Soil Moisture and Irrigation

Water availability in Soil according to Sensors
The amount of available water in the soil will vary depending on the soil type. A heavier soil can have twice as much available water than a light soil which means that the optimum soil moisture range for a light soil is narrow and rapidly depleted compared to a heavier soil. The hornet monitors the soil moisture across all soil types and plots it on easy to interpret graphs.

Viewing soil moisture levels on the website is easy, a simple graph compares your current moisture levels with high and low set points for the site where the hornet is installed. Armed with this information you are able to fine-tune your run times and frequency to keep soil moisture levels between these set points. This way you are scheduling the irrigation to meet the needs of the turf.

Optimum Zone

Optimum ZoneUsing the hornet graphs you can track moisture and irrigation events and adjust run times to keep soil moisture levels within an optimum range. By doing this you meet the needs of the turf and present a quality surface without excessive water use.

This graph from the hornet shows the set points (upper line for over-watering or full point and lower line for under-watering or stress point) and the soil moisture level tracking between them. The aim is to maintain the soil moisture between the lines. Notice the soil moisture levels dropping below the stress point line indicating the need for additional irrigation.

The optimum zone varies depending on the type of soil and so does the depletion of water.

Sandy Soil

Graph of Sandy Soil
This graph shows the hornet readings for a sandy soil. An irrigation event increases soil moisture levels quickly but within one day it is reaching stress levels. Notice also the low full point and the low level of available water (5mm) in this sandy soil.

Heavy soil

Heavy Soil
Compare the sandy soil above with a soil that has a higher level of organic matter in the surface. The irrigation event took soil moisture levels above the full point of 28mm and took 5 days to reach stress levels. Notice also the higher stress point for this soil and the higher amount of available water (14mm) in this amended soil.

Good Irrigation

Good Irrigation with Soil Moisture Meter
Data from each site is easily accessible over the internet and is simple and easy to use anywhere where you get Next G or 3G mobile phone coverage.

The graph opposite shows good irrigation practice that keep the soil moisture levels in the optimum zone.

Multiple Depths

Multiple Depths of Soil
The hornet measures soil moisture at multiple depths which enables the monitoring of excessive irrigation events.

The red line represents 20cm the blue 30cm and the grey 40cm.

Over Watering

Over Watering Graph by Soil moisture sensor
Bad irrigation practice occurs when soil moisture levels from an irrigation event flows down and beyond the reach of most turf roots.

Notice water is being wasted as the lower sensor detects water indicating it is moving below the root zone.

Water Use

Use of Water Graph by Soil moisture meter
The hornet can even determine how much water the turf is using. The graph bellows shows that 4mm of water was used between 9am and 5pm.