Expected weather for this month:

Warm and sunny weather

It is surprising how quickly soils can dry out once temperatures rise into double figures, and the sunny warm weather we had during April certainly increased evapotranspiration rates, leaving the soil and plants requiring water to replenish their reserves.

The combination of drying winds and bright sunshine soon increases the need to water your bowling green. Most clubs will hopefully have the means of watering, whether it be by hand or by fully automated pop up watering systems. The key to using both is to ensure the soil profile is watered enough to cope with the evapotranspiration rates (amount of water lost), which on a warm day can be as much as 6mm per day. Crown greens will be more susceptible to drying out, so hand watering may be required to wet up the crown.

For clubs whose greens are drying out, it may be a sensible option to raise the height of cut to help the grass plant tolerate these extreme dry periods. Just raising the height by 1-2mm will help.

For clubs with watering facilities, however, ensure you keep the green watered and that you water to a depth of 100-150mm to encourage the roots to go down to find the water. With air temperatures in double figures, grass growth is going to be fairly vigorous, requiring you to mow your grass more frequently.

Most clubs should now be looking to mow their greens more frequently, at least three times a week and, depending on resources available, should even consider mowing on a daily basis. All pre-season fertiliser applications will have 'kicked-in', with key playing surfaces becoming smoother and more consistent following spring topdressing work.

Key Tasks for May


bowls green donnington and lg 012.jpgFor the next eight weeks or so, UK growth reaches a peak, therefore the emphasis will be on mowing frequency as long as there is sufficient moisture within the soil. With daily mowing at around the summer averaging at of 4-5mm, there will be a need to supply the turf with a 'little and often' foliar feed, consisting of mainly Nitrogen, with other nutrients and ingredients, such as Potassium, added to the mix as required in order to meet the turf's needs.

Seeding sparse or bare areas can be continued. Any rise in soil or air temperatures will help germination. Use germination sheets to aid this process but remove the sheets regularly to check for diseases.

Remember that without good seed to soil contact, the operation is useless. Ensure you use new seed as old material may not give you the required germination rates.

Greens should be mown at least three times a week, with some grooming/verti-cutting or brushing being undertaken on a weekly/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.

With the development of mowing technology, most fine turf mowers have cassette fitting attachments that offer additional maintenance operations such as grooming and verti-cutting. These are both operations that effectively remove thatch and side shoot growth enabling the promotion of an upright plant and denser turf growth.

Some clubs now use turf irons (rollers) to prepare surfaces for play, these are specially designed ride on turf rollers that apply even pressure over the surface. However, rolling can have a detrimental affect on your turf if done at the wrong time or too often. There will be a need to increase the frequency of aeration techniques to counter balance the practice of rolling.

Aeration should also 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.


May is also a good time to apply fertilisers, wetting agents and soil conditioners.

There are plenty of choices of fertiliser to use. See Pitchcare store for a range of products that can be applied in both granular and liquid formulations. A soil test should ideally be done to ascertain you needs. However, there is a vast number of spring and summer ones that will meet your needs.

Also be aware of other factors that may influence the performance of the green, many club greens are surrounded by hedges and trees which can cause shading problems. Reduced light levels, lower soil temperatures and restricted air movement will also affect grass growth.

Most greenstaff will have already applied a spring/summer fertiliser, perhaps something like a 9+7+7 and will be looking to apply a summer fertiliser, reducing the N and P inputs to maintain a balanced growth during May. At the end of the month, an application of a slow release fertiliser will see you through June and July.


Bowls1.jpgSoil 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.

However, the long term affect of drying greens could be detrimental to surface playability. The surface could begin to break up, particularly on sand predominant greens. Sand becomes unstable when in a dry state and the surface can become bumpy. Different grass species will respond differently under drought conditions, growth rates will vary depending on habit and root structure, thus promoting an uneven surface.

Once the soil goes beyond a certain drying stage, you are likely to encounter dry patch symptoms, whereby the soil becomes hydrophobic, being unable to absorb water. The water simply runs off instead of soaking into the soil profile.

Water will also always wash off from the high spots into the low areas, so the low spots tend to remain green and lush. This variation of dry and wet areas will affect surface playability, the bowls will fly across the dry areas and slow down on the lush green areas.

Once soils become hydrophobic, they can deny adequate water movement to other areas of the rootzone - often resulting in water deficit stress with symptoms that include a general decline in the biological health of the plant which in turn effects shoot and root growth.

You may need to consider using wetting agents to aid recovery or help prevent these problems occurring in the first place. Many greenkeepers now utilise wetting agents on a monthly basis to keep the rootzone in good condition.

The movement of nutrients in the soil is also dependant on the moisture state of the soil; dry rootzones will slow down or even prevent nutrients being assessable for the plant. Which, again, will result in plant health decline.
If you do not have adequate watering facilities, it may be beneficial to raise the height of cut by 1mm to keep a bit more grass on the green during these dry periods. It may slow the game down a bit, but will help sustain your green through these difficult times.

It is important to water correctly; under or over watering will have a detrimental affect on plant health. You need only to apply enough water to replace what has been lost by evapotranspiration. Depending on the aspect of your green, soil type and herbage cover, you could be losing anything between 3-5mm of water per day. This will need to be replaced by watering.

It is important to ensure you water evenly and to depth, you want to ensure the water gets down beyond the rooting profile at least between 100-150mm. This will encourage deeper rooting as the green dries and the roots go in search of the descending water.

Also check your water quality - what pH is it? Is it suitable for your green? Check filters on recycled water systems. Poor water quality will affect plant growth and sustainability.

Monitoring the performance of your playing surfaces is a key skill that should be adopted by all Groundsman/Greenkeepers. With the aid of modern technologies, tools and a camera you can now monitor the performance and the condition of your sward in many ways.

For many years the turf industry has promoted the use of Performance Quality Standards PQS to ascertain the standard of sport pitch maintenance.

It is important to survey and measure the performance of your facilities, with modern technologies we can now measure all manner of aspects of the pitch/golf green or artificial pitch to ensure it meets any stated guidelines by the sports governing bodies.

These can include measuring sward height, composition of grass species, soil temperature, weed content, levels over a 3m level, hardness and infiltration rates (porosity) of the soil rootzone.

In recent years we have seen the development of GPS mapping devices that can measure, chlorophyll , moisture content and deviation in levels. Soil tests will also help determine soil type, nutrient status of the soil, organic matter content, CEC capacity and soil pH.

Keeping a record of these parameters will help you have a better understanding of what is going on within your playing surface and enable you to make better decisions on what maintenance inputs you will need to undertake to maintain surface playability.

Regular brushing and sweeping are important tasks to keep the surface clean, open and dry. A dry surface will aid resistance to disease. Keep an eye on fungal disease attack and use approved fungicides to treat infected areas.

A selective weed killer will help control any broadleaf weeds, the timing of application is key, apply when weed growth is vigourous.


Pitchcare is the only provider of LANTRA accredited training courses in the maintenance of Bowls Greens. It is a one day course designed to provide a basic knowledge of bowling green maintenance. The course enables the Groundsman to grasp the basic needs of a bowling green surface, either Flat or Crown, throughout a 12 month period.

Delegates attending the Bowling Green course and using the accompanying manual will be able to develop their own skills, working knowledge and expertise, by understanding the method of instruction and the maintenance principle it sets out.

Included in the Course Manual, there are working diaries showing the range of tasks needed to be accomplished each month. The Course Manual is available for purchase separately.

In addition, we are able to arrange courses to be delivered on site to groups of 6 – 10 people. Email Chris Johnson for information.

Perimeter fences and hedges: Most bowling green facilities are enclosed by fences or hedges and April is a good time to complete any tidying up of these features. Be mindful that birds will be nesting in hedges so do try not to disturb them during this time.

Repairs: Carry out any repairs to ditches, paths, gates, floodlights and other building features. Ideally, you should have your floodlights serviced on an annual basis to check that they are safe and operating to the correct lux values, making sure to also check that the lights are correctly positioned thus preventing unwanted light pollution.

Products & Articles