A New Compost (Biochar / Grochar)

oops .... thought you are anti trying new stuff because I thought that you read her blogs and believe evertyhing she says

 

Nah, she's not a celeb (well, she may be a gardening celeb, but its no surprise to me you've not heard of her)

I've been reading her book (called "The Informed Gardener", or something like that). It sets out to debunk a number of practices that have been commonplace for-ever in gardeners folklore.

You should not put drainage in the bottom of containers - water flow is impeded when the substrate types change

You should remove all soil for plants (trees and shrubs, not annuals in modules!) before planting, and you should not "improve" the soil with compost / sand / etc

The Myth of Compost Tea (that's probably the one that send Dim off-on-one!)

Staking newly planted trees is a bad idea

and so on ...

She's a PhD from a respected .EDU and I dare say has some knowledge that would be valuable to us.

But whilst I have picked up some interesting insights from reading her book, and her writings on the Internet, they just raise more questions than they answer in my mind.

Most of her book is available (e.g. in "articles") on the web, I'll see if I can find a link

 

I don't see them as a competitor forum Dim, as you say very interesting stuff, but its not as though GC talks about growing weed in your loft! ... you'd get locked up for doing what they do, but not for posting a link to their site on this one

 

Have a look at this list of Myths, pick one/some have a read and let me know whether you think "raises more questions than it answers" or if it made you vow to never do it that way again

http://www.puyallup.wsu.edu/~linda chalker-scott/horticultural myths_files/index.html

 

I'm at [email protected]

 

She's a professor of horticulture from a pucker university. I wouldn't have described her as trying to be in the public eye, and I ain't asking you to follow her, but I'd appreciate your view on one of her myth busting articles (pick one that you have always done and see what you think of why she tells you its wrong)

Add a handful of bone meal to planting holes before installing shrubs and trees
http://www.puyallup.wsu.edu/~linda chalker-scott/horticultural myths_files/Myths/Bonemeal.pdf

Newly planted trees should be staked firmly and securely
http://www.puyallup.wsu.edu/~linda chalker-scott/horticultural myths_files/Myths/Staking.pdf

You shouldn’t disturb the rootball when transplanting trees and shrub
http://www.puyallup.wsu.edu/~linda chalker-scott/horticultural myths_files/Myths/Fragile roots.pdf

Watering plants on a hot sunny day will scorch their leaves
http://www.puyallup.wsu.edu/~linda chalker-scott/horticultural myths_files/Myths/Leaf scorch.pdf

 

Your Grandad's 'ash mountain' is mostly Potassium. Biochar is Carbon. Potash is a potassium fertiliser that makes hydrangeas a better blue colour and increases fruit levels on currants. Biochar changes the soil structure to make all its components work better for plant growth, carbon puts a framework in place for long term soil structure improvement. But you are right that 'horticultural charcoal' as it used to be called, was used in Britain long ago. Groundskeepers once used it to toughen up cricket pitches, tennis courts and football fields. The biochar increased the reach of the grass roots, helping grass stay strong in the face of repeatedly having its tips mowed off. Once chemical fertilisers came in, biochar fell by the wayside.

Potash/potassium is made by burning wood and giving off the carbon in it as carbon dioxide. Biochar is made by starting the wood on fire, then cutting off the air supply. The wood can't burn without oxygen but it's too hot to stop, so it goes into 'pyrolysis' mode and reduces to almost pure carbon.

I suppose the difference between 'horticultural charcoal' and 'biochar' is that we know a lot more about soil organisms like mycorrhizal fungi and understand how biochar increases their population. So we can add the mycorrhizae to the biochar to make sure it kicks off straight away

 

Mostly calcium, no?

although wood ash will raise the pH (having the opposite effect). I know you said "Potash" rather than "ash mountain", but as the two were mentioned close together I didn't want anyone to confuse the two. Wood ash contains Potash, but actually relatively little as the majority of ash is Calcium, so whilst it provides a useful source of Potash it also acts like Lime to make pH more Alkaline - don't use on Blueberries!

 

Its specifically the gardeners' folklore that Linda whatshername debunks. Gardeners' folklore existed long before science was the fine art that it has become. I'm slow to change, like you, but wide open to science demonstrating to me that something could be done better. I need quality science, including peer reviewed proof, rather than just a rant though! and as you know I don't read the tabloids, so the stuff they peddle won't even get onto my radar.

Well ... that fact has been known, and scientifically proven, for over a century. Few gardeners know about it though, so its not just Prof Linda W.H.N.'s rant.

(We may not be talking quite the same sort of thing, so possibly we are on different wavelengths. I'm talking about an inch of gravel in the bottom of a container, and my understanding is that it refers to crocks in a clay pot too, although I do have some serious questions that I have not seen answered - e.g. if you only have one hole in the pot does it need some help [crocks], i.e. does the "moisture transition to a different density substrate" issue have less significance than "there's only one hole for the moisture to exit through")

It would be for me, they only take a couple of weeks from sowing to planting out anyway - saving two weeks would be a miracle!

 

She advocated pruning the roots and removing ALL the soil/compost ... (with caveats).

This is a different one, that watering in sun will scortch the leaves. The Telegraph (I think) printed an article last year that questioned a number of things, like this one. I have plenty of personal evidence that water on leaves on plants in the greenhouse scorches them, dunno about outside ... but ... again ... I'd like to ask the question whether she is only referring to outside, or in the greenhouse too.