Finally, Know and Understand What your Crop Knows!
Many greenhouse growers encounter plant nutrition problems that affect plant quality and profitability. Often times after finding a problem it’s too late! That’s because their focus has been reactive instead of proactive…to have a soil sensor at the root zone of the plant and automation software to prevent problems is a critical advancement for Greenhouse productivity and crop success. Having multiple soil sensors at the root zone of your crop means you will better understand what they are looking for in the way of nutrients.
What are you Measuring at the Root Zone?
- Conductivity (EC)
The EC of the soil solution, irrigation water or fertilizer solution is an important condition affecting the root zone environment of your crop. Any of these factors can have a significant effect on plant growth, quality, and overall yield. The easiest way to monitor salinity is by measuring the electrical conductivity (EC). EC is strongly correlated with the nutrition of the soil content.
EC measurement is also affected by temperature and, to a lesser degree, by soil moisture content. Typically, measuring nutrition levels have been cumbersome, time-consuming and could possibly damage the plants. Now there is a better, more accurate technique and one that growers can easily adopt. The GS3 Ruggedized Soil Sensor easily measures plant nutrition deficiencies which can be used to trigger an irrigation from our software resulting in quality crop production 24/7.
Soil moisture and its availability to support plant growth is a primary factor in farm productivity. Too little moisture can result in yield loss and plant death. Too much causes root disease and water waste.
Just as important, water is a delivery mechanism for any nutrients that are not tightly bound to the soil. Whether these nutrients are delivered to the field through the irrigation system or through other means, movement of water within the soil governs how they are delivered to the plant roots. Good water management is important within itself, but good water management also means good nutrient management.
Precise control over the root zone environment, in terms of both water and nutrient content, leads to healthier crops and higher yields. The techniques described in this publication can help you gain control over the root zone environment by making measurements, observing trends over time, and using this information to make irrigation decisions. If applied correctly, the results can be significantly increased productivity and reduced cost.
Root zone temperature is also an important factor in learning about plant health. Greenhouses that provides heat directly to the growing media rather than heating the air of the greenhouse can see a triple benefit for their crops: faster production, resilient plant health, and energy savings.
If the root zone temperature is maintained at the optimum levels, the air temperature in the greenhouse can be lowered 5 to 10 degrees F., reducing heat loss to the outside and therefore, reducing energy consumption. This is possible because root zone temperature is more critical than leaf temperature for achieving good plant growth. We utilize a hot water program to maintain heat levels within the growing medium.
Substrate Moisture Sensors & Root Zone Monitoring Program
New Fertigation Manager™ Program for Soil Substrate
The Soil and Substrate Moisture Sensor program measures moisture, E.C., and temperature in soil or substrate growing media. This is a great way to finally manage large water and fertilizer costs. The program also ensures your crop receives the right amount of nutrients and stays in optimum growing conditions.
The Fertigation Manager™ program allows you to connect up to 20 soil or substrate moisture sensors, averaging out readings between three sensors per irrigation zone and it can also trigger an irrigation cycle based on low moisture readings or an E.C. set point in the software. You can connect a maximum of 20 moisture sensors per system and control up to 48 irrigation valves. With greenhouse automation this advanced you can relax knowing that your crop has what it needs to be top quality.
If for example, the EC readings in the substrate bags are too high you can reduce the fertilizer feeding on the next irrigation cycle to flush out unwanted fertilizer salts in the grow bags.
If for example, the temperature is too high in the growing media, you can switch to a lower temperature water source or turn on a water chiller to cool the water.
The wireless sensor controllers are strategically placed through out your crop with remote monitoring with our fertigation software so that it can monitor the root zone of the crop and take care of any deficiencies.
Sensors used to control irrigation, temperature and E.C. can help to optimize plant growth, reduce labor requirements and decrease insect and disease problems
Closed Loop Greenhouse Automation
In Greenhouse Magazines article entitled Growing Better Crops with Sensors, the article informs growers about the benefits of running a closed loop system with greenhouse sensors. Read this section from the article below…
Although most greenhouses already have incorporated a certain level of automated environmental- and irrigation-control technology, they have to have proper installation and systems operations in order to reach their full potential. Advanced sensing can be used to not only reduce labor requirements but also improve plant quality.
An automated control system can be either open-loop or closed-loop depending on if sensor feedback is used to make control decisions. For example, a timer-controlled humidity management system is an open-loop system. The system triggers dehumidification at a pre-selected time for a pre-selected time period that is independent of the environmental conditions inside or outside a greenhouse or the crops being grown.
In contrast, a closed-loop system relies on sensor inputs to trigger control actions. For example, a closed-loop dehumidification system triggers heat-and-vent operations to remove humid greenhouse air only when a sensor senses the humidity is above a certain level. A closed-loop automated system generally performs better in a greenhouse environment where both environmental conditions and crop characteristics vary. The system’s performance is dependent on accurate and reliable data collection for timely and proper control actions.
For more information on how this technology can benefit your greenhouse operation please contact one of our greenhouse engineers here.