Commercial Greenhouse Foggers and Sprayers: Applications that are Effective and Efficient
In the realm of environmental management in the commercial horticulture industry, foggers and sprayers are among the most efficient and effective in treating a grow area. Greenhouse application equipment comes in all sorts of varieties and complexity. From a spray bottle, hose, foggers, and even automatic/ robotic foggers, a greenhouse needs to have some form of fog or spray treatment. These treatments can be only water fog and mist to adjust temperature and humidity, pesticide applications, and other chemical applications and treatments. It should be noted that foggers and sprayers are different than ‘conventional
Hydraulic sprayer systems in order for a grower to be able to fully get the most out of a fogger and mist system.
Methods of Application
The most common way that a greenhouse administers and dilutes chemicals or other treatments is through water. This is in part to its ready availability, high surface tension, and will bead on crops especially on wax leaved varieties. There are two methods of spread that can increase the rate of contact and that is through mechanical and chemical spread. When speaking of misters and foggers, a spray drift is the most desirable as it will spread the water over a larger distance. Lateral air movement is important to achieve this as it encourages plant canopy penetration and can prevent droplets from merely sitting on a surface and staying put. Air should be considered the carrier instead of just water, as it is vital in achieving the correct spread as long as there are no gaps in circulation or too little air flow. Too much air flow will cause plants to become stunted due to possible wind injury or general stress.
Fogging and Misting Equipment
While greenhouse spraying equipment can be classified by the droplet size produced, it can also be classified based on the spray volume that it has. There are a few different fogging and misting classifications that are covered in the following sections based on volume. For specific questions for the fogger or spray that is specifically right for a greenhouse operation, a grower should reach out to an expert staff member at MORR Agriculture to receive recommendations and support in planning, installation, maintenance, and more.
High Volume (HV)
High pressure foggers and misters have applications that are performed at pressures that range from 500- 4,285 kPa or 75-700 psi. These systems have a flow rate between 3.9-5.7 liters per minute. With standard label rates, these foggers are able to dilute an application by broadcasting droplets that are larger than 100 microns. The overall goal of these systems is to achieve coverage over all plant surfaces without runoff. These sprayers and foggers are typically found as backpack sprayers, trailed sprayers, and boom sprayers. When using a manual sprayer system it is important to practice application and calibrate equipment before each application.
Targeted Low Volume (LV)
These foggers and misters have a much higher pressure rating than High Volume systems with pressures around 25,000 kpa or 3,000 psi. Flow rates approach 1L/min with this pressure range and can cover around 1,000’. With reduced rates over an area, droplets that form are between 25-100 microns. These spray applications are so fine that they do not result in actual wet foliage. This is beneficial to high humidity areas where excess moisture can be damaging. An example of this type of sprayer is an aerosol can.
Extra-Low Volume (ULV)
In extra low volume applications, flow rates are double that of targeted low volume sprayers and foggers with flow rates on average 2L/ minute that covers 10,000’. These droplets are very fine at less than 25 microns in diameter. Spray applications of fog with these sprayers do not affect the humidity and are great for short days of the year when nights are longer than the day. These sprayers are also used as a method of applying cleaners or other sanitizers to a growing area. When applying a mist with these foggers it is essential to close all HVAC system vents and fans. Some examples of ULV equipment are total release cans, thermal pulse foggers, and auto foggers.
Quick Tips for Fogger and Sprayer Use
It is recommended that operators use around 1: of carrier to 5L of spray mix, however, a higher proportion of care may be required for a more viscous or thicker product. The fogger should be run continuously during application even when moving between sections. A manual fogger should never be used as an automatic and left to run. When left to run the grower has the risk of a concentrated water application that can damage nearby plants. When fogging, a grower will need to apply between plants such as down alleys or walkways and between hanging plants. This is the ideal practice as it promotes the fog to expand and permeate into canopies for the best coverage.
Regular maintenance and care should be used on foggers and sprays intermittently, as well as some at the end of each application. Pressure should be released at the end of the application so that air does not stay in the equipment applying pressure and risking damage, HV, LV, and ULV equipment all require specific maintenance that is set to the manufacturer’s recommendation. Research should also be done to ensure proper handling and understanding of the sprayers and foggers.
For questions, suggestions, and product information be sure to contact a specialist at MORR Agriculture where experts are backed by decades of combined experience in the industry. MORR Agriculture understands that there are no cookie cutter operations and that each greenhouse requires a different approach. With services in planning, installation, maintenance, and more , as well as top industry products and equipment, MORR Agriculture is the ace up any growers sleeve.
About MORR Agriculture
Southern California based MORR Inc. is a vertically integrated distributor and service provider offering agriculture products, grow-facility services, and individually tailored solutions above and beyond what is currently available to the commercial grower.
Facilities across North America trust and rely upon MORR Inc. for massive inventories and immediate delivery of controlled environment agriculture equipment.
Call – 855-TRY-MORR
Commercial Agriculture 