Clay!

[crucy86]

Hi All,

I posted a while back as I had received my first ever plot at the end of the last year. I covered the plot over winter until a week or so ago.

In my eagerness I hired a rotavator and went over the plot several times (it was full of weeds etc however I did confirm there was nothing there like couch grass etc).

I knew that if the soil was too wet it may cause issues, however when I read up online it said that as long as you can break apart a clump with your thumb, after squeezing a ball in your hand then it should be OK. So I dug down about a foot, tested and it seemed quite crumbly so I wen on ahead.

I now however have a nice neat plot but with rock hard lumps on top golf ball size, I always kind of knew this may happen so cant really complain too much! the soil underneath though seems better, although its obvious my plot has quite a bit of clay and its never had anything mixed into it (the allotments are new, about 2 years old and the previous tenant didn't do much)

so the question is, how do I improve it? I know i need to add organic matter, compost, manure etc - but can anyone give any specific advice, I have access to unlimited horse manure however cant confirm its not been contaminated with that horrible weed killer so reluctant to use it. Its going to take a while to build up my own compost supplies but I did consider splashing out and buying in a large amount to mix in? I've also heard sawdust is good but will rob the soil of nitrogen whilst it breaks down before giving it back?

can anyone offer any advice ?

[alldigging]

If it's free pile it on>
If you have different lots of stuff that are free then make a lasagne bed and grow in that.

You can test the muck by planting a bean in it - if it grows it's fine.

[crucy86]

Thanks for your reply,

a family member owns a stable so I really do have quite a big supply I can use, she unfortunately cant verify if any chemicals were used, its also a possible that she has purchased different batches from different people so the muck heap will have lots of different types mixed in!

I can prob tell from how rotted it is as to what time it was - so is the bean test perfectly fine to try? I didnt know if it was that conclusive? so I grow 2 beans, then transfer them into 2 different pots, one with manure added and one without and then check the growth?

I have some french beans just sprouting so could use a couple?

with the manure, can it mix in as it is and then be grown in this year (with the exception of root crops)

Thanks,

Craig

[alldigging]

Weedkiller in manure / Royal Horticultural Society

Tbh if you've got really clay soil then I'd just get as much well rotted stuff as possible and put it on.

[Mr Bones]

You could try sowing batches of clover (sold as green manure) in samples taken from the stable muck heap.

[Kristen]

I would be more cautious. Difficult to tell if parts of the manure heap have Aminopyralid contamination as the main problem, as I see it, is that if you put the manure on the land and subsequently find that parts of it were contaminated there is no easy way to get rid of it - it can require cultivation of the land for several years before it breaks down and becomes harmless.

Newer manure might be a better bet. The requirements for notification, when Aminopyralid is used, have become more stringent, so it is much more likely that the owner would know if they had been used since (including on bought-in hay as well as any paddocks which were treated with herbicides by, say, contractors)

[MartinRSharpe]

I have to agree with Kristen.

Most of the sprays used on horse pasture specifically kill broad leaf plants but some of them also effect legumes.

Aminopyralid in theory has a half life (i.e. half of what is there breaks down) less than a day in water and around 2 months in soil when exposed to sunlight. Not exposed to sunlight the half life is closer to 2 years.

In theory anyone using Aminopyralid should have it documented and have been "trained" in using it. In practice however......

[Two_Sheds]

how do I improve it? I know i need to add organic matter, compost, manure etc - but can anyone give any specific advice

well I'm going to tell you what you already worked out for yourself: add homemade compost. Of course it's going to take a while to make, but what's the rush? Plants will grow in your soil anyway. If weeds grow, veg will grow: they're all plants.

Shop bought (mpc) isn't the same thing, and it's too light & fluffy, not to mention expensive, to add to your plot.
Make do with starting your seedlings in MPC, and plant them out when big enough to survive. That way you're adding a little bit of MPC at a time.

[Kristen]

As a one-time-get-your-started organic matter it would be worth considering mushroom compost (tends to be alkaline, but I don't think it will matter just-the-once) or spent hops if you are somewhere near a brewery.

[Kristen]

Aminopyralid in theory has a half life (i.e. half of what is there breaks down) less than a day in water and around 2 months in soil when exposed to sunlight. Not exposed to sunlight the half life is closer to 2 years.

My understanding (could well me wrong!) is that it persists in other plant material - so if in the soil (for 2 years) and absorbed by other plant material, then that decaying plant material can pass it to other plants, and the cycle continues. No doubt weakening each time, but its going to be a royal PITA to get rid of, once acquired.

[MartinRSharpe]

My understanding (could well me wrong!) is that it persists in other plant material - so if in the soil (for 2 years) and absorbed by other plant material, then that decaying plant material can pass it to other plants, and the cycle continues. No doubt weakening each time, but its going to be a royal PITA to get rid of, once acquired.

Essentially yes, it binds to the lignin of the grass. When the lignin in the grass is broken down (rotting or digested) it is then released.

Once released into the soil it actually breaks down.

[crucy86]

Thanks to everyone who has replied

I now have a plan of action! I will attempt to grow a crop in some test manure (from various places) but I think ill still leave that as a last resort. I know I definitly cant change the soil structure instantly (as much as I would love to be able to!) and its a slow process over years.

I have contacted some local brewerys to see if I can get access to spent hops too! Im also looking around for mushroom compost

I think a case of slow and steady will win the race!

can anyone recomend good crops for clay soil? will it just be things like carrots, parsnips etc I will struggle with?

[rustylady]

You shouldn't really struggle with any crops. Carrots and parsnips may not turn out long and straight like supermarket ones, but they will be perfectly edible.

[Madasafish]

We have clay.

Pile compost on top : don't dig it in except maybe the top 4-5cms of soil - otherwise it vanishes..

Raised beds for salads, radishes, strawberries as clay is cold and delays germination.

Potatoes etc are OK - I use cloches to speed up germination...

[crucy86]

Thanks

Ive been emailing around and found somewhere that will give me unlimited spent hops - If I dig them into the soil, are they likely to rob nitrogen like sawdust would as they start to break down? can I combat that by adding a fert?

Thanks,

Craig