Ground conditions

September weather has been particularly wet across much of the east and south of the country.

Met Éireann’s September summary shows Casement, Dublin airport, Oak Park and the Phoenix Park to be around or over 200% of their 30-year averages for the month. Most other tillage regions are above 140% of average.

While most of these regions were dry, land does have a limit and rainfall amounts this week could be crucial for planting conditions.

Many growers have erred on the side of caution and not planted too early, but now it is important to get drilling done. Stubbles not cultivated must be drilled before the end of October.

Early sown crops are now fully emerged. These are mainly in areas with less risk from high virus infection. Planting is continuing but it is really only getting going in the south.

Herbicides

With weather now interrupting planting progress, there may be opportunities to get pre-emerge herbicides applied. Most of the effective grass and broadleaved weed herbicides need to be applied pre-emerge.

Products like Firebird and Flight will provide the main actives in most fields but some may need additional diflufenican or pendimethalin added.

These sprays are best applied before weed emergence, especially for grasses. Some fields will benefit from the addition of Acedex Factor.

Winter rape

Examine early sown crops for signs of downy mildew, light leafspot (LLS) or phoma infection. Overall foliar disease risk may be increased somewhat by the prevalence of brassica catch crops in your area.

Treatment of downy mildew may only be needed on later sown crops where phosphite might be applied to help plants fight the disease.

Treatment of phoma or LLS may be warranted if at least 25% of plants show 20% infection. This threshold should be higher when plants get bigger but lower on smaller later sown plants.

Infection is influenced by proximity to other crops or stubbles from last year, so do not take infection for granted.

Products like Fezan, Proline, or Prosaro might be used if disease levels warrant treatment. Some of these also act as growth regulators, which might be useful in advanced crops, but not on more backward ones.

The minimum rate for disease control will be half rate and higher rates give more growth regulation. Treatments may still be a few weeks away.

Planting

Increase seeding rates slightly now as seedbed conditions become more difficult. Soil temperatures remain 1-2°C above normal which helps autumn growth.

Get the most difficult fields sown first to give them the best chance. Easier ground can be planted later in the season.

Seed rate for wheat might be in the 250-280 seeds/m2 range or 125-140 kg/ha (8-10 st/ac) for 50g seed where conditions are good.

For winter barley, push towards 350-380 seeds/m2 with 175-190 kg/ha (11-12 st/ac) for 50g seed – hybrids at 200-225 seeds/m2. Oat planting will be getting underway at 350-380 seeds/m2, planting 140-155 kg/ha (9-10 st/ac) for 40g seed.