In this blog we look at how to choose the correct topdressing for your sports pitch, with questions like what and when to apply and much more. There are also six frequently asked questions l tend to come across, like when is the best time of year to topdress and how do we choose a topdressing material. Over now to Andy Spetch who assisted putting this blog together.
I worked for British Sugar for over 35 years. I started in 1987 as an agricultural trainee and worked for the company as an agronomist in England and Poland before taking over the management of its topsoil business in 1997.
I was a keen rugby player and coached when my playing days came to an end. I then volunteered as a groundsman at my local National 2 Rugby Union club, Bury St Edmunds. I am a volunteer pitch advisor for the RFU and a GMA Board member.
What is top dressing?
It is the application of a sand or blend of sand, silt, clay, and compost to an established lawn or playing surface. The exact composition of the dressing will depend on the purpose and the type of surface on which it is to be used.
Reasons why we top dress
- To restore a level playing surface
- To protect newly seeded areas and to encourage germination
- To control and reduce the amount of thatch (OM) in the rootzone
- To improve grass health
- To repair divots
- To increase soil aeration
- To improve surface drainage
- To improve drought tolerance
- To improve drainage
- To top up drainage runs
When & how to apply top dressing topdressing
In a sports turf environment, topdressings are traditionally used at the end of the playing season as part of the annual maintenance programme. Some clubs/venues, however, will top dress on a more regular basis throughout the season to repair badly worn areas and/or to improve the drainage in specific areas. Application of a topdressing can be carried out by hand or machine depending on the size of the area to be treated.
how to choose the correct topdressing for your sports pitch
Selecting the right topdressing
Firstly, establish why you are topdressing and what result do you want?
Do you want to primarily improve surface drainage? Use a high sand topdressing
Do you want to improve surface drainage and the health of the turf? Use a sand / soil topdressing
If you are topdressing to top up the levels of sand slits or drainage runs then it is important that the same sand as used in the slits is top-dressed.
Sand V soil-based topdressings
Looking at sand versus soil at a basic level:
Sand is inert, chemically inactive and incapable of holding on to nutrients or moisture because of its large particle size and positive charge.
Soil, on the other hand, which is a mixture of sand, clay, and silt, is negatively charged, which causes it to attract and retain nutrients such as potassium, phosphorus, and magnesium, plus many micro-nutrients. The clay particles also hold onto moisture.
The cost of inorganic fertilizers required for sand-based dressings is constantly rising and using peat-based composts within high sand/compost dressings isn’t ideal, bearing in mind the necessary focus on climate change. Soil-based topdressings, on the other hand, have a natural nutrient base and, in drought conditions, the soil content improves moisture retention, which in turn reduces turf stress and speeds up the growth of new grass across repaired, high wear areas such as goal mouths.
Typical rates of application
- Rugby/Football – 50 t to 100 t/pitch
- Golf Greens – 15kg/m2
- Fairways and lawns – 10kg/m
For best results a topdressing should be applied as part of a routine maintenance programme during and at the end of the playing season. A good maintenance programme should include fertiliser application, aeration, and over-seeding.
For more advice contact the GMA pitch advisory service:
Products from British Sugar TOPSOIL
Sports & Turf
STRI tested Sports&Turf is ideal for use as a dressing on soil-based winter sports pitches.
The mix of 90% predominantly coarse to medium sand and 10% topsoil improves soil fertility
The nutrients naturally contained, within the silt and clay, will sustain healthy grass growth
This STRI tested sand and soil mix is ideal for repairing high wear areas such as goal mouths and skill training areas
The mix of 80% predominantly fine to medium sand and 20% topsoil means that when applied Sports10 will stay in place and wont kick out like high sand compost dressings.
The nutrients naturally contained, within the silt and clay, will sustain healthy grass growth.
1-How can a groundsperson test if a new type of topdressing is likely to be compatible without his existing soil type?
Most accurate way is to send samples of your existing soil type and proposed dressing to the STRI for a Particle size and Hydraulic conductivity analysis
2-What should a grounds man be looking for in terms of what is deemed a good topdressing material?
Fully analysed. The sand particles within the dressing are predominantly coarse to medium in size and their shape is sub angular to rounded
3-I have seen clubs using high organic material for top dressing such as mulch and also fine builders’ sand, can you give some details on whether these are suitable and why not?
Organic matter alone will tend to hold onto moisture, so do the reverse of what is needed. Organic matter can also dry out and blow away Sand with too many fines in it can capped (form a crust on the surface) block the air particles in a soil profile and slow down the rate of surface drainage.
4-When is the best time of year to apply dressings and what’s the key to applying outside these periods?
Best time is with end of season renovation. I like to aerate; over-seed then top-dress. I find that the topdressing covers the seed and aids germination. This can be followed by a mid-season topdressing if budget and weather allows.
Would always aerate before topdressing, the topdressing will go down the holes created by aeration. Brushing post application can also help with the integration of the topdressing into the topsoil.
5-I see topdressing grants are now available via the FA is this something your becoming aware clubs are accessing?
Yes, I am seeing and reading that more clubs are seeing the benefits of topdressing.
How to Choose the Correct Topdressing for your Sports Pitch by Andy Spetch
If you found this helpful, why not check out this blog on things you need to know about grass seed pre renovations – https://turfcareblog.com/13-essentials-things-to-know-about-grass-seed-prior-to-renovations/