Bowling Green Maintenance: 17. Fertiliser Application 
Fertiliser application will be minimal for most bowling greens if a firm surface is to be produced with the desirable grasses of red fescue and browntop bents.
Do not worry about creating a lush green coloured sward as this will result in a slow game and an increase in undesirable annual meadow which will further increase thatch depth and reduce the quality of the playing surface.
Turfgrasses will naturally be less green during drier summer periods, so be careful not to try and force unnecessary growth which will also increase the potential for disease attack.
Whilst it might be visually pleasing to play on a deep green coloured surface, during the summer period a lighter green colour will provide a more natural look for that time of year. Forcing the plant to be greener will typically involve additional resource inputs, especially fertiliser, water, mowing, scarification and fungicide applications.
An improved colour appearance will please many bowlers, however, at what additional cost? This question is often ignored. One of the commonest complaints from bowlers on flat greens is the lack of speed or draw from their delivery. Clubs should review and reflect on their maintenance programme: Less material input in particular can often (but not always) provide more quality on a bowling green; so less can sometimes be more.
A range of fertilisers might be considered, but a programme based, but not dependent, on organic content with inorganic sulphate of ammonia can help create the conditions more suited to red fescue and browntop bent. The use of controlled release and liquid or foliar feeds can also be considered as component parts of a fertiliser programme.
Before deciding on a programme ensure nutrient release rates and their effect on soil pH, as well as potential impact on disease and weed incidence and grass composition are considered. The inclusion of sulphate of iron with several of the applications, especially in spring and late summer, can help to suppress moss growth, provide some degree of resilience to potential disease attack and also produce a deeper green colour to the sward without contributing to lush growth.
A typical fertiliser (mini-granular) programme for the majority of bowling greens might be based along the following lines:
• Mid-March ‘false spring’: 1-2 g/N/m2 (Inorganic only).
• Mid-April: 4 g/N/m2 (Inorganic and Organic).
• Mid-June: 3 g/N/m2 (Inorganic and Organic), or a liquid feed.
• Mid-End August: 3 g/N/m2 (Inorganic only).
This would give an annual Nitrogen input of 11-12g/m2, which would sit towards the lower end of recommendations for many bowling greens. For soil rootzones this is 8-20 g/N/m2, whilst for sand-dominated rootzones it is 24-30 g/N/m2. (Lawson, D.M (1996) ‘Fertilisers for Turf’, STRI, p.34).
The use of one or more liquid feeds, instead of using a mini-granular feed, during the playing season is often considered. This is primarily to reduce the potential of the fertiliser not being adequately watered into the green and also to reduce the potential impact some mini-granular fertilisers might have in irritating the skin on some players hands.
The phosphorus and potassium inputs would depend upon soil analysis and also the current condition of the green. If phosphorus is required, then typically a spring or late summer application when seed germination following overseeding has been carried out or when root development is more likely than during the mid-summer period when root growth is typically diminished when compared with leaf growth during this period.
The majority, with at least 60%, of Nitrogen is typically applied before mid-June, and no controlled slow-release, particularly if based on IBDU, after this time as well. The main reason being that autumn growth will be softer, nitrate leaching potential can increase, and the green will be more susceptible to disease, especially fusarium patch. (Adams, W.A. & Gibbs, R.J. (1994) ‘Natural Turf for Sport and Amenity: Science and Practice’, p287).
Early spring can be a particularly challenging time for the grass plant. Soil temperatures can vary significantly year from year, and this also applies to the water content of a rootzone. Changing climate patterns are having a large impact on a greenkeeper’s ability to determine the optimum time for fertiliser applications.
Applying a fertiliser that gives a relatively quick response, usually as a granular, liquid or foliar feed, will often be needed when prevailing weather and ground conditions are outside of what has been planned for and a slight ‘tweak’ is needed to the planned programme. The classic ‘false spring’ is an example of when a light application for a short-term quick response may be needed to help develop the sward prior to a main spring application.
Granular fertilisers can then be used as a core component of the main planned fertiliser programme and these will often provide a greenkeeper with more control over nutrient release, supplying extra where needed, because they do not have as long a release period as a controlled release fertiliser. However, by contrast, a controlled release fertiliser might be considered as a follow-on fertiliser in later spring and can reduce the need for more frequent applications as would occur with typical granular fertilisers. If excessive release occurs due to weather conditions, then supplementary granular or liquid applications can be given. There is no ideal situation, and a greenkeeper will decide what is best for their course based on prior history of usage, new products and technologies, as well as cost-effectiveness related to quality achieved for their course.
Autumn can also be deceptive, with warmer conditions still encouraging fairly active growth. However, with growth and development relying on photosynthesis, the light levels naturally drop off quite significantly during this time. Great care needs to be taken not to encourage growth just because the impression is that growth needs to still be enhanced, but this can often just be considered as being a final natural spurt before winter dormancy or ‘taking stock’ by the grass plant.
Only a very low level of applied nitrogen, if given at all, would typically be needed in the autumn, so be careful not to contribute to any forced growth as this will increase susceptibility to Microdochium (Fusarium) and only encourage and strengthen annual meadow grass. If the aim is to produce a high quality well-paced, true and firm surface with a fescue / bent sward, which is relatively resistant to disease attack and annual meadow grass invasion, then great caution is needed with any fertiliser applications after about August to early September for many greens.
Determining how soon or late an application might be used will depend on various factors, but the south of England will typically see later or earlier applications than the rest of the UK.
Even with a changing climate and extended growing season, artificially encouraging growth would not be desirable, especially as light levels (which is essential for photosynthesis to take place) continue to reduce as normal over the autumn and winter period.