Expected weather for this month:

On the cool side throughout April, with most of the light rain isolated to the South.

Key Tasks for April

The emphasis at this time of the year will be on mowing frequency, as long as there is sufficient moisture within the soil:

  • Apply 'little and often' foliar feed, consisting of mainly Nitrogen, with other nutrients and ingredients, such as Potassium.
  • Continue to seed sparse or bare areas.

Mowing. Greens should be mown at least three times a week, with some grooming, verti-cutting or brushing being undertaken on a weekly or twice weekly cycle to improve air movement and reduce thatch levels building up in the sward profile.

The sward will be actively growing due to the increased soil temperatures, coupled with the stimulation of fertiliser applications. Regular mowing will be required to maintain sward height at around 4-5mm. Verti-cutting/grooming fortnightly can be carried out to help speed up the green and help improve the health of your turf.

Aeration should continue, using a mix of micro, needle or star tines which give maximum effect and almost zero turf disturbance.

Regular use of a sarrel roller will be beneficial and the use of micro tines to aerate the green will help reduce soil compaction, 'vent' the root-zone and to allow water to move quickly from the surface and into the root-zone, thus encouraging the turf to root deeper.

Irrigation: Soil and air temperatures usually increase in May, often bringing on the need to irrigate. If soil profiles, particularly sandy soils, are allowed to dry out too much they often become water repellent (hydrophobic), a state when soils can become difficult to re-wet. Often the first areas to suffer on greens particularly crown greens are the high spots on the green. You may need to spend more time hand watering these problem areas.

When you do water, ensure you go to a depth of 100-150mm to encourage the roots to go down to find the water.

Fertilising: On surfaces requiring an injection of growth, a nitrogen source such nitrate or ammonium will be readily available to the plant. Something such as Advanced Generate 12-3-9 +2Mg +2Fe has the benefit of the whole 12% nitrogen source being ammonium which is readily available to the plant in cooler conditions. It also contains a big hit of sulphate at 34% which is an essential element for plant metabolism and amino acid production in the spring. On top of that, it also contains magnesium and iron, which will increase chlorophyll production to maximise the efficiency of photosynthesis as well as harden the leaf cell walls against disease and cold weather stress.

Given other factors such as available nutrition are in place, and air is ubiquitous, the main requirements for plant growth are;

Of those three variables, apart from a small number of tightly controlled growing environments where undersoil heating and lighting apparatus can be employed, turf managers across the British Isles have effective control of one; water. Of the remaining two variables, then at least in the northern hemisphere, one is guaranteed to improve from the 21st December. This is thanks to the suns relentless daily progression across the sky as the earth rotates around its orbit. The third factor however, is the variable most prone to chaotic and unpredictable behaviour, a fickle parameter of which the turf manager has very little control, that factor of course is temperature.

As with any interlinked system all factors must be in alignment for the system to function correctly, if one is lacking the other factors cannot step into compensate and make up for a deficiency. Plants require adequate light, adequate water and adequate temperature for their metabolic systems to function optimally. Systems which then lead to growth, as new leaves unfurl like organic solar panels eager to absorb electromagnetic radiation to fuel a plants energy reactors. Something which at least from the plants perspective is a necessary precursor to procreation in the form of flowers and seed. In the instance of sports turf surfaces we dispense with the procreation aspect (Poa annua aside!) and focus on cultivating steady, controlled leaf growth. Leaf growth which is required to repair the winters damage and regenerate sports turf surfaces into peak condition in preparation for the seasons play.

Cold springs then do few favours for the turf manager as a lack of temperature limits not only the plants ability to react, but also the ability of all the other biological organisms plants so intimately rely on, to mineralise elements for food, or help protect against pathogens, many of which are also lying low in the chilly conditions themselves. There is of course a reason your fridge is set to 5 °C; a cold soil then is a dormant and unproductive soil.

Within a natural system a cold spring isn't too much of a problem of course, things will kick in sooner or later and then catch up. However, for turf managers one factor is bound to cause difficulty; expectation. Expectation of perceived "correct" conditions for the time of year, usually expectations closely aligned to a fixtures list. A fixtures list which was of course arbitrarily fixed without recourse of consultation to the weather, that which is the most chaotic and unpredictable of the master variables required for plant growth.

Tricky times then, and ones which will test the political and communication skills of those seeking to manage expectation; tricky also from an agronomic perspective.

It is not all doom and gloom however, the good news is that the sun continues to rise and progress ever higher up the sky, bringing with it increased daylight and periods of localised warmer intensity on turf surfaces to encourage biological activity. The limiting factor as we enter into April is the effect of the cold easterly air on night time temperatures. It is when night time temperatures dip into single figures that the benefits of periods of warmer sunshine during the day are lost. The result being that the base line temperature each morning starts afresh from a low point, never being able to build momentum into the next day from retained warmth overnight. Consequently the bar for metabolic activity remains frustratingly low.

In this context it is worth reminding our self of how temperature ranges effect growth patterns in the grass plants we are managing.

Grass Plant Growth

1°C

Root growth stops

5°C

Shoot growth stops

10-18°C

Optimum for roots

15-24°C

Optimum for shoots

25°C

Root growth stops

32°C

Shoot growth stops

A soil thermometer is a vital and inexpensive tool for identifying when rootzones are warming up. Such knowledge helps to inform the turf manager on timing of inputs and maintenance work.

Nutrition

As stated, soil temperature is a key factor of growth, one core reason for this is because that is where the food and water gathering parts of the plant and the associated microorganisms reside. Consideration of that fact should lead one to conclude that soil based nutrition is going to be less available through the roots and organic nitrogen sources such as bone, feather meal and urea are not going to be made available (mineralised) by microorganisms. When soil temperatures are low but the sun is growing in elevation and intensity enough to create localised warming of the soil surface for periods during the day time, it is sensible management to optimise those windows and give the plant and microorganisms every chance to work as efficiently as possible in their short spells of warming comfort.

The first part of that process is ensuring that nutrient minerals are balanced in the soil by undertaking a broad spectrum soil analysis which reports result for all plant essential macronutrients and micronutrients. The second step is ensuring that all parameters are within guidelines and a plan is in place to top up deficient soils . In the meantime a good way to overcome soil deficiencies is via foliar application. No one nutrient is more important than the other, they all play an equal, balanced role in plant function and health.

Nitrogen - Whilst soil temperatures are cold choosing mineral salt nitrogen sources such as nitrate and ammonium are the correct options, maximum foliar uptake of applied liquids will peak after 48 hours so try to avoid cutting in this time period and certainly return clippings to the surface.

Chelation - Chelate is derived from the Greek word for claw. Chelates are organic molecules which in simple terms encapsulate a plant nutrient and assist it in being absorbed into the plant. Thus it is recommended to choose liquid feeds whereby the nutrient metals are chelated.

The addition of a high quality humate containing fluvic acid will further assist this process.

Carbon - The base energy ingredient for plants and soil microorganisms, an application of carbon sugar will assist in maximising conversion and uptake of nutrients, as well as stimulating the soil ecosystem.

Scarification and Aeration

Aeration will allow oxygen into the soil which in turn enables many chemical and biological processes however, be mindful that recovery will be slow and protracted whilst soil temperatures are low so narrow tines or slits are preferable.

Moss will be an issue on many surfaces and an application of lawn sand often proves particularly effective in tackling it. However be aware that moss is best treated when moist so avoid application when the moss is drying out. This is because the moss will be entering dormancy and the iron will not have as good an effect, quite a few people were caught out by this in April 2017 and were then disappointed by their level of control.

Similarly to aeration do not be tempted to scarify surfaces to remove moss when growth is sluggish, this only thins the sward allowing weeds opportunity to germinate, not to mention the stress it places on an already struggling grass plant. Scarification should only be carried out when grass plants are actively growing.

Seeding

A cold spring is never conducive to the germination of grass seed, late August and September are the months nature intended this process to take place. Germinating and maturing seed through a cold April is a challenge. So unless you have access to good irrigation to nurse it through warmer days in May and June, it may be worth waiting until later in the year.

Disease pressure is likely to be low whilst temperatures remain unseasonably cold. Keep an eye out on forecasts however, as breaks in the weather culminating in warmer, wetter days may provide windows for fresh outbreaks on scarred areas. Calcium and Seaweed are good non pesticidal solutions at this time of year when applied before disease is active.

Pests

Taking time to create an integrated turf management plan with respects to insect pests is absolutely crucial as proactive solutions are the only available options.

Recording areas affected and planning to apply nematodes during the application window later in the summer helps to prevent badger and bird damage later in the year. The first step is simply remembering to keep and eye out for beetles and crane flies on your site before noting down the date to refer to in later years. Once you have seen adult pest activity project forward the application time for nematodes using the info-graphics on the Pitchcare Shop to aid you.

The first step with respects to chafers is being able to monitor the beetles by deploying chafer beetle pheromone traps onto the site in May and June.

Surfactants

Even though warm hot weather seems a long way off it is important to give adequate time for surfactant chemistry to build up in the soil ahead of stressful periods, prevention is without doubt better than cure. For this reason surfactant applications should continue as per planned wetting agent programmes.

  • Keep machines overhauled and clean.
  • Inspect and repair any watering or irrigation systems.
  • Continue to check and service your floodlighting systems.
  • Replace any worn tines on your aeration equipment.

Our Lantra Accredited Bowls Green Maintenance Course is now available as an online course.

You can learn about maintaining a bowls green in the comfort of your own home and in your own time. This newly developed course consists of a number of videos with assessment questions, and an accompanying hard copy Course Manual. The Online Course is Lantra accredited and provides you with all the basic knowledge required to maintain a green over a 12 month period.

Pitchcare is the only provider of LANTRA accredited training courses in the maintenance of Bowls Greens. More information

We can also arrange Lantra accredited training on site to groups of 6 - 10 people. Email Carol Smith for information.

The Course Manual at just £30 is available for purchase separately.

All Forthcoming Courses.