Grappling with Groundcover to Save My Soil

Groundcover.

It’s an attractive label on a plant pot. It promises low maintenance and laid back gardening.

When we moved, there was a lot of ‘groundcover’ plants in our beds. Euonymus fortunei ‘Emerald Gaiety,’ Cotoneaster, and Vinca minor – also known as Lesser periwinkle. After 5 years of tidying, lack of organic matter and absolutely NO mulching the Vinca minor (lesser periwinkle) and other groundcover plants had left behind a wasteland.

One particular patch in the front garden was dominated by Vinca.

After a day of pootling about with the kids, I thought I’d dig up a patch to see what was going on down there. It had grown so dense over the years, that I don’t remember ever having seen the earth.

What I found was that roots of the Vinca had exhausted all the soil completely. In fact, there were more roots than soil which hung in dried grey clumps in between the roots. And even more shocking – DEAD dried up worms!

Unbeknownst to me (that’s such a great word), the Vinca had been sending out an SOS to me every month, by drying out and trying to extend out of its border.

But it was to no avail.

I did not understand the plant language at this point or the message that it was sending me. It looked lush enough after a drenching of some chemical liquid feed – so what did I care?!

But, with no organic matter added to it over the years, there was nothing but dust beneath the Vinca’s roots.

By doing nothing, I had violated the law of return. That is, everything that is taken from the soil must be returned.

Sir Albert HowardWhatever is taken out of the soil must be returned in equal measure.

A plant that grows and uses nutrients and water must die and return those nutrients and organic matter to the soil.

Well, this evergreen, ground-covering plant had utterly sucked the life force out of this particular patch. There was no return and hadn’t been for many years.

As an evergreen, this Vinca had taken everything out in order to maintain itself and not given anything back. Plus I had tidied and trimmed and not put anything back either. I was only concerned with TIDINESS.

I confess I did at one point take a vacuum out to the front garden to suck up some leaves.

Although the patch of groundcovered madness that I’m talking about was only 1m by 1m square, I felt that I would probably find a similar story across the garden.

After some intensive lockdown reading about the wild, the soil and microbes, I did some real ‘soil’ searching.

I didn’t realize that just 1 teaspoon of soil contains “one billion bacteria, several yards of fungal filaments, several thousand protozoa, and scores of nematodes” (Source: The secret life of soil (Opens in a new window)).

It is quite literally a jungle down there – and I had come along and destroyed it with my mono-culture Vinca.

As the kids and I pulled up the Vinca, they commiserated with me at the lack of life in the soil. I’d been educating them about soil and compost as I had also been learning for the last month, so they also knew things looked bad.

It’s simple. Compost, mulch, and compost tea (and sometime mycorrhizal fungi) are the soil food web gardener’s tools, and it takes only three strategies to restore the soil food web using them: applying the proper kind of compost; mulching the right way, with the right kinds of organic matter; and applying actively aerated compost teas (AACTs)…Compost can inoculate an area with microbes to support a soil food web. Properly made compost contains the entire complement of soil food web microorganisms: fungi and bacteria, protozoa and nematodes.

“Teaming with Microbes (Opens in a new window),” p124

Well thank goodness for that. There was hope.

Diane Miessler’s book Grow Your Soil (Opens in a new window)also suggested thinking of your soil as a house and adding in the necessary elements to keep your household running smoothly – or soily?!

• Start with the roof (plants and cover crops to protect the soil)

• The walls (organic matter to keep the structure and foundations together)

• Ventilation and plumbing (provided by microbes and arthropods)

• A pantry (more organic matter and some biochar)

• A well stocked pantry (with some organic fertilizer)

• And a kitchen garden to provide more food in the future (e.g. compost and compost tea)

Grow your soil by adding organic matter

Since there was very little to work with I had to buy in some multipurpose compost and some topsoil just to add some organic mass. To this, I mixed in some of my own homemade compost.

Organic matter is the key to growing soil. This not only gives the soil structure, but also bring with it a host of beneficial microbes. They also help with the structure of the soil air pockets and crumb sticky structure.

Grow your soil by mulching with the right materials

Along with mulching with brown material (for perennials and shrubs) and green material if I had annuals and vegetables. Perennials and shrubs prefer fungally dominated soils, so prefer mulch that will attract fungi. Your annuals like bacterially dominated soils, so you want to give them green mulch that bacteria like.

Mulch provides the protection – either living or dead. I decided to add both. Since I was predominantly using perennials I mulched my compost and topsoil mix with some woodchip. I also planted in some mustard and Phacelia as a green cover which could be chopped down and mixed into the top level of the soil.

My mulch could also be enhanced by pouring over some protozoa soup. By adding grass cuttings (or you can use alfalfa or hay) and rainwater to a bucket and running a fish tank air stone through it for a few days, apparently, I could grow some wiggly protozoa. Then by adding this grassy soup on top of my mulch, the protozoa would gobble up the fungi and bacteria living on the organic matter and release some nutrients to the plants. (Find out more in Jeff Lowenfels & Wayne Lewis’s Book Teaming with Microbes (Opens in a new window))

This was all easy enough to do – so I added this all in too.

Grow your soil by using cover crops

Over the top of my mulch I scattered in some Mustard seed, Buckwheat and Phacelia. These would all provide a good cover for the bare patches that could be easily chopped and worked into the mulch to add more organic matter and food for the pantry.

Grow your soil by having a diverse range of plants

With my plants, I shuffled various things I had in the wrong places into this new patch. A few grasses, some sage that was not doing too well in pots, along with a bay tree. I also popped in a Monarda didyma ‘Pink lace,’ some lavender and a Salvia ‘Hot Lips,’ for the pollinators – et voila! All were plants with a sprinkle of some mycorrhizal fungi of course.

Grow your soil with organic nutrients

All my reading had recommended testing your soil to know what it needed, but as I had no soil left to test, I thought I’d give it a boost with some slow release fertilizer.

I’d also been researching how to make my own granular fertilizer with organic materials. So with the help of another helpful book Teaming with Nutrients (Opens in a new window)– I tried making “Grandpa Al’s Can’t Fail Recipe” made up of fish meal, kelp meal, dolomitic limestone and rock phosphate.

I sourced some sustainably farmed krill (Opens in a new window)which is full of calcium, phosphorus, ammonia, potassium and magnesium; also some kelp meal (Opens in a new window) as it contains lots of trace elements and promotes soil bacteria growths! YAY! I also added in some volcanic rock dust. I felt like a druid mixing up my concoction and adding it in.

I’d put in everything that I thought would help. Including time, effort, kiddy power – the lot.

I’m still working on the compost tea. That’s stage 2.

Now all I could do was wait.

If I wanted to have a happy garden, I must ally myself with my soil; study and help it to the utmost, untiringly. Always, the soil must come first.

–  Marion Cran, If I Where Beginning Again

After two months, I had a little dig around in the soil.

It had been raining heavily for several days, so the soil was wet, but not waterlogged. A good sign.

And there was a living, wriggling WORM! Hurrah.

Springtails or possibly symphylans were squiggling about in there too. They like to eat fungi, pollen, microbes and organic matter, again another good sign – I think.

The plants were flourishing – are flourishing. Even a tomato plant is doing well in there, despite no weekly potash feed.

There was life in the soil. I did a little dance of joy.

Enter my favourite garden dancer…Bob!