Greenhouse watering system is an important part of greenhouse maintenance. It keeps the plants growing healthy. Moreover, it helps you to save time and make greenhouse gardening easier.
How do you water a greenhouse?
Greenhouse is shield from the rains so you need to water the plants inside. Here are the ways to water a greenhouse:
- Watering by hand with a watering can. It is time consuming and is the most difficult out of the all ways to master. It is good to satisfy the needs of a particular plant, the second one saves a lot of time and helps to reach the pots at the back of the greenhouse.
- Installing a tap within the greenhouse and connecting a hose pipe. It will save you a lot of time. That way you can also reach the plants at the back of the greenhouse.
- Using sand (capillary) bench. This method has been around for many years but has never been very popular. You moist the sand with the watering can or a pipe which connects to the reservoir. Then place plastic pots into the moist sand.
- Using automatic watering systems. These systems work from the mainline directly via a tap or indirectly via the reservoir tank. The switching on and off is controlled by a timer or water computer with the sensors.
- Using semi-automatic watering systems. In comparison to the automatic systems, here you have to fill the reservoir tank manually. Also, you will have to switch them on or off.
Greenhouse watering system types:
- Sub irrigation Systems
- Drip/Trickle Irrigation
- Overhead Misters
- Sprinklers Method
- Perimeter Irrigation
How do automatic watering systems work?
The automatic systems work from the mainline either directly through a tap or indirectly through the reservoirs. These can be switched on and off manually but you can use a timer or a complex water computer.
A timer or a computer provide watering periods of different lengths on required days. Watering computer works when inserted in the compost sensors signal when irrigation is necessary.
How does sub irrigation work?
In contrast to the drip and misting irrigation where plants are watered from the above, in sub irrigation water is directed to the plants roots from below.
What are the types of sub irrigation?
- Capillary Matting
- Ebb and flow
- Trough System
- Flood Floors
Capillary Matting Greenhouse Watering System
How does a capillary mat work?
It is an improved version of the sand bench method. It uses the principle of osmosis. First, you need to place a polythene sheeting on the bench. Then, put a capillary mat on top of it.
Place the pots on the mat. Soil will absorb the water by osmosis and deliver it to the plant roots. Soil will continue to absorb water from the mat until it is evenly moist.
What is capillary matting made from?
The most common material for the capillary mat is thick cotton or polyester fabric. Both are highly absorbing. Mat should always be moist.
You can keep the mat permanently moist by using watering can or supply the water with drip lines.
As the top layer of the soil continues to loose water in the evaporation process, the moisture is absorbed from the mat. That way you can ensure that your plants don’t get over or under watered.
Ebb and Flow Greenhouse Watering System
Ebb and Flow also known as Ebb and Flood or a flood drain is a simplest hydroponics system. It is a method of growing plants without soil by using a nutrients rich water solution.
The basic principle of the Ebb and Flow system is that a tray with plants is filled with nutrient solution pumped out of the reservoir. The gravity returns water to the reservoir and it can be used again.
Trough Sub Irrigation System
Water flows through mounted on the bench or overhead of the greenhouse slightly sloping enclosures called troughs which contain pots.
Troughs are set up at slope from one end to other. “Spaghetti” tubing supplies nutrient solution goes to the high end and flows through the base of the pots.
The water leftovers collect in a cross gutter at the low end. Moreover, the nutrient solution returns to the reservoir and can be reused.
Flood Floors Sub Irrigation Method
In this method a sloped concrete floor is flooded and then drained. A whole greenhouse floor is laid with concrete and slopes toward openings in the floor.
Nutrients solution floods the floor through these openings and the excess water goes to the storage tank.
A good idea is to set up a bottom floor heating system. That creates optimal growing temperature and dries the floor after the excess solution drains to the reservoir. It stops the formation of algae and spread of fungal diseases.
Trickle or Drip Irrigation for greenhouse
How do drip irrigation systems work?
It is a micro irrigation system where water goes directly to the plants roots. Dripping system uses main feeder pipe which attaches to the header tank and small pipes wind from the main pipe.
Also, it utilizes nozzles which you need to install into each pot, tray or growing bed. You can lay the pipes on the soil level, throughout the greenhouse or hand them over the plant’s soil. That way water is released to each pot by gravity.
The system is automatic and uses timer which regulates the intervals when watering is needed. Also, you can control the amount of water your plants require for the optimal growth.
Moreover, you can use a computer and sensors in the soil to determine how dry the soil is. It can be set up to the watering needs of the individual plant.
Misting system for greenhouse
Similar to the sprinkler irrigation system, misting imitates a natural rain. Mister provides water to the plants in light mist.
Install the misters below the greenhouse roof approximately six feet above the ground. It can be easily automated with sensors which regulate the intervals between watering.
Is misting plants good?
Misting is great for raising a humidity in greenhouse and it also provides a cooling effect. Misting prevents infections with spider mites as these live in the dry air.
It is a good way to water plants of the same species in a large greenhouse. Misting practically distributes the same amount of moisture to each pot.
What is sprinkler irrigation system?
Sprinkler irrigation system is very similar to misting because it resembles the natural rainfall. Sprinklers spray water in the air and it breaks up into small water drops which fall onto the plants.
How do sprinkler irrigation systems work?
You can install sprinklers in the overhead pipework or secure in the ground on spikes. That way you can ensure a close range watering.
Automatic sprinkler controls the amount of water going into each zone. You can also choose a sprinkler with a different flow rate to meet all needs.
Greenhouse Perimeter Irrigation
Perimeter irrigation is when pipes are set up around the perimeter of a bench with plants so it creates an individual watering area. Pipes attach to a bench with nozzles at different intervals.
You can set up the nozzles at an angle of 45, 90 or 180 degrees so you can create a direction for water across the plants top.
You need to connect the pipes to the main tap, usually, the pipes of 19mm in diameter are used. Each nozzle sprays water directly into the middle of the bench to the plants roots.
