May Maintenance

Key tasks

Growth in the UK will be reaching its peak over the next eight weeks so your focus will be on how often you are mowing, provided the soil has enough moisture in it.

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

Mow your greens three times or more per week and undertake grooming, verti-cutting or brushing on a weekly or fortnightly basis. This will improve air movement and reduce thatch levels building up in the profile of the sward.

The sward will be growing as soil temperatures rise and it is stimulated by fertilisation. Mow regularly to keep the sward height between 4 and 5mm. You can also verticut or groom every two weeks to help speed up the greens and improve your turf's health.

Continue to aerate using a mix of tines for maximum effect and minimal surface disturbance. The greens will benefit from regular use of a sarrel roller and using micro tines will help keep soil compaction to a minimum, 'vent' the root-zone and enable water to move quickly from the surface into the root zone. This will provide the ideal conditions for the turf to root deeper.

As soil and air temperatures tend to rise this month, you will probably need to irrigate. If soil - particularly sandy soil - is allowed to dry out too much, they can become water repellent (hydrophobic) and this makes it hard to keep the soil wet. The first areas to suffer on bowling greens will be the high spots, so spend more time watering these areas by hand if you need to.

Water to a depth of 100-150mm to encourage the roots to go down and find the water.

Thanks to cold temperatures at night, growth is sluggish so your surface may need a bit of a boost. Look for a nitrogen source such as nitrate or ammonium, for example an Advanced Generate 12-3-9 +2Mg +2Fe. This has the benefit of the whole 12 per cent nitrogen source being ammonium, and is readily available for the plant in cooler conditions. It also packs a 34 per cent hit of sulphate - essential for plant metabolism and amino acid production in the spring. Plus, Magnesium and Iron are also included to increase chlorophyll production for maximum photosynthesis efficiency and hardening the leaf cell walls to protect against disease and cold weather stress.


All greenkeepers should now have adopted the important skill of monitoring the performance of your playing surface. Modern technology, tools and a camera will enable you to monitor in a number of ways.

Performance Quality Standards (PQS) have been promoted by the turf industry for many years now as a way of measuring sport pitch maintenance standards. Survey and measure the performance of your facilities to ensure they meet these standards.

Steps to take include measuring or monitoring grass species composition, hardness and infiltration rates of the root zone, levels over a 3m level, soil temperature, sward height, and weed content.

Recently, GPS mapping devices have been developed that measure levels of chlorophyll, moisture content and any change in these levels. Perform soil tests to determine soil type, nutrient status of the soil, organic matter content, CEC capacity and soil pH.

Keep a record of these parameters so you can better understand what is going on with your green and make better decisions to ensure the best possible playing surface.

Weeds, pests and diseases

Prevalent at the moment are leatherjackets and chafers. You can apply Merit if you have it in stock, but with the grubs in their current stage of development, it can be hard to get a good kill.

As the soil temperaure increases, you may spot symptoms of plant parasitic nematode activity. Two categories of nematode infect grass plants. They are Ectoparasitic and Endoparasitic. The former migrate along the outside of roots and feed accordingly and the latter enter root tissues and feed on the plants in these areas.

Look out for the following symptoms: yellow/thinned turf, reduced turf vigour, premature wilt, turf grass slow to recover from stress or respond to fertilisation.

You can use Biomass Sugar to help rebalance the soil and reduce the stress on the plant from the attack.

One more thing to look our for is Microdochium Patch, particularly if warm conditions combine with humidiy and moisture on the leaf for any length of time. Consider systematic fungicides but only as a last resort. If the grass is growing well, the disease could just bubble under the surface and the turf will outgrow it.

Machinery & Materials

Your mower will be now be serviced and sharpened ready for the new season and it is always worth investing in a winter service. Keep checking the condition of your machinery and plan for any repairs or services in the winter.

Keep your machines overhauled and clean, inspect and repair any watering or irrigation systems, check and service your floodlights and replace any worn tines.

Dennis Mowers