Fungi, Compost Tea and Companion Planting with Comfrey

[Steve Sobeck]

It’s fortunate that we learn from our ‘failures’, as it’s given me an opportunity to grow, even when certain members of my garden community have not J  I’m sharing a few of my wins and losses in the hopes of sparking some ideas and maybe some constructive feedback.  First, some ‘good news’; there’s a fungus among us:                 

These are ‘wine cup’ mushrooms from a ‘forest floor’ mushroom kit growing in wood chips under our deck.  They have turned this heavily shaded damp area into a productive one.  We’re hoping the logs we’ve inoculated with spores in the same area will produce in the next year or two.

 

COMPOST TEA: I’ve been experimenting with brewing compost tea using the vermiculture compost from our basement worm-bin (fed with coffee grounds and kitchen scraps), mixed with a little molasses, fish ‘product’, dried kelp and some wood chips/soil from our mushroom patch and ‘brewed’ for ~18-24 hours in heavily aerated water.  It’s very interesting to observe all the life happening on those slides!   I’m working with Dane at Flowerfield Enterprises, and we’ve looked at a couple of different batches under the microscope.  We tweaked the recipe a little to get a better variety of microorganisms and more fungal strands.  Though this process feels a little bit like alchemy, I’ll attempt to design a few experiments next year that will help demonstrate at a macro level what we hope are the benefits of nurturing the micro level of our soil’s food web.  For now I’ve been using it as a foliar feed on our fruit and nut trees.   We’ve also done some soil testing and determined that our particular soil should benefit from a generous application of calcium (to make more of the existing nutrients more accessible to the plant life) and some natural phosphorous.

 

COMPANION PLANTING WITH COMFREY:  A couple of years ago I began planting comfrey, chickory, clovers and other ‘companion’ plants into mini guilds around our fruit and nut trees in order to establish mutually beneficial relationships among the plants.   I really love this concept and am hopeful that it will prove to be effective in the long run, however, I feel it’s worth reporting that after a couple of years, my results are at best ‘mixed’.  From the pictures below, you can see how similar trees are doing with and without their comfrey companions.  All trees were mulched with wood chips to increase fungal activity in the soil.  Half the trees have had comfrey planted as a companion plant for ‘chop and drop’ mulch and nutrient accumulation.  In most cases, after a couple of years, the trees with the comfrey seem to be growing less vigorously than those that have simply been mulched with wood chips.   I speculate that this is primarily due to the aggressive growth and competition of the comfrey plants and roots, which are in most cases doing much better than the trees they are supposed to be ‘helping’ J.  There may also be nitrogen depletion or other nutrient deficiencies as the comfrey leaves initially decompose.  I’m not giving up on this idea, but I think I need to make some adjustments – perhaps more frequent chopping, or more spacing between the comfrey plants and the tree.   I have noticed some beneficial effects of the comfrey in terms of attracting pollinators and serving as ‘sacrificial’ browse for some of the insect pests.  We’ll see what unfolds in the next couple of years.  Here are 3 sets of pictures from young pairs of hazelnut, cherry and almond trees for comparison so you can judge for yourself (sorry for the layout issues with these photos - I can't position them or line them up with text boxes in this posting tool)

 

 Above: Hazelnut without (left) and with (right) comfrey companion.  The shovel is my attempt to provide a measuring frame of reference.

 

Cherry tree with (left) and without (right) comfrey.  The leaves are starting to drop so it's hard to pickup the ouline of the trees, but you can see the much more vigorous branching and taller height of the tree on the right.

 

It’s harder to see in a small picture, but in general, the trees with the comfrey are smaller, less vigorous and have yellowed leaves that are dropping sooner. The 2 almond trees are similar in height, but the almond tree on the left without comfrey is actually 1 year younger and is broader and more vigorous.   I'll continue to experiment and keep you posted.  Many of my trees are in the 'creep' year of the 3-year 'sleep, creep and leap' cycle - so perhaps in the coming spring they will take off - a late-summer night's dream :).

That's enough rambling and incompetent picture layout posting for today.  I'd be interested in starting the group having a session/dialog about pest and disease control.  I've started experimenting with neam oil and water spray for control of some insects and disease.  We had a bad case of powdery mildew on our pumpkin and squash vines this year - I've also experimented with milk/water/baking soda and compost tea to partially control that - but I got a very late start on the spraying, hoping it wouldn't be needed.  Next year I'll try to be more vigilant early in the summer, before things get out of control.

Steve

[luckymortal]

Hi Steve, great "report." I'll be "stealing" that idea about mushrooms under the porch...

Interesting result on the comfrey. That's the result I expected when I planted these two nearly identical cherry bushes I got from PJ:

But for whatever reason, the plant with a bunch of chicory in its root zone is 10 inches taller and put on about twice as much mass as the one without competition!

This surprises me, because I have often observed fruit trees in the wild that appeared more productive and healthier than orchard trees, with thick, productive understories doubling the yield--but I have never seen a wild tree put on as much growth as mulched trees in orchard culture.

Personally, I consider the main benefits of underplanting as saving me time, work and money on mulching, while increasing biodiversity and providing additional yield. It might also help give necessary competition and create a better nutrient balance for plants like apricot and persimmon that suffer from TOO MUCH growth or fruit drop from too much relative nitrogen.

This is different than permaculture manuals from the tropics, where the combination of thin soils, plentiful rain and the solubility of nitrogen make competition for soil resources less important, and most nutrients are bound up in plants anyway.... Geoff Lawton certainly gets better results with mass underplantings than he would with conventional (temperate) orchard culture inappropriately imported by farmers from northern climes.

I assume this is why many temperate gardeners like Toby Hemmenway advocate for plantings that space out "mulch makers" such that they actually free up space in the tree's root zone, rather than competing with it.

This apricot guild looks pretty dense.

But "chop and drop" and the sprawling form of these companions actually creates quite a lot of "open space" for new tree roots to spread out and explore. My guilds typically have <1 plant/SF inside drip zones. And every time you "chop," a corresponding mass of plant roots die back, providing a fertilized, tilled soil for your tree roots to spread through.

Anyway, "guilding" is pretty new technique, so there's a lot to play around with. Do you think you'll try to change things around a bit?

[luckymortal]

One last thought... a quick search revealed quite a few annecdotes (from temperate gardeners) of comfrey stealing nitrogen from trees and halting the growth. These appear be in cases where C. was planted in close proximity to the trees. In one such case on the Permies forum, folks recommended planting more N fixers to balance out the equation. Others suggested more frequent chopping to "free up" the N.

A nitrogen comparison between those soils would be interesting.

Of course, the conventional university extension wisdom says BURIED wood chips will rob soil of nitrogen by binding it up with the decomposing wood. It would make sense that "buying" the wood chips with your chopped comfrey could do the same.

So perhaps you could consider pulling back the wood chip mulch in a few places and mulching with comfrey directly on the soil? Otherwise, for a few years the nitrogen gulping comfrey might be essentially draining n from the root zone UNDER the wood chips, then essentially feeding it to decomposing wood where the tree can't get to it. OF course, then you loose the fugal power...

[pjch...@gmail.com]

Sorry to resurrect an old topic, but I saw this article today on the PRI site and it reminded me of Steve's findings here. So in this page I'm linking to, comfrey (coupled with sheet mulching) is said to have improved soil organic matter and mineral content, as shown with soil tests before/after...however I don't think a "competition-with-trees" factor is mentioned or accounted for, and the testing wasn't very scientific with regard to control plots.

In my own experience, on my dry, sandy soils (SW Michigan, zone 5b, ~34″ rainfall/yr., flat terrain), I have a hard time just keeping comfrey alive. Even in areas where it’s planted into a sheet mulch near a young tree, it is hardly thriving after 3 years in the ground (nor are most of the trees putting on a lot of growth; not sure if that’s causation or just correlation—in most cases there are 2 comfrey plants per tree, each planted maybe 2′ from the trunk on opposite sides in a 4-5′ ring of sheet mulch). However, where I’ve planted comfrey into hugelkultur beds, richer soils, or spots that get watered more, it has done better and I’m able to chop a decent amount of it for biomass and mulch a few times per year.

I mentioned Steve's findings in a comment on this page; so far nobody has responded to it specifically.
http://permaculturenews.org/2014/03/18/comfrey-really-improve-soil/

PJ