The weather has been broken and has made it difficult to get out with the sprayer, so timings on some things are a little bit off, but drier weather is in the forecast.


If you have not yet sprayed for BYDV you can still do so up until GS30, but the application has less effect on yield and may result in harm to natural predators. Teagasc research shows that applying an aphicide at first node produced a yield of 5.1t/ha, compared to 5.6t/ha when applied at the four-leaf stage. There is no advantage to applying more than one aphicide to a crop. It will contribute to the build-up of resistance to pyrethroid sprays and then those sprays will become ineffective.


Crops being sprayed for weeds now are getting big, so they should be sprayed as soon as possible to ensure you hit the weeds. You’ll need a sulphonyl urea product, which will change with the weed spectrum, and a tank partner like fluroxypyr or Arlyex, Binder or Pixxaro. In many cases, or on late April and May sown crops, it is still time enough to apply a plant growth regulator to help with tillers.


Ensuring crops have the nutrition they need early in the season is essential. If a crop is deficient in a nutrient like manganese or magnesium for example, and the leaves turn yellow or have brown spots, then this shows that the plant is stressed and is being affected by the deficiency. If a plant is stressed then this creates an ideal environment for disease to attack. Some diseases like ramularia are particularly affected by stress. So early treatment of nutrient deficiencies can help to prevent bad disease later on.

Disease control

Spring crops are growing fast and current weather is ideal for many diseases, so it is good to keep those at bay. Adding some fungicide to the herbicide application can help to keep away disease like net blotch. Many crops are now at mid to late-tillering, so it’s an ideal time for a fungicide application. Early-sown crops are well on and should have received a T1 fungicide by now in most cases. Spring oats are at similar stages – add a mildewcide to spring oat crops where needed. Many winter oat crops are due their final fungicide when the head is out.

Grass weed control in beans: Early-sown bean crops are powering on and getting tall. Remember, you should ideally spray for grass weeds before crops start to flower. Falcon is a product for this timing, if you miss this timing then Stratos Ultra can be used. The first fungicide should be applied at the start of flowering.


It is important to get the right advice on your crops, so make sure you are dealing with a trained pesticide adviser. You can look up the list of registered pesticide advisers on the Department of Agriculture’s Pesticide Registration and Control Division’s website.