stew for a couple of months, and then checked back in.

As if by magic, the soil beneath the mulch had come to life. The water and the insulation called to the worms. They came from…somewhere. (The ways of worms are mysterious!) And they went to work opening up the lifeless, compacted soil, changing its texture and color. On a microscopic level, a host of bacteria and fungi had also gone to work in Kazi’s soil, producing nutrients in the soil, readying it for planting.

And all Kazi did was lay down a truckload of mulch, and then retired to her porch for a well deserved cocktail. No tilling. No digging. Nature does the heavy lifting.  This is the wonder of mulch.

Sound too good to be true? The underground, invisible life of the soil, and its relationship to plants is amazing. To learn more, check out the classic text: Teaming with Microbes by Jeff Lowenfels and Wayne Lewis.


Mulch  looks nice–at least to my eyes it does. I admit that I may have eccentric vision. Life is beautiful, and I see in mulched spaces the promise and hope of life. When I walk in our mulched yard, I can imagine I’m in the forest, walking in quiet leaf litter. Meanwhile, when I see vast tracts of green lawn, I think, “What is it feeding?” And the answer is, nothing. Lawn asks for so much in terms of time, labor, water and chemicals, and gives so little back. Whereas mulch costs little, and gives much.

If you decide you won’t have a lawn (or much lawn), mulch is one of the best ways to unify the look of yard and garden, to make it look tended and tidy. Mulch also represses weeds. I think of it–again–as a blanket stretched across a neatly made bed. Mulch is homey and comforting. It also provides a soft, clean surface for walking, and of course, there’s no worry about too much foot traffic!

Dogs, by the way, seem to do just fine on mulch. They don’t, contrary to popular belief, need a lawn. In fact, we all know they are hard on lawns.

As far as kids go, a yard full of trees to climb, secret forts, chickens, flowers, vegetable patches and interesting critters and bugs might better lure them outside than a perfect lawn. I know many happy kids who live in such yards. And as a kid myself, I preferred such spaces. I have no fond memories of grass. I do have strong memories of playing in wilder spaces–under trees, among boulders, in a rainy gutter, in the snow, at the beach. Lawn, for me, was always a suspicious place full of dangerous sprinkler heads and hidden dog poop.

The one exception I will buy for lawn is as a good surface for babies and toddlers. It’s nice to have a clean, soft patch of grass for them to plunk down on when outside. But that doesn’t have to be a big patch to be very useful and fun–and if the rest of the yard is full of life, they’re more likely to be visited by ladybugs and butterflies!


1) From the trees, from the ground:  Think of your yard as a closed system. Nothing leaves.  Leave the Leaves!  Nature doesn’t pack precious plant material up in plastic bags and send it to the dump, and neither should you.

  • Keep all of your fallen leaves. Get your neighbor’s leaves, if you can. Spread them in place, or store them in bags until you need them. Pine needles work, too.
  • Pull weeds before they go to seed and leave them on the ground to dry up and vanish into the mulch layer. I swear, it might look strange to see them laying there at first, all green and bright, but they’ll be pretty much invisible in a few days.
  • Practice “chop n’ drop”. When you’re pruning bushes or trees, chop up softer trimmings to about 6″ (15 cm) and leave them at the base of the plant. The plant will appreciate it. You can leave woody branches here and there, too, to support beetles and other bugs. (I make little piles of fallen wood, hoping to host lizards, but resign myself to the fact I’m more likely hosting mice. Well, it gives the neighbor’s cat something to do!)
  • If you have a lawn, save all your clippings. They make great mulch (and compost). To mulch with them, it helps if you can spread them out somewhere and let them dry for a day or so, so they lose moisture and won’t mat together. (ETA: a commenter just reminded me to be careful if you are sourcing your grass clippings from outside your home. If the grass has been treated with pesticides or herbicides, you will bring those into your ecosystem.)

2) From your city. I can’t speak for all cities, but most have tree trimming crews, and they have to do something with all that stuff, so many cities have public piles of both compost and mulch for the taking. We often visit the free pile of mulch in Griffith Park, not far from the putting range. We only take their mulch, not their compost, which we’re a little suspicious of.

On that note, not all mulch is created equal. Check the pile before you start shoveling to make sure the wood is ground up enough–there shouldn’t be too many big chunks of wood. A few big chips are okay here and there, but it should be shredded, not just vaguely chopped up. There also shouldn’t be too much garbage mixed in–bits of plastic and the like.

3) From tree trimmers. Shredded tree trimmings are one of the best kinds of mulch we can use. When arborists or tree trimming crews are working in your area with a wood chipper in tow, go talk to them and ask if they have plans for all those trimmings. They may be willing to dump them in your driveway for free.

We recently posted about someone working on an app to unite tree trimmers with people who want mulch. This revealed that 1) sometimes getting those guys to deliver is easier said than done, and 2) that some areas already have networks which link up tree trimmers with mulch-needers.

As to point one, I’d say that you should just keep trying and be willing to pay a little if necessary. For our most recent mulch delivery, we actually paid our arborist’s crew $50 to bring us a mountain–a literal mountain–of mulch, enough to cover our front and back yards. It was worth the money.  As to point 2, check around and make sure that there isn’t a system already set up which you can take advantage of–talk to your neighbor with the richly mulched yard for a start. Where did they get theirs?

4) From the feed store. Straw (not hay!) can be used as mulch, and one bale will go a long way. Now, admittedly, it does make your yard look like the set of Hee Haw, but it works. We covered our entire back yard with straw one year, just for the hay of it. Generally speaking, I’d reserve straw for certain uses in the vegetable garden, which I’ll talk about in a bit.

5) From your recycling bin. It is possible to use shredded cardboard and paper as mulch. It can turn a little unsightly, but it is a nice way to return some paper to the soil. More often newspaper and cardboard are used in specialized gardening techniques like lasagne or sheet mulching, and in lawn killing.

sunflower seedling

This volunteer sunflower seedling is a little stressed, but I think it might do better now that it has a nice blanket of dead weeds.


Mulching perennials

It’s a fantastic idea to spread mulch under all your perennials–all your bushes and trees. In fact, I think this should be law. (If only I were Queen of the Universe!) About 3 inches (7-8 cm) is a good amount. (You use thicker mulch layers for killing lawn and repairing soil. In those cases you lay down something more like 8 inches (20 cm)).

You can also mulch fruit trees with compost instead of wood-based mulch, to give the soil life there a boost, or lay down an inch or so of compost, and then top with mulch.

When mulching your trees and bushes, be sure to leave a couple of inches between the mulch and their trunks. You don’t want the mulch creeping up the trunk–it’s not healthy for the wood.

Mulching your paths, seating and play areas

This is a great way to repress weeds, keeps down dust and mud and make your yard look tidy. It is also fundamentally pleasant to walk on a path of mulch.

Mulch used in open spaces like this can be applied fairly thickly, say 5″ (13 cm), so you have a solid layer which resists foot disruption and smothers the weeds. There’s no need to put anything under the mulch in these situations–not cardboard or newspaper or plastic.

A nice side benefit is that you are protecting and nourishing the soil in those areas, so that one day, if you decide to re-arrange your yard and plant in those spaces, the soil will be in much better shape than if it were paved over.

(ETA 5/15: A reader reminds me to mention that it is a good idea to leave some soil bare in a yard for native bees and other insects. Some native bees harvest dirt and mud for their nests, others nest in the ground and need access to the soil. I’m going to do a whole post on native bee habitat later in this series, so you’ll be hearing more about this. In the meantime, just keep in mind the idea of leaving the odd corner or bit of slope un-mulched.)

Mulching vegetables:

Mulch in the vegetable beds is potentially useful, but also has downsides. It’s very specific and local knowledge, so you have to see what works best for you.

I’ll say straight off that if slugs are a big pest in your vegetable beds, mulch will provide them with lots of nice habitat, so I’d not mulch anywhere near my vegetable beds in that case.

A mulch of clean, bouncy straw can be useful for keeping fruit off the soil. How did strawberries get their name, after all? They are traditionally grown on straw. Yes, indeed!

Erik and I mulch our tomato beds with straw. It insulates the soil and keeps low fruit off the soil. We wait to mulch the beds until after the seedlings are a few inches tall, out of bug noshing range, to be sure we don’t inadvertently host any chewing critters.

Same goes for squashes and pumpkins–sometimes it’s nice to put the ripening fruit on a straw cushion.

However, we don’t mulch our lettuces and leafy greens, though a straw mulch looks pretty among greens. Maybe if Garden Beautiful was visiting for a photo shoot, we’d do a temporary mulch for looks. But bugs that like to eat succulent greens seem to like to bed in mulch, so generally it’s a no-go for us.

All of what I said may not be true across the board. I hesitate to give generalized garden advice, because every situation is different.

Mulching California natives:

This is a charged topic. I can’t speak to native plants of any other region, but here in California we are often sternly advised not to mulch our native plants. I ignore this to a certain extent. In general, I understand the logic. Our chaparral plants are not denizens of Mirkwood Forest. They need sun and air and some dryness. In fact, some like to be dry all summer long. So while it might work for non-natives, it would be wrong to put them on a drip system that waters them weekly and then bury them under several inches of wood chips. They’d suffocate.

Nonetheless, as I said above, Mother Nature is not busy with her broom. All plants drop leaves, even natives, and I leave them in place. Sometimes leaves blow among them from other plants. I leave those, too. If I pull weeds around the natives, I leave those in place. As a result, my natives are lightly mulched, and seem happy enough about it.

Mulching your lawn:

Mulching is one of the best ways to kill your lawn. Instead of going through all the trouble of tilling or solarizing, just lay down a layer of cardboard and a super thick layer of mulch and wait. If you’re interested in doing this, check out this series from UC Davis “Stacey’s Lawn Removal” where a woman walks us through her lawn removal using this technique. As a bonus she has lots of planting suggestions, too.

Mulching your lead-contaminated yard:

Mulching is one way to minimize the impact of lead in your soil. If your soil tests positive for lead, all you can do, short of replacing all of it, is to cover it up. You could choose to pave your yard, or put down a lawn, but mulch is cheaper and easier, and more soil-life friendly than those options. It works by keeping the soil covered, so that lead-laden dust doesn’t swirl into the air, and it keeps little kids who are toddling around up and out of the dirt, so they don’t get it on their hands, and into their mouths.


Reapply your mulch as often as necessary. Sorry I can’t be more specific! Different mulches will break down at different rates in different climates. Just check your mulch levels and add a little more. This should be no more than an annual chore.


Some kinds of mulch kills plants:

Use some caution with leaves or wood from plants known to be allelopathic–that is, hostile to other plants, like eucalyptus and black walnut. It’s not as big of a problem as you might think. They haven’t been able to prove that cedar chips, for instance, actually inhibit plant growth, despite all their bad press. But it’s a nuanced situation, and this article by Linda Chalker-Scott is helpful in sorting out the details.

Mulch encourages termites:

Do termites feed on mulch? Yes, apparently so. But it’s complicated. The University of Florida IFAS Extension did a study on this, and decided, in their conclusion that we may as well keep using it:

Further research on mulches and termites is warranted to determine if we should be concerned about using mulch around houses. Also, research is needed on possible repellent mulches such as melaleuca which might serve as an additional barrier for household protection against termites. At this time the benefits of mulches such as water conservation, reduced used of herbicides, and reduced soil erosion are very apparent while the risks to termite infestations due to mulches are unknown. Homeowners will continue to use mulches in landscaping around their houses and buildings. Our current recommendation is to be vigilant and up-to-date with termite inspection and treatment.

Wood mulch robs nitrogen from the soil:

There is also a persistent rumor going around that wood chips or shredded wood mulch robs the soil, and thus your plants, of nitrogen, so you shouldn’t mulch with wood products. While it’s true that the carbon in the wood is looking for nitrogen in the soil as the wood breaks down, but the exchange is very slight, and will not inhibit your plants. Mulch encourages life in the soil, the vital, microscopic life which actually produces nitrogen to feed the plants. (Again, you’ve gotta read Teaming with Microbes!)  The good that mulch does for the soil vastly outweighs the small amount of nitrogen lost where the wood touches the soil.

Bad Mulch?

If any mulch could be considered “bad,” I’d have to point a finger at plastic sheeting and rubber mulches. The problem with these is that they don’t break down and feed the soil. They do some of what mulch is supposed to do, but ultimately, they are not friendly to the life of the soil. Worse, they linger eternally and I guarantee you that one day in the future you’ll be pulling up handfuls of the dratted stuff, cursing yourself for ever thinking it was a good idea to use it.

Gravel mulch and decomposed granite (D.G.)  is somewhere in between. It at least rock belongs in the soil, unlike plastic and rubber, but it doesn’t feed the soil, and almost always is installed with an ultimately problematic layer of plastic sheeting underneath. I could do a whole Tumblr of photos from our area of people who put down plastic sheeting and rock in hopes of having a trouble-free landscape, only to find themselves hosting a fine weed farm. It is far better to put organic mulch down on bare soil. I can’t say it enough–imitate nature and you’ll be fine. Try to be clever with man-made materials, and you’ll be looking at woe down the road.

I speak from experience. Long ago we put down a layer of plastic weed barrier beneath a decomposed granite surface in our yard. That idea didn’t work out and the granite is long gone, but the plastic, despite our efforts, still shows up when I’m digging around. More than a decade down the road, it is in tatters and shreds and is absolutely miserable to remove.

So, learn from our mistakes, and…

Love Your Mulch!