By Eran Alon, Product manager – Dosing & Water systems
Netafim has recently joined forces in a unique greenhouse project for growing orange Ornithogalum dubium, also know as Sun Star, flower bulbs. This perennial which is part of the lily family grows to about a foot high with around 20 small cup shaped flowers in a variety of colours, and is native to South Africa, although now very popular the world over.
The project is being carried out in an 8,000m2 gable greenhouse in the centre of Israel, run by a team of father and his two agronomist sons. One of the sons initially laboratory developed the flower tissue culture which was then transferred to the greenhouse and planted in small trays.
During the first 14-21 days of growth, the plants are exposed to extremely humid conditions. They are currently in the midst of a five-month growth period, after which the “onion” bulbs will be dried and sold to exporters of the flower.
CoolNet ensures appropriate conditions throughout the growing period, and is installed at the height of the greenhouse gutter. It operates in six shifts (sections). CoolNet nozzles are placed in 3m x 3m positions, spraying mist at a flow rate of 22 l/hr.
The drip system features Netafim PCJ drippers – each of which has the angular inline Arrow dripper affixed – with a flow rate of 4 l/hr. The drippers spacing is 30cm. along 16 dripperlines for a total of 2,100 drippers operating at a valve total flow rate of 8.4 m3/hr. Launched following completion of the initial 14-21 day period, the system carries out irrigation and Nutrigation™ based on the plants specific needs.
To ensure that the greenhouse operates exactly according to plan, three additional systems were added.
CoolNet requires 5 bars of pressure to deliver pulses of mist whenever required. To ensure this pressure level, Netafim PBS (pressure boosting system) was installed.
The comprehensive plug-and-play system includes a pump, pressure sensor, expansion tank and electrical board that fit as a single, compact unit on an aluminum frame.
A temperature & humidity measuring device transmitting data to the NMC controller was installed. The grower decides the target temperature and humidity level at which CoolNet will spray mist at specific time intervals via the NMC. The fully automated system continuously preserves climatic conditions according to plants needs.
To carry out precise Nutrigation, Netafim FertiKit 3G Nutrigation system was installed. Controlled by the NMC, FertiKit 3G injects a combination of nutrients and water precisely balanced to meet the plants specific needs. At the same time, FertiKit also injects nutrients via a proportional or EC and pH control method based on the plants requirements.
FertiKit 3G also lowers the pH level of water from the main-line source from 6.9 to 5.7 before it enters the CoolNet water tank. The tank-filling process is fully automated thanks to a float switch installed in the tank. When the float switch recognizes that the tank water level is too low, it sends a signal to the system to start filling the tank. Once the tank is filled, the float switch sends a signal to the system to stop filling. The system also enables growers to choose different nutrient recipes for the drip system at each growing stage.
So far, the project is progressing extremely well and we believe it will prove to be a great success in the coming months.