Sports Turf Agronomy Advice - May 2024
When doing the monthly agronomy diary, you build up a picture of what the conditions have been like over a period of time.
As we now head into May, it is interesting to see that conditions over the last month have felt very different in comparison to the last couple of years; however, in terms of GDD, this April was very similar to last year. GP has been higher which is why it feels that there has been more growth this year compared to previous years, when it has been slow. Unfortunately, coinciding with this, there has been the significant volume of rainfall which has meant that keeping on top of the growth with regular mowing has been a big challenge for turf managers.
Before we look ahead to the forecasted weather for May, let’s look back at April’s average figures. The rainfall figures highlight just how much the rain has continued to fall; on top of last month’s average of 100mm, there has been a further 94.5mm this month. Fortunately, there have been some breaks in the weather which has allowed time for mowing to take place to start to refine areas. Any subsequent rain is interrupting this process, as the ground is so saturated it just tops everything back up and sets most sites back. It is amazing how quickly areas do dry though, once they have a period without rain.
Click here if you want to review weather data in your region for April. To keep up to date with the weather throughout May visit https://academy.agrovista.co.uk/category/weather
Looking ahead to the forecast for May, fortunately conditions look more favourable and rainfall is predicted to be much lower. There are 17 days of the month showing as 16°C or above, which will be beneficial for continued spring growth and recovery and, importantly, the night-time temperatures are consistently up above 8°. In recent years, May has been a month where the weather has turned poor and provided challenges for spring growth, so it is encouraging to see that after the incredibly wet start to the year, conditions are starting to be conducive for effective turf management.
Ensuring nutritional inputs are managed carefully, this month will be a key factor in how quickly surface quality can be achieved. The plant has been under significant stress, given the high moisture levels, and although previous applications may have been made, nutrition may have been lost via leaching and, therefore, following a ‘calendar’ application approach may lead to a shortfall in available nutrition, which may be at the detriment to surface performance. Many will switch from granular applications to liquid products, which have the flexibility to be applied little and often to give regular, balanced amounts of nutrient inputs. This can help to mitigate stress and provide consistent even growth.
Surfactants, as unlikely as that may seem, given the amount of rainfall we have had, will become an important tool in the toolbox this month. Conditions over winter will have led to a decrease in the rate of decomposition of dead and decaying organic matter. This will have increased thatch levels in the upper surface and, accompanied with shallow rooting, again a symptom of the wet conditions, will mean that once drying commences, the flip from wet to dry can be surprisingly rapid. To this end, it is prudent to use an application of surfactant to the soil to ensure even moisture distribution throughout the profile and reduce any cases of localised dry patch. Added into this can be the use of biostimulants, such as seaweed and amino acids, which again will mitigate stress but also promote new spring rooting.
Possibly another symptom of the wet weather is the recent increase in reports of leatherjacket activity. Chemical control for this pest will be largely ineffective at this time due to the size of the larvae; if damage is significant, there is the option to consider of a spring application of nematodes to try to combat the problem. Steinernema feltiae can be used at soil temperatures above 8°C and Steinernema carpocapsae above 13°C; therefore, it’s important to choose the right treatment for your site at this time of year. Towards the end of May, you may start to notice chafer beetle activity and, if so, then recording sightings and monitoring activity to plan an effective management tragedy over the coming weeks is highly recommended.
The forecast looks good for May, so let’s hope that comes to fruition and it continues well into the summer months - we need it.
Tom Wood
B.Sc (Hons) | BASIS | FACTs