Encouraging a healthy sward

Encouraging and maintaining a healthy sward requires a lot of mechanical and physical activities, as well as applying several enhancing products such as plant feed supplements, wetting agents and top dressings throughout the year.

Grass growth is adversely affected by nature in the form of various biotic and abiotic stress factors. Water deficit is one of the major abiotic stresses, which negatively affects grass growth.  During the recent period of hot sunny weather, you most likely would’ve seen the detrimental effect water stress has on our lawns.

Without water, grass soon turns brown, and in extreme cases can die. However, the UK climate tends to prevent this from happening, due to the fact we are a small land mass surrounded by water. Therefore, it is often inevitable we soon see a change in the weather and receive a downpour to revitalise our lawns.

A combination of watering, coupled with a selective weed and feeding regime, will endeavour to keep a sward in a good condition during the summer months.

However, there are several other activities that can be carried out to ensure we can maintain a healthy sward.

The following activities are generally implemented throughout the year to maintain an ornamental lawn to a high standard.

1. Mowing the sward on a regular basis generally twice or three times a week during the growing season (March-October) maintaining a height of cut at anything between 10mm-40mm depending on type of amenity surface we are managing. Mowing frequencies will subside to perhaps once a week/fortnight from November to February 
2. Weed & Moss treatments. Usually carried during spring and autumn renovations 
3. Scarification, removal of unwanted debris. Usually carried out during both spring and autumn renovations
4. Verticutting - thinning out the sward (monthly during the growing season)
5. Aeration, de-compaction of soil, improving air and gas exchange in soil. Generally carried out during spring and autumn renovations
6. Top dressing, restores levels and improves surface drainage. Generally carried out during spring and autumn renovations.
7. Overseeding, restores grass populations. Generally done during spring and autumn renovations
8. Fertilising, provides nutrients for grass growth. Every 4-6 weeks March -October
9. Watering/Irrigation. As and when required
10. Weed pest and disease control - we have a range of chemical control products available to assist with these issues.

End-of-season renovations are generally carried out towards the end of the growing season, which is late September to early October, and include the following works.

Weed control

This may be dealt with prior to the renovation. Any accumulated moss growth should be dealt with by applying an approved moss-killing chemical. Once the moss has died, remove it by scarification.

Then, mow the sward as short as possible to remove unwanted growth prior to scarification. Scarify the lawn in three directions collecting all the debris.

 

Scarifying

Scarifying is a mechanical/hand method of removing unwanted vegetation that builds up within the sward profile. The process usually involves a raking/cutting action to clean out thatch debris in two or three directions and removing the debris to leave a clean surface. 

Aeration:

Aeration is a key part of a renovation programme. Aeration can remedy any compaction problems by restoring and improving air movement in the soil profile.

 

Topdressing:

The application of a good quality top dressing, usually a 70/30 mix of soil and sand, provides a good topdressing medium to help restore levels and provide a seedbed for any new seed applied.

Benefits of top dressing:

• Restores surface levels.
• Stimulates new root and shoot growth.
• To cover seed (soil seed contact to initiate germination).
• Increases water holding capacity of the soil.
• Improves soil structure.
• Increases nutrient retention.
• Improves surface drainage.

 

Overseeding:

To re-establish grass cover, it’s essential to overseed the area with new grass seed. Choosing appropriate seed is more cost-effective than using cheap or old grass seed stock. Germination and establishment are likely to be poorer when using old seed.

As a rule of thumb, sowing rates will generally be about 35grams of seed per sq/m, but most seed suppliers will also have their own recommended rates. Temperatures above 12°C, a moist, well-aerated seedbed, close seed/soil contact are primary requirements for rapid grass seed development.

 

Fertilising:

Prior to applying any fertiliser, it’s often good practice to have a soil nutrient and pH test done to ascertain the status of the soil. A solid analysis laboratory can analyse an soil samples you take, and provide a profile of the nutrients in the ground. Once you have these relevant results, you can then tailor your nutrient requirements to optimise nutrition.

Fertilisers can be supplied in granular or liquid form, and come in set NPK ratios. Generally, a spring and summer formulation would typically be a (9:7:7) NPK granular product, which you would apply every 5-6 weeks.

 

Watering

Adequate water must be available from seeding through to completion of germination. Try not to allow newly overseeded areas to dry out once watering has commenced. With temperatures still in double figures, seed will germinate between 7-15 days.

 

Conclusion:

Sward renovations are often a time-consuming and expensive exercise, but well worth the effort and cost with the rewards resulting in a newly revigorated lawn.