June Maintenance

Key maintenance tasks this month

As you will be mowing more and more, alter your direction of cut and cutting patterns to ensure turning circles don't place unnecessary stress and there is no grass 'napping'. Make large turning circles where you can or even resort t three-point turns.

You will need to do heavy divoting on tees, fairways and surrounds as more and more play is taking place. The weather getting warmer and sporadic rain showers will help germination and establishment. Renovate any bare areas to reduce any potential levels of weed/poa invasion as the growing season continues.

As the sun comes out and the temperature rises, more people will be on the course. Pressures to produce the best possible conditions are constant but remember that aerating and topdressing little and often is the way to go. When it is warmer and drier, do not use tines that will leave large holes such as slit tines as the hole will not be able to recover fully in these conditions.

You will be using irrigation systems more often now due to the weather. Make sure your pop-ups and central systems are working as they should. Clean the system and make sure the sprinkler arcs are properly positioned. Trim around the pop-ups and valve boxes to increase the speed of work during the morning and aid presentation. The pop-ups should be used when surfaces need moisture rather than applying at set intervals. Check your water quality, find out what pH it is and if it is suitable for your greens. Make sure to check filters on recycled water systems as poor water quailty will affect plant growth and sustainability.

You could be mowing between daily or twice a week depending on the growth of the grass and the standards expected by the course manager. Mowing heights will vary depending on conditions locally, the course type, expectations, type of sward and your mower. Mowing heights listed below are a guide and will change in line with local weather conditions and always remember never to remove more than a third of total growth in any one cut. Place as little stress as you can on the grass at this time and you will reap better results later in the year.

  • Greens: mow at around 3.5-6mm
  • Tees: mow at around 10-15mm
  • Fairways: mow at around 15-20mm
  • Rough/semi-rough grass area: mow and tidy up these areas

Change the positions of the holes regularly although exactly how regularly will depend on green size, construction, condition, tournaments, and type of play. If it is wet, expect the hole to wear more quickly whic will result in a crowning effect and some surface wear. If the green has thatch problems, the wear will be all the more apparent. The hole will wear quickly and a depression will be formed by the placement of golfers' feet. As a guide, most courses will now be changing their hole positions thrice weekly.

To maintain surface levels preparation, light topdressings of sand/rootzones are essential and it is again advisable to go with 'little and often'. Continue to aerate and use a mix of micro, needle and star tines to give maximum effect and minimal surface disturbance. You could also consider sarel rollers but what you are trying to achieve here is to 'vent' the rootzone and provide the right conditions for water to move quickly fom the surface into the rootzone and encourage the turf to root as deeply as it can.

Continue fertiliser and turf tonic treatment if you are doing so and if you haven't got a fertiliser programme get your soil tested, ideally by an independent soil analysis company for impartial and unbiased results.

Standard practice would have been to have applied a spring fertiliser dressing in March and depending on the weather, and what type of greens you have, to apply or be thinking about applying another dressing of fertiliser to keep growth balanced. Reduce the nitrogen (N) and phosphates (P) inputs and apply a 9+7+7 NPK fertiliser or similar.

Many greenkeepers apply a programme of base feeds which they top up with liquid fertilisers. As a general rule, USGA sand based greens are very hungry for fertilisers compared to pushed up soil greens. You can use straight compound fertilisers that act straightaway. These have an advantage over slow-release fertilisers that can activate or stimulate growth when it isn't needed.

Colour up the greens by applying iron and seaweed products before tournaments and events. Some have recently started applying compost tea formulations and topping up with tonics and seaweed extracts but whatever you choose to apply, make sure your feeding programme is balanced and geared towards maintaining plant health.

What you choose and how well they work will depend on factors such as soil type and weather, keeping in mind that moisture and air temperature are catalysts for growth.


June will see levels of grass growth at their highest point of the year. The obvious result here is a lot of mowing but also an increased requirement for essential nutrients. Monitor playing surfaces closely for any sign of nutrient stress and make choices on what fertiliser to use based on the results of your soil sample results from the spring. The increased grass growth may have also exacerbated thatch build-up so take steps to combat this.

Apply SeaAction seaweed and BioMass regularly to supplement your feeding programme as this boost plant function, stress tolerance and soil biology. Use liquids to supplement granular feeding programmes at specific times, like for example just before a tournament or between maintenance operations.

There may have been some red thread around but simply feed this out with a small dose of nitrogen rather than applying a fungicide. As it is a superficial disease on the leaf, it does not affect the crown and won't kill the whole of the plant like other diseases do.

You will likely be busy with moisture management this month. Some greenkeepers now have weather stations at their disposal so they can stay informed about potential evapotranspiration rates within the sward. Don't let the soil get too dried out and keep your watering practices as natural as possible.

Soak the playing surface every two or three days rather than rigidly watering at a set time every day. Get hold of moisture meters so you can find out exactly what is happening beneath your feet.

Get a headstart on any dry patch by using a wetting agent. Prevention by applying now when the soil is moist is much preferable to trying to cure when the soil is dried out, baked and potentially hydrophobic.

Keep an eye on playing qualities, or specifically Performance Quality Standards (PQS) that that the industry promotes and aesthetic qualities within the sward. Many factors could hinder your attempt to meet standards on the putting or playing surfaces.

Record your findings so you can compare results with previous years and check practical elements such as consistency and height of cut so you fully understand every element of your course. Use macroscopes and prisms and any other tools available to give as much insight as possible.

Weeds, pest and disease

Weed growth is always vigourous at this time of the year and you will need to use selective herbicides to get rid of them. These are most effective when the growth is at its most active and remember to always follow the guidelines from the manufacturer.

Moles and rabbits could be causing damage so carry out repairs as and when required.

Watch out for any attacks of fungal disease and any infected areas must be treated with approved fungicides. Once grass growth starts to dominate any scarring will disappear which lessens the need for fungicides to be applied. You might still want to apply a preventative fungicide treatment as you build up to important events or tournaments.

As above, use a small dose of nitrogen to deal with red thread.

Chafer grubs and leather jackets may have been a problem recently and if so think about biological control methods, such as nematodes, at the right time of year. Now may not be the optimum time, for example.

Machinery & materials

Inspect and clean your machinery daily and after each use and make sure any damaged machinery is serviced and repaired.

On a monthly basis, estimate and order seed, loams and fertilisers as wel as fuels and other consumables.