When is topdressing a lawn necessary?
In most cases top dressing is done to correct poor preparation and lack of soil underneath or to fill in low spots and correct uneven areas in the lawn. If your lawn is well fertilised, healthy and even, then you don’t need to worry about top dressing.
It isn’t necessary to top dress annually, in fact, regular topdressing can accelerate the build-up of thatch in your lawn.
How does top dressing help a lawn?
Top dressing brings many benefits to a lawn that is looking a little lacklustre, including helping to reduce the accumulation of dead grass clippings and stems, known as ‘thatch’. It helps to increase nutrient retention, improves drainage and increases disease and pest resistance.
When is the right time to top dress your lawn?
Should only be done during the growing season (this is when you need to mow your lawn weekly). The earlier in the season the better. Generally late spring to early summer is best.
What soil should I use to topdress my lawn with?
The soil you use for depends on your reason for topdressing. If you are topdressing to level out unevenness or fill in holes, a fine washed or screened sand is great – it is easier to level. If you are top dressing to improve your soil profile with nutrients we recommend to use a soil/compost mixture.
Fertilise; before or after top dressing?
The recommendation is to fertilise the lawn a week to two before applying a top dressing regardless of whether this is for nutrients or to repair holes or an uneven lawn. This boost to the lawn plant’s growth will assist the turf to push through the dressing more easily and quickly. What you should do after top dressing is to water your lawn. Water just after the application and then maintain regular watering to give the lawn plants a boost after what is a stressful process for them.
Topdressing to improve soil profile
This type of top dressing application places a thin layer of organic soil mixture over the area of your lawn and adds organic, natural nutrients and minerals. You would apply a top dressing for nutrients if your lawn is in need of a boost as it will encourage the production of new shoots and result in a thicker lawn with the added benefit of then hindering moss and weed infestations. The aim is to promote a healthy root system that will protect the turf from weather conditions such as droughts and winter frost.
Topdressing to improve levels
If the area of lawn requiring evening out is only slightly uneven then you can apply a top dressing up to 12mm at once. For areas that are deeper than 12mms apply one layer of 12mm first and then add another layer.
For the repair of a hole deeper than 5cms use a shovel to raise the grass on top of the hole, place top dressing material underneath to elevate the level of the lawn. Then apply the top dressing to address any remaining unevenness.
How to top dress a new lawn
On new lawns top dressing is generally not required, but can be done to fill in any gaps or holes. However we recommend that you leave it for a few months and most of those issues will take care of themselves. Occasionally after a settling period some areas of a new lawn may need a slight correction to desired levels.
Bags of top dressing mixtures are readily available from lawn care centres and nurseries and provide all the relevant handling and application information.
Work out the size of your lawn before you buy; as a general guide a 2kg bag will be enough to top dress a square metre of lawn.
How to top dress:
- Fertilise a couple of weeks prior to top dressing to ensure maximum growth at the time.
- Use river sand or a top dressing soil mix. Using a higher proportion of organic material for sandy soils is a good idea.
- If your lawn is established, first mow low with a rotary mower equipped with a catcher.
- Aerate or core your lawn
- Spread the mix evenly over the desired area
- Rake and level lawn or broom it into the lawn profile.
- Rake in a figure eight motion so that the top dressing mixture is spread evenly.
- Hose the lawn thoroughly so that the dressing is barely visible.
Never top dress more than 1cm in a single application, making sure the grass tips are still exposed.
We hope that these top dressing tips will help you to get the best out of your lawn!
If you have any questions, please don’t hesitate to get in touch with our lawn consultants.