Soil analysis advice

[HHouse]

Can anybody tell me what to do about a soil analysis that shows a normal pH, v high phosphorous, normal potassium and v high magnesium?
That's all the info it gave me. The pH is actually quite variable across the field (5 acres), but averages 6. There are lots of buttercups in patches.
I use it to take hay from (it's basic native grasses - lots of Yorkshire Fog). Wet land, there's a spring in it.
Very poor crop last year - v low protein and nutrients, v low mineral analysis. But had been sheep grazed quite hard over the winter before, and then the drought. Haven't touched it after hay cut in July.
Limed end of 2021.
Hope somebody in the know can suggest a good plan

 

[Jonny_2]

If ph is 6 then some more lime would help. High phos is a good thing, expensive and hard to put right. If your just going to graze it then straight nitrogen will be fine, or if cutting the a nitrogen/potassium product so you replace your off take

 

[HHouse]

Thanks Jonny_2 - so would you lime asap and then nitrogen/potassium bit further towards spring? Will be wanting to cut hay this year

 

[Sir loin]

I am in exactly the same position and I think your high mag locks up the potash (may need to be corrected on that). so I am applying MOP to my cutting ground plus urea for nitrogen (not bought yet)but urea will be little as high clover content in ley.
Could do with knowing how much MOP to apply for maintenance soil tests show average index 2.5 for potash.

 

[HHouse]

I am in exactly the same position and I think your high mag locks up the potash (may need to be corrected on that). so I am applying MOP to my cutting ground plus urea for nitrogen (not bought yet)but urea will be little as high clover content in ley.
Could do with knowing how much MOP to apply for maintenance soil tests show average index 2.5 for potash.

Not sure if this is of relevance but hay actually had levels of potassium at 1.6%, classed as low, but fine for what I need it for. all else was low and v low

 

[ollie989898]

If you have normal or high phosphate/potash and very high magnesium there is little you will do to alter that.

A bit of lime wouldn't go amiss but your main problem last year I'd say was drought.

 

[Sir loin]

My FIL very clever man told me that you will only deplete you P & K if you take lots of little cuts of grass . When grass is mature the P & K are returned to the roots thus not depleting your indexes when you harvest the crop.

 

[ollie989898]

My FIL very clever man told me that you will only deplete you P & K if you take lots of little cuts of grass . When grass is mature the P & K are returned to the roots thus not depleting your indexes.

You would have to go some to seriously deplete a soil of P and K- I reckon you would probably make a dent in the potash in an average season if you applied a lot of fertiliser and cut it 4 times for silage. The rest, no chance.

 

[HHouse]

My FIL very clever man told me that you will only deplete you P & K if you take lots of little cuts of grass . When grass is mature the P & K are returned to the roots thus not depleting your indexes when you harvest the crop.

Makes sense. One cut a year for past three years, no fert.

 

[ollie989898]

If you want a better quality end product you will need to cut earlier though I accept you are at the mercy of the weather and the grass species you have. If you want some serious production out of it a reseed may be in order.

 

[Derrick Hughes]

No point liming if its 6
Fact is field is in its natural state,nitrogen will help a little , but if you want a vast improvement then reseeding is the only thing that will help , but then if its a traditional meadow you may not be allowed to

 

[M-J-G]

No point liming if its 6
Fact is field is in its natural state,nitrogen will help a little , but if you want a vast improvement then reseeding is the only thing that will help , but then if its a traditional meadow you may not be allowed to

This could be totally incorrect.

It is very often the case that in areas where Mg is high that you have to apply Ca Lime even if the ph is ideal, Ca/Mg balance is critical for soil function

 

[haybob]

Old boy near me says sulphur has made a big difference to his permanent pastures.

 

[Derrick Hughes]

This could be totally incorrect.

It is very often the case that in areas where Mg is high that you have to apply Ca Lime even if the ph is ideal, Ca/Mg balance is critical for soil function

You learn something everyday
I was told to use Gypsum if ph is over 6 to correct high mag , but without seeing the analysis we don't know if its critically high

 

[alomy75]

pH 6 depending on grass species is on the low side. 6.5 would be my target

 

[Kiwi Pete]

This could be totally incorrect.

It is very often the case that in areas where Mg is high that you have to apply Ca Lime even if the ph is ideal, Ca/Mg balance is critical for soil function

100% this

 

[M-J-G]

You learn something everyday
I was told to use Gypsum if ph is over 6 to correct high mag , but without seeing the analysis we don't know if its critically high

Gypsum or Ca Lime, mg doesn't need to be critically high, if it's high at all and Ca is low the balance is well out and soil structure along with the ability to handle water are compromised.

In war times the army used to spread mg lime on strips of land because it made the land so hard and dense that they could land planes on it.

 

[workin f nowt]

Can anybody tell me what to do about a soil analysis that shows a normal pH, v high phosphorous, normal potassium and v high magnesium?

That's all the info it gave me. The pH is actually quite variable across the field (5 acres), but averages 6. There are lots of buttercups in patches.

I use it to take hay from (it's basic native grasses - lots of Yorkshire Fog). Wet land, there's a spring in it.

Very poor crop last year - v low protein and nutrients, v low mineral analysis. But had been sheep grazed quite hard over the winter before, and then the drought. Haven't touched it after hay cut in July.

Limed end of 2021.

Hope somebody in the know can suggest a good plan


Cal lime

 

[SilliamWhale]

My FIL very clever man told me that you will only deplete you P & K if you take lots of little cuts of grass . When grass is mature the P & K are returned to the roots thus not depleting your indexes when you harvest the crop.

That's true of cereals at maturity I think

 

[DrDunc]

pH 6 depending on grass species is on the low side. 6.5 would be my target

Also depends upon the type of soil

Up here in the hills where peat prevails, you want a pH between 5.8 and 6.2

High magnesium level will be locking up nutrient availability, so calcium lime or better yet gypsum will make a big difference

Lots of Yorkshire Fog suggests a reseed will herald the greatest improvement in feed protein and energy quality

As the field hasn't been grazed since it was cut last July, it's already full of dead thatch that will lower forage quality. A rake with an einbock type harrows will give more growth, but only worth doing if there is some ryegrass left among the weeds