April Maintenance

General Maintenance

As spring renovation will now be well underway, most courses will now look to aerate the greens and get new top dressing materials into the surface so as to restore levels and maintain surface porosity.

You have a choice with aeration as you can go with solid or hollow tine spiking and this will depend on your goals, but the aim is always to get air into the soil profile. Vert-draining with solid tines to a depth of more than eight inches should help the roots chase the moisture down the soil profile and provide the sward with a stronger root system - this underpins the success of plant growth.

Next will come topdressing with a compatible rootzone material. Don't overdo the rate of topdressing as this may smother the sward. What type of sand you use is also very important and most sand sold in the UK is for other uses. As the sports turf market is a small one, be careful if you are offered cheap materials, as they could be finer, a different shape, colour, lime content and be more interpacking than sand which is specialised for sports turf.

The dominant particle range in the sand should be medium sand  - that is 0.250mm to 0.5mm.

Add as much topdressing as you need - the amount will vary depending on what you require. In the spring, you are looking at spreading between half to one and a half tonnes of material per green (that is 2-3mm per square metre). Many are now taking the approach of topdressing every month - little and often.

Your soil analysis will help you determine your feeding programme. With your nutrient levels for greens and fairways to hand you can choose the appropriate fertiliser product for your turf surface. There are a wide range now available which are formulated for healthy grass growth.

Make sure your mowers are kept serviced and are set up accurately. Make sure the height of cut and blade sharpness are spot on.

You should have tested and calibrated all irrigation systems by this time, making sure all sprinkler heads are working and delivering the right amount of water to where it is needed. Calibrate spinklers at least once a year to ensure spray pattern and coverage is sufficient for your requirements. Do this by placing a number of catch cans on your green and then measure how much water is collected. How much water your sprinklers deliver may come as a surprise!

You might need to irrigate during spring renovation because air temperature is increasing and daylight hours are getting longer which can lead to ground and surfaces drying out.

Once these renovations are complete, it is time to start with daily maintenance routines.

Mowing operations will already be in full swing and you will be mowing at different frequencies, weekly or monthly depending on how the grass is growing and what standard course managers set.

Mowing heights will vary due to local conditions, course type, expectations, sward type and mower type. Use the following as a guide and always remember to not remove more than a third of total grass height each time you cut. Stress the grass as little as you can now and reap the benefits later in the season.

Greens: Mow at 4-6mm

Tees: Mow at 10-15mm

Fairways: Mow at 15-20mm

Rough, semi-rough grass areas: Mow and tidy up these areas

Make sure to clean your mower after use (wash down or blow off), apply some WD40 or similar oil-based lubricant to the cutting cylinder after you have washed it down. Keeping the mower clean will make the job of checking cutting heights and maintaining the blades easier.

Change holes regularly, as many as three times a week as a general rule. Exactly how often this is done will be dependent on several factors: green size, construction, tournaments, amount of play and what condition the green is in.

When it is wet, the hole may wear more quickly, causing a crowning effect and surface wear. This wear will show up more if there are any thatch problems with the green. In this case the hole will wear more quickly and form a depression caused by the placement of golfers' feet.


Before the end of spring renovations is a good time to take soil samples and send them off for analysis. Make sure to get a full particle size distribution (PSD) done as this will tell you the actual make up of your soil profile.

All soil contains a percentage of clay, sand, and silt and the PSD analysis will confirm the ratios and confirm soil type to give you a good understanding of what soil you have to deal with. You will also establish the amount of organic matter (OM) content plus soil nutrient status and soil pH. This information helps you identify your soil's needs.

If grass is showing any signs of stress such as weak growth or discolouration continue with fertiliser treatment and tonic in accordance with your annual programme. Most will now be applying a spring/summer NPK fertiliser (12/0/9 or 9/7/7) to effectively get the grass growing this month, then move towards a slow release fertiliser towards the end of the month or early May to get through until June or July.

Precisely what material and how well it works will depend on different factors including soil type, weather. Moisture and air temperature are growth catalysts.

Some are now using compost tea formulations to improve the fertility of their greens. This works by encouraging more microbial activity in the soil and reduces the amount of nitrogen being applied. They are brewed on site and applied each month along with other bio stimulants.

Be careful when applying fertilisers, don't overdose or overlap. Calibrate your sprayers or spreaders and choose the correct nozzles/aperture settings before you begin.

Weeds, pests and diseases

Following recent rain, many courses have suffered in the last six months so most will be a problem everywhere. Traditionally, this is controlled by lawn sand and other cultural practises.

Prevention is always better than a cure or responding to a problem so ensure a minimum of bare areas throughout growing season and keep thatch under control. Moss is an advantageous species so try to ensure a competitive growth habit by individual grass plants. Heading into winter, ground coverage is essential.

But what else can be done to reduce the risk?

  • Ensure adequate irrigation but don't over-water. Plenty of sports complexes use automatic irrigation systems. Water thoroughly, but to requirement, particularly during times of stress as over-watering can lead to other problems.
  • Find a balance with mowing height as mow height affects how the ball plays so your task is to find a level that allows good coverage without adversely affecting playing conditions.
  • Reduce thatch by using controlled frequency verticutting and deep scarification when recovery is underway. That will reduce the organic content within the thatch layer. Limiting this moisture holding ability within the O horizon of the soil is very important.
  • Aerate. This is crucial to provide a competitive grass sward. Mosses prefer compacted, moist soils so reduce compaction and increase drainage ability to deny them the conditions they need to thrive.
  • Remove surrounding causes of shade. In areas where moss is prevalent, try to remove anything that might cause shadows (tree limbs, for example). Moss is highly competitive in shade over grass.
  • Overseed. It is recommended to overseed in the autumn because moisture and mild weather will promote early germination and establishment, key to reducing the chance of moss appearing.
  • Balance your fertiliser programme.

Always strike a balance between the needs of your players and controlling the moss, but the above approach should help you produce excellent quality services - so by implementing solid greenkeeping techniques you should see a reduction in moss.

Carry out worm treatments if they are needed but think about why they are present. pH level, organic matter and cultural practises may need to be looked at.

Repair damage made by moles or rabbits as required and keep an eye out for any attacks of fungal disease, treating with fungicides to treat.

Machinery & Equipment

Make sure your equipment is in good condition and ready for use at all times. Any downtime could be costly so keep on top of this. As the weather improves, you'll be out on the course more and more keeping it in good condition so you can't afford to be missing any equipment.

If you have your own workshop and mechanics then you are well placed to keep equipment in good condition. Others will have to stay ahead of the game and all machinery should have been serviced already and now be ready to use.

Get hold of a good wash down facility as this is an essential tool for keeping equipment clean and a worthwhile investment.

Dennis Mowers