September is the month when we generally see a noticeable change in weather away from summer conditions into autumn. There is a clear difference in day length, with around 11hrs 45 minutes by the end of the month, compared to 16.5 hours in the height of summer. With this decrease in daylight also comes cooler conditions and, crucially, an increase in leaf wetness.
Looking at the weather across the UK from August shows we had an average of 91% growth potential (GP), which was actually slightly higher than last month and interesting looking back at last year's records the same as August 2022. Temperatures remained consistent with an average of 19.5°C highs, slightly lower than lasts year's 24°C AVG. Rainfall has eased through August for many, which has allowed for favourable conditions for renovation work. Base nitrogen requirements also remained consistent with and average of 5.4kg of Nitrogen per hectare each week.
An overview of the weather statistics for August can be found below. Click here if you want to review weather data in your region for August. To keep up to date with the weather throughout September, visit https://academy.agrovista.co.uk/category/weather
The beginning of September looks like the better conditions for the month, with temperatures remaining favourable and there being minimal days of rainfall. This will allow more windows of opportunities for those with maintenance to carry out. If overseeding work is being carried out, ensuring a good contact with the soil will allow the seed to utilise the moisture in the ground. Also, consider utilising plant growth regulators such as Prohexadione-calcium and trinexapac-ethyl to help in the development of new seed by holding back the competition from the existing mature plants in the sward, creating a more favourable environment for establishment. It is predicted that towards the end of the month the weather will break, with more frequent showers forecast.
Conditions will become more suitable for disease development in September, with an increase in moisture levels in both the soil and on the leaf surface. Therefore, it can be the start of following a site specific integrated pest management plan (IPM). Disease management will form part of this plan and preventative fungicide applications can be a useful tool for the turf manager. These applications will ideally be part of a sustainable approach, which includes carefully selected nutrition from an appropriate nitrogen source (one that isn't going to contribute to disease development), biostimulants, moisture management, including dew control as well as plant response elicitors. These can be utilised in a synergistic approach where each application complements the next in the effort to minimise disease outbreaks and maximise plant health.
Nutritional requirements will decrease as the month progresses, from around 5kg of Nitrogen per hectare each week at the start of the month to around just 2kg of nitrogen per hectare per week at then end of the month. Matching this, fertiliser inputs will help with disease management. Too much fertiliser applied will encourage disease in the soft new tissue growth. Too little inputs will also potentially encourage disease as the plant health is not at full strength to withstand disease pressure.
Adult crane fly activity has typically increased in September, and therefore being extra vigilant when on the turf for any increase in levels will help to accurately time Acelepryn applications. The adult flies commence egg laying almost immediately, with hatching and larvae emergence about two weeks later. You can check reported sightings of crane fly species on the Pest Tracker on the GreenCast website. To aid effective timing of treatment, ensure the product is in the soil around a month after recording them flying on the wing. Where chemical control is not authorised, entomopahogenic nematodes can be applied with warm soil temperatures and available moisture being ideal conditions to get the best out of an application. The entomopahogenic nematodes swim in the water film on soil particles in their bid to search out a larval host, useful information can be found here.
B.Sc (Hons) | BASIS | FACTS