Land is wet: Rainfall levels over the past week have left land wet all around the country.

While eastern tillage regions remain among the areas that have received the least rainfall so far in February, most areas are now over 70mm, with double that in parts of the west.

Interestingly, areas around mid and east Leinster are now almost up to their combined January plus February long-term average rainfall amounts, while south Leinster and down into Cork still have to get a lot of rain if they are to come close to their long-term averages for these two months.

Soil and air temperatures have dropped again and that is good to slow forward crops.

A spell of slow or no growth will still happen, so you would not want to be caught with a lot of nitrogen out in a wet spell.

Fertiliser: Stay out of fields with fertiliser for as long as ground is wet.

While temperatures remain on the low side, there is no pressure either way. This time last year, things were beginning to look up and yet it was well into May before growth really got going.

We could see plant development alright, but growth rates did not match up with the amount of nitrogen (N) available.

N cannot drive growth unless weather conditions allow. Photosynthesis is temperature driven.

It is now important to have your immediate fertiliser requirement on hand for when an application opportunity occurs.

It is also important to know what you plan to do in each field – if crop prices increase significantly in May, you can always apply more then. But should prices drop, you cannot take back the fertiliser.

Remember, there may still be more nutrient than normal available to crops this year.

This is because big canopies are already produced and roots are probably deeper. You need to make the best possible use of this.

Sulphur: One of the additional challenges around nitrogen application is to get sulphur applied.

This is important on all worn land that does not get regular organic fertilisers. Sulphur is important for the efficient use of N (as is potash) and a deficiency looks like a shortage of nitrogen.

Cereal crops require about 15kg S/ha for high yields and no more than that will be needed.

Sulphur can be applied in a single early or in multiple splits. It needs to be in the ground to help with peak N uptake and assimilation. Rape will need 30kg S/ha for good yield potential.

Applying 15kg of S on cereal crops will require 250kg/ha of a 6% S product (2 x 50kg bags/ac) which is easily achieved across one or more applications.

Getting 30kg S/ha applied to winter rape is more of a challenge. It would take 500kg/ha of a 6% S product, which would supply too much nitrogen.

So, high sulphur nitrogen products like ASN or sulphate of ammonia should be used.

With ASN, 220kg/ha (1.8 x 50kg bags/ac) would apply 57kg N/ha plus 30.8kg S/ha. Alternatively, 125kg/ha (1 x 50kg bag/ac) of sulphate of ammonia would apply 25kg N/ha plus 30kg S/ha.