Deeper Rooting Trials
When we think about a healthy lawn, we naturally focus on what we can see above the soil: colour, density and overall appearance. But much of a lawn’s ability to cope with difficult conditions is determined by what is happening underneath it.
A strong, deep root system can make grass better equipped to withstand drought, heat, wear and periods of reduced nutrient availability.
As our climate becomes more variable, this is becoming increasingly important. Longer dry periods, warmer summers and restrictions on water use can all place additional stress on lawns. That is why grass breeding and selection increasingly looks beyond appearance alone. By studying how different grass varieties develop below ground, researchers can identify grasses capable of establishing deeper, more extensive root systems.
The result is grass that can make better use of the water and nutrients already available within the soil.
Why deeper roots make a difference
Grass roots absorb the water and nutrients required to keep the plant growing. During favourable conditions, moisture may be readily available near the surface of the soil. During prolonged dry weather, however, those upper layers can dry out quickly. Grass with a shallow root system is more dependent on moisture close to the surface.
Deep-rooting grasses can explore a much larger area of soil and potentially access moisture stored further below the surface.
This gives the plant a greater reserve to draw upon when rainfall becomes limited. A well-developed root system can therefore help grass remain healthier for longer during stressful conditions and recover more effectively when conditions improve.
Putting roots to the test: RadiMax
Understanding exactly what happens underground has traditionally been difficult. Grass roots can extend far beyond the small soil samples typically used in conventional testing, making it challenging to compare how different varieties behave under realistic drought conditions.
That is where RadiMax comes in.
Developed through a collaboration involving DLF and the University of Copenhagen, RadiMax is an advanced root-screening facility designed to study how plant roots grow deep within the soil. The facility allows researchers to examine root growth at depths of up to 3 metres while exposing plants to carefully controlled differences in soil moisture.
This provides an unusually detailed view of how individual grass varieties respond when access to water becomes increasingly difficult.
How the RadiMax trial works
RadiMax creates a controlled moisture gradient within the soil. Plants are grown across the facility while water availability gradually changes with depth and position.
As conditions become drier, researchers can observe which varieties are able to extend their roots far enough to continue accessing available moisture. This allows different grasses to be compared under the same conditions. Researchers can then examine characteristics including:
- Rooting depth
- Root mass
- Speed of root development
- Ability to access deeper moisture
- Plant growth under increasing drought stress
- How long grass maintains its green appearance
This information can then be used alongside traditional turf trials to identify varieties with desirable drought and stress-tolerance characteristics.
What RadiMax tells us
The research demonstrates an important principle: not all grasses develop their root systems in the same way.
Even within the same grass species, individual varieties can behave differently below the soil. Some may produce a relatively shallow root system, while others extend much further into the soil profile.
By identifying these differences, grass breeders can select varieties based not only on visible characteristics such as colour, fineness and density, but also on their ability to cope with environmental stress.
That enables us to create grass seed mixtures that are better suited to the conditions lawns are increasingly likely to experience.
Grass varieties verified through RadiMax
RadiMax screening has been used to evaluate several turfgrass varieties, including specialist varieties of tetraploid perennial ryegrass and tall fescue.
FABIAN
Tetraploid Perennial Ryegrass
TETRADRY
Tetraploid Perennial Ryegrass
ARMANI
Tall Fescue
BULLSEYE
Tall Fescue
ESSENTIAL
Tall Fescue
SENCILIA
Tall Fescue
Tetraploid perennial ryegrasses are known for producing relatively large seeds and vigorous seedlings, helping them establish strongly and develop extensive root systems. Whilst the Tall fescue is particularly valued for its naturally deep-rooting growth habit and ability to tolerate warmer and drier conditions.
These characteristics make it especially interesting when developing lawn mixtures intended to cope with increasing environmental stress.
What can a stronger root system mean for your lawn?
A deeper and more extensive root system can provide several practical benefits:
- Improved drought tolerance – deeper roots can access moisture held further down in the soil.
- A greener, healthier lawn – stronger plants can cope better when growing conditions become difficult.
- Better establishment – rapid root development helps young grass plants become established more quickly.
- Improved wear tolerance – well-rooted grass has a stronger foundation for recovering from everyday use.
- Reduced irrigation requirements – grasses that make better use of soil moisture may require less supplementary watering.
- More efficient nutrient use – a larger root system can explore more soil for available nutrients.
- Reduced maintenance inputs – resilient plants can help reduce the need for additional water and fertiliser.
Ultimately, better rooting helps create a lawn that can make more efficient use of the resources naturally available to it.
Products Using Amenity Tetraploid Perennial Ryegrass
