Coal dust in soil

[rinabean]

How do you make use of soil that's full of coal dust? They used to sell coal out of this house until the early eighties when my in-laws bought it. It was stacked around the back where the patio now is. MIL says she's tried digging a flower bed before and they all gave up quite quickly. But, the cracks in the paving are full of healthy weeds and grass, so it can't be that unsuitable for plant life. I don't want to dig it all out and replace it, I want to work with what's there. If the weeds are thriving, and this is about five years after MIL's failed attempt, should I risk planting something into it? I don't mind adding a little compost for them, I'm not cruel, haha! Or any ideas on how to purify the soil with plants (probably weeds)? There's got to be some way to make use of it as I know people used to add coal (ashes?) to their gardens on purpose. I don't even know what properties coal has as a soil conditioner/contaminant, just that it's "good" or "bad"

I'd appreciate any ideas, especially any experience

[alldigging]

Wood ash yes, coal ash no. It's supposed to have nasty stuff in it.

What about raised beds with new top soil? Or just flowers?

[taff]

my fathers garden is a whole lot of coal ash, coal was stored on top of it, and added to it as ash for years and years. I've only just converted him to composting, but he's managed to grow beans/courgettes/herbs/roses/fuschias/daisies/rhubarb/primroses etc etc successfully since i was a kid, so it's not that bad
The soil actually looks like ground up coal, and it's fine, dry and loose. He's not added anything to it that I know of except spent compost from the hanging baskets.
I'd add compost if you can, if it's like his, it doesn't hold onto moisture very well.

[Feral007]

We are getting our farm soil tested to add minerals to it that it needs. It's quite expensive but it's 30 samples mixed. Surely there is some gardening place that could do a cheaper but similar test.

That way you are working with what you have, but also adding what you need. If it was cheap enough that is the way I'd go. And if not then I'd do what we are doing and make a no dig garden over the top of the coal dust and let the good stuff from the no dig garden filter down to improve the soil as you're growing above it. It's a good way to improve the soil while still growing.

[Feral007]

And if you want to do things by observation, just take note each time you plant out, which plants do well, and which ones don't. Then have a look at the plants that didn't do well - what do those plants need in minerals? And then add some of that! The plants can tell you for free but it takes longer.

[Two_Sheds]

MIL says she's tried digging a flower bed before and they all gave up quite quickly

That could be down to the poor soil, or the wrong conditions, or your MiL's gardening skills

the cracks in the paving are full of healthy weeds and grass, so it can't be that unsuitable for plant life.

What weeds are they, out of interest?

The soil is contaminated (with coal). Have a read of this article if you want to frighten yourself about contaminants in our gardens and allotments.

Its advice boils down to this:

Where garden soils are found to be contaminated, dietary exposure can be prevented by not growing food crops in the soil, possibly using grow-bags or tubs of clean soil instead.

Where the contamination is not severe, it would be possible to grow crops which accumulated elatively low concentrations of potentially toxic elements and avoid the high accumulating crops such as spinach and lettuce*

Soil ingestion and inhalation can be prevented by covering the contaminated soil with either a cover of clean soil** ... or paving with an impermeable surface.

In extreme cases, the soil may need to be removed


* I guess it would be possible to grow a sacrificial crop of something that would soak up the contaminants. I wouldn't be able to guess what to use though, or how many years that would take

** I infer that this means raised beds: you can fill them with either screened topsoil, or do a lasagne bed if you want cheap

[Two_Sheds]

* I guess it would be possible to grow a sacrificial crop of something that would soak up the contaminants.

... but it does take years & years

Phytoremediation uses plants to clean up contaminated soil...hyperaccumulators

MINERS NEWS - National & International news from the hard rock, coal, heavy equipment, aggregates & mining industries - for over 20 years

Phytoremediation and Medicinal Plants Research Laboratory

[dominic10]

Half of our allotment has been used for bonfires and the burial of plastic bags. We have removed 67 of them largely intact but some have disintegrated over time. We have decided to build raised beds and will purchase top soil in 1000 litre bags for £36 - this is about the size of a builders bag. We feel this is worth paying for peace of mind. I grew up in a mining area and there was a wharf close to our house where coal was stored in the open air in huge piles. Weeds grew in abundance when the coal was sold. Now the area is public land with trees and shrubs. Coal cinders are toxic, wood ash is fine. I am very interested in the info provided by 2S.

[donnakebab]

Why would somebody bury plastic bags? People used to make cinder paths on our allotment site years ago. Haven't found any on mine thank goodness.

[Thelma Sanders]

If it's coal dust rather than coal ashes(ie not burnt) I don't think it's as much of a problem. Try a simple soil test kit and see what the soil nutrients are like - to see if conditions can be easily rectified.

Especially as you're growing flowers? (veg growing wasn't mentioned in first post) I'd try growing some of the more basic plants - grasses and daisies first to see what happens.

[taff]

mushrooms are apparently good at removing heavy metals..

[bearded bloke]

Do you have nieghbours nearby ?
What if anything are they growing ?
What if anything did they do to the soil to achieve said growth ?

[rinabean]

That could be down to the poor soil, or the wrong conditions, or your MiL's gardening skills

You might be on to something, actually! She's not really a gardener. If it has problems with holding onto moisture, then that makes it the opposite of the rest of the garden, and most things she's killed has been by not watering them. (She doesn't have potted plants for this reason.) I hope it's a problem as easily rectified as this.

What weeds are they, out of interest?

Apart from the grasses, which are the majority, there's dandelions (loads), two foxgloves, ordinary violets (in the shade), a red leaved weed with pink flowers (herb robert? quite a bit of it anyway), and a low-growing one with little yellow flowers (looks like a sort of thyme but the leaves don't seem to have a scent).

Especially as you're growing flowers? (veg growing wasn't mentioned in first post) I'd try growing some of the more basic plants - grasses and daisies first to see what happens.

I'd like to take up some slabs for my grapevines. They are in flower buckets and they're okay but I know they'd be happier with some room under them. I can grow them over a building and they'll be fairly sheltered. If I plant them out in the garden proper, I don't think they could handle the wind. I've already been cruel and moved them permanently outside last summer when they'd been in a greenhouse for 20 years! Veg growing is my ultimate aim but my MIL might take some convincing, haha! I really don't want to kill the grapes because I inherited them, and I don't want to kill me with poisonous grapes either...


I'll see about getting a soil test kit. It might have to be raised beds, but I'm hoping to avoid that as I'm nearly out of compost. I might try lasagne beds. Thanks everyone for your help

[Two_Sheds]

Why would somebody bury plastic bags?

- to see if they biodegrade (they don't)
- because they're too thick/lazy to put them in the bin, so they drop them in the composter instead

a red leaved weed with pink flowers (herb robert? quite a bit of it anyway), and a low-growing one with little yellow flowers

Yep, herb robert, and the yellow one might be bird's foot trefoil
We have lots of BFT on the tarmac paths at the lotty ~ it tolerates poor drainage and only an inch of soil