Photo: FrostBoss C49 machine installation.
Frosts are climatic events that cause great concern in cherry production, due to the potential productive and economic losses that they can generate. If you do not yet have an adequate frost control system, now is the time to do so.
The first rainfall events have already been recorded in several regions of central Chile and weather forecasts indicate that they will be accompanied by frost, a condition that can seriously affect cherry orchards, especially during certain phenological stages of the plant. Therefore, it is extremely important to anticipate and define which frost control system will be used during the winter season.
Frost is a meteorological phenomenon where the ambient temperature drops to the freezing point of water, that is, below 0° Celsius, due to radiative cooling from the ground to the atmosphere, which generates a thermal inversion that reaches from 5 to 20 meters in height.
FrostBoss, a leading company in frost control, offers solutions in this regard, using large fans that are installed in production fields.
“What does the machine do? The axis of the machine is more or less 10 and a half meters high, so with the propellers it gives us a range between 8 to 13 meters high, and at that height the thermal inversion always presents a warmer air temperature (in radiative frosts), so we take the air and throw it towards where the crop is, then we manage to raise the temperature we have in the orchard,” explained Juan Pablo Calvo, General Manager of Sociedad Comercial Terra Verde, representative of Frost Boss in Chile.
These are high-tech New Zealand machines that have been present in Chile since 2018.
“We were the first to bring in multi-blade machines. We have machines with 3 to 5 blades. With this we have managed to considerably reduce noise and fuel consumption compared to our competition. For example, the FrostBoss C49 machines (4 blades) produce 10dB less at 300 meters than some 2-blade machines on the market… a difference of 10dB is perceived by the average listener as half the noise. This year we hope to have close to 300 machines, counting the previous ones, and next year we will reach 500 and thus increase year by year,” Calvo explained.
More blades with less diameter, running at a lower speed sounds simple enough, but there is another important factor in making the theory work, and that is the blade design. The distribution of diameter, twist and thickness determine the efficiency of the blade. FrostBoss propellers have been designed with a true constant pitch along each blade from tip to root. The result is that the wind momentum leaving the fan is more consistent, minimising any air turbulence and the resulting wind stream maintains integrity beyond the fan. Independent testing has shown that the result is superior thrust, less noise and improved fuel efficiency with better coverage.
It is intended for use in any crop prone to frost damage, including cherry trees, which represent the vast majority of crops in Chile that are already using this technology. A frost between the phenological stages of swollen bud and exposed branch can be lethal to fruit production.
“Previously, two-blade machines consumed around 35-40 liters of diesel per hour. We managed to reduce noise and fuel consumption, since by having more blades they work at lower revolutions, which translates into lower fuel consumption and noise. The performance of our 5-blade machine is 20 liters of diesel per hour, and the 4-blade machine, which is the most sold, 21 liters per hour, which practically translates to half the fuel consumption and this is extremely important today due to the current price of oil,” said the representative of FrostBoss in Chile.
The frost control fans use John Deere engines with mechanical injection, with 6 cylinders of 170 horsepower: “This is also important because it is an engine that has a spare part in Salfa, which is in practically all agricultural cities, so, in case of any type of maintenance, the issue of spare parts will not be an issue.” In addition, we have 24/7 after-sales service throughout Chile,” explained Juan Pablo Calvo.
An important point for this season is to purchase these systems in advance, due to the logistical problems that have been reported worldwide.
“Of the latest containers that have arrived, a large percentage has already been sold. The idea was to bring more machines, but sea freight is taking longer than expected. In the past, we could have a shorter response time if the client wanted to buy a machine shortly before the frost, so now the call is to anticipate purchases,” concluded Juan Pablo Calvo, General Manager of Sociedad Comercial Terra Verde, representative of FrostBoss in Chile.
