The Water Resources (Control of Agricultural Pollution) (Wales) Regulations 2021

Maximum nitrogen limits by crop

10.  The total amount of nitrogen permitted to be spread on any crop listed in the first column below is the figure given in the second column below, adjusted in accordance with the notes to the table and multiplied by the total area in hectares of that crop sown on the holding.

Maximum nitrogen

Crop	Permitted amount of nitrogen (kg)(a)	Standard yield (tonne/ha)
(a) An additional 80 kg per hectare is permitted to all crops grown in fields if the current or previous crop has had straw or paper sludge applied to it.
(b) An additional 20 kg per hectare is permitted on fields with shallow soil (other than shallow soils over sandstone).
(c) An additional 20 kg per hectare is permitted for every tonne that the expected yield exceeds the standard yield.
(d) An additional 40 kg per hectare is permitted to milling wheat varieties.
(e) This is inclusive of any nitrogen that is applied as an exemption to the closed period for manufactured nitrogen fertiliser. The permitted amount may be increased by up to 30 kg per hectare for every half tonne that expected yield exceeds the standard yield.
(f) An additional 40 kg per hectare is permitted to grass that is cut at least three times a year.
Asparagus	150	n/a
Autumn or early winter sown wheat	220(b) (c) (d)	8.0
Beetroot	350	n/a
Brussels sprouts	350	n/a
Cabbage	350	n/a
Calabrese	350	n/a
Cauliflower	350	n/a
Carrots	150	n/a
Celery	250	n/a
Courgettes	250	n/a
Dwarf bean	250	n/a
Field beans	0	n/a
Forage maize	150	n/a
Grass	300(f)	n/a
Leeks	350	n/a
Lettuce	250	n/a
Onions	250	n/a
Parsnips	250	n/a
Peas	0	n/a
Potatoes	270	n/a
Radish	150	n/a
Runner beans	250	n/a
Spring-sown wheat	180(c) (d)	7.0
Spring barley	150(c)	5.5
Sugar beet	150	n/a
Sugar beet	120	n/a
Swedes	150	n/a
Sweetcorn	250	n/a
Turnips	250	n/a
Winter barley	180(b) (c)	6.5
Winter oilseed rape	250(e)	3.5