Micro-sprinkler Irrigation Technology for Greenhouse Structures

Micro-sprinkler irrigation is an irrigation technique that delivers pressurized water to the field and, through micro-sprinklers installed on the final-stage lateral pipes, moistens both the soil and the foliage of crops via a fine, low-flow spray. It is now widely used in greenhouse (plastic tunnel) floriculture and nursery cultivation, as well as for turfgrass and flowerbed irrigation, delivering significant water-saving and efficiency-enhancing benefits.

I. Materials and Methods

1. Selection of system equipment: Choose matching products that meet the technical specifications for micro-sprinkler irrigation.

2. Method: Use a submersible pump for pressurization and install micro-sprinklers on the greenhouse ceiling. The crops grown inside the greenhouse are flowers, such as chrysanthemums, Chinese roses, and roses.

II. Operating Procedures

1. Micro-sprinkler system

( 1) Pressurized water source: water pressure 2.0 ~ 3.0kg/cm² , optional head Flow rate of more than 20 meters per hour 5m³  With The submersible pump on top provides pressurized irrigation water that is free of sand, weeds, and debris.

( 2) Field First Section: Water Pressure Gauge 1 block, specification 1#/120 Screen filters, elbows, tees, and other connecting fittings.

( 3) Piping

① Supervisor: Select pipe diameter 40 ~ 50mm Pressure-resistant 3kg/cm² Anti-aging black PE semi-rigid pipe.

② Branch pipe: Select pipe diameter 16 ~ 25mm Pressure-resistant 1 ~ 2kg/cm² Anti-aging black PE hose.

( 4) Nozzle: Select one that is in 0.1 ~ 0.2MPa Under work pressure, traffic 40 ~ 60 L/h, Spray radius 1.2 ~ 1.5m of 360 °Atomizing nozzle.

( 5) Other accessories: various equal-diameter connectors, bypass straps, Teflon tape, end caps, and more.

2. System Installation

( 1) Construct a water storage tank: Build a tank with a capacity near the water source by the greenhouse (plastic tunnel). 6m³ The aforementioned semi-underground seepage-proof water storage tank 1 unit.

( 2) Micro-sprinkler Equipment Installation

① Based on the selected greenhouse (plastic tunnel) size and the spray radius of the micro-sprinklers, install the micro-sprinklers on the same side of the lateral pipe using a dedicated hole-punching tool. Arrange the sprinklers in each row in an isosceles triangular pattern.

② Install the branch pipes with spray nozzles horizontally as a suspended ceiling along the longitudinal direction of the greenhouse (plastic tunnel) in accordance with the design requirements.

③ Lay the main pipe along the width of the greenhouse and connect it to the branch pipes. Seal the end with a plug.

( 3) Assembly of the field head unit

According to the water pressure gauge The filters should be assembled in the specified sequence using the provided connecting fittings. Wrap oil-free Teflon tape around the threaded connections to prevent leaks. If conditions permit, a fertilizer injector can be installed between the pressure gauge and the filter.

(4) Connect the water pump, the field headworks, and the main water delivery pipeline.

3. Sprinkler Irrigation Water Supply

(1) Pre-stored sprinkler irrigation water: in advance 2 ~ 3 The tank is filled with well water, tap water, or clear river water for preheating.

(2) Water Supply: Start the water pump to supply water, while closely monitoring the water pressure gauge and ensuring that the micro-sprinklers are operating normally.

(3) Irrigation timing and water application rate: Develop a tailored irrigation schedule based on the crops grown in the greenhouse (plastic tunnel).

(4) Irrigation interval: Primarily determined by crop type, soil moisture conditions, and weather. At the same time, irrigation decisions are made by monitoring humidity and temperature inside the greenhouse (plastic tunnel). Generally, during transplanting, the soil’s relative water-holding capacity should reach 85 ~ 90% , remaining at in other periods 60% Left and right.

4. Fertilization

Base fertilizer is generally applied in a single, sufficient application as required; after topdressing, irrigation should be carried out immediately to prevent chemical fertilizer from damaging crop foliage. Foliar fertilization can be applied through irrigation, and pesticides can also be sprayed separately using a micro-sprinkler system.

5. System Management

1. Installation and management must be standardized; unauthorized disassembly or random drilling is prohibited.

2. Filtration equipment and water storage tanks shall be cleaned promptly to prevent sediment and debris from clogging or damaging the spray nozzles.

3. During crop rotation, store the sprinkler irrigation equipment properly to protect it from exposure to sunlight and rain, as well as from being disassembled or folded, thereby extending its service life.

III. Benefits

1. Water conservation: Micro-sprinkler irrigation delivers water evenly and uses less water than conventional surface irrigation. 50% ~ 70% , the quota is equivalent to surface irrigation. 17% , furrow irrigation 40% , with a remarkably high water-saving rate.

2. Labor-saving: With a micro-sprinkler irrigation system, watering can be accomplished simply by turning the water pump on or off, with no other operational steps required. The system also supports semi-automated fertilization and pesticide application, significantly reducing the labor intensity of field irrigation, fertilization, and pesticide application. Moreover, it eliminates the need for land leveling, thereby saving labor days.

3. Reduced pest and disease incidence, lower pesticide costs: Micro-sprinkler irrigation effectively and promptly regulates environmental humidity and temperature, thereby inhibiting the rate of pest and disease development, leading to a substantial reduction in their occurrence and a corresponding decrease in pesticide application.