Reducing input costs with nutrient management

In the example below we show how the use of manures could dramatically reduce input costs.

Example farm

In this case, the farm is a mixed dairy and arable farm with 150 cows and followers on 80 ha of grass, the farm has 110 ha of spring-sown crops.

The slurry and farmyard manure produced alongside the imported biosolids were used on the grass and spring sown crop. All of the manures were applied in the spring or on the grass mid-season.

• 50 ha of spring barley
• 35 ha of spring rape
• 25 ha of forage maize

The calculations below show the cost of bagged fertiliser for the whole farm, and the potential value of manures which could be applied. The cost of fertiliser for the crops has been valued as £36,403 and use of the manures (both produced on farm and imported) would reduce this by £8,236. This shows, by maximizing manures farmers are able to make significant savings.

Fertiliser

This section highlights the total cost if bagged fertilizer alone was used on the farm. Rate of application was based on AHDB’s RB209, and for the purpose of this exercise nutrient costs were assumed at £0.66/kg N, £0.55/kg P2O5 and £0.40 /kg K2O.

Rate of nutrient application (based on RB209) were:

	Nutrients recommended (kg/ha)
Crop	ha	N	P2O5	K2O
Dairy/heifer (150 cows)	80	240	75	70
Spring barley	50	140	105	95
Spring rape	35	120	60	50
Maize	25	100	55	175

The cost of these nutrients, if applied as manufactured fertiliser, would be:

	Nutrient cost (£)
	N	P2O5	K2O	Total
Dairy/heifer (150 cows)	12672	3300	2240	18212
Spring barley	4620	2888	1900	9408
Spring rape	2772	1155	700	4627
Maize	1650	756	1750	4156
Total	21714	8099	6590	36403

Manures produced and imported

Amounts of manures produced and imported were:

	t or m3
Slurry	1000
FYM	400
Biosolids	200

These manures were allocated to crops and provided nutrients as follows:

	Manure	rate t/ha	Manure nutrients kg/ha			Nutrient applied kg
Crop			N	P2O5	K2O	N	P2O5	K2O
Dairy/heifer (150 cows)	Slurry	10	10	12	25	800	960	2000
Spring barley	Biosolids	10	16	110	4	800	5500	200
Spring rape	FYM	11	7	35	103	245	1225	3605
Maize	Slurry	8	8	10	20	200	250	500

The values in the table above are crop available N (spring applied, incorporated in arable areas) and total P₂O₅ and K₂O.

The nutrient value of these manures (using fertiliser values above) was:

Nutrient value (£)
N	P2O5	K2O	Total
528	528	800	1856
528	3025	80	3633
162	674	1442	2277
132	138	200	470
1350	4364	2522	8236

Visit our Tools page for more information on nutrient and manure management.