Plan your substrate project with care

Planning a block of substrate requires careful planning to prevent costly errors at a later date. The first consideration should be to have a detailed survey of the piece of ground that the substrate area is to be constructed on together with its relationship to the pump house.

With modern RTK GPS systems providing laser precision, it is a relatively quick procedure to obtain a detailed topographic "picture" of the land in question which will provide essential information to plan the project. For more information on GPS surveys click here

The survey will provide the information for the following

Where to trench the irrigation main, together with accurate distances
How to design the irrigation blocks to ensure even flow
Choose the most appropriate dripper specification
DNL (dripper non leakage) plan stating exactly where these devices need to be positioned

Planning the system

Water source - is it suitable for substrate? Do you need to install a water treatment system?
Balanced pumps running in tandem providing backup in the event of pump failure
Primary filtration with auto flush
Strategic placement of secondary filters - do not let the drippers become the filters!
Injection rig and computer - do you have the capacity to get round all valves quickly enough during peak demands?
Bags on gutters - sit more level then wire - enables even moisture within the bag
Solid pots on legs for drain - stand upright - even moisture and feed distribution
Correct installation of the drippers
Correct installation of the DNL devices
Run-off station installation per block

On-going checks

Pressure pre and post filter
Pressure post feed injection point
Pressure at start and end of irrigation blocks
If moisture variation found conduct a catch can test
Are you getting drain down? If so are the DNL's in the correct position
Have you got your irrigation right - squeeze tests, Run-off, Agri-tech moisture probes
Have you determined the optimum irrigation shot length? New coir will require little and often, established plants in older coir have slower infiltration rate and can therefore withstand longer shots. NB It's important to match irrigation shot length to the substrate mix to ensure max spread of water and nutrient
On higher plant water demand days increase the irrigation frequency and possibly the shot length during the midday period when experiencing extreme temepratures with high ET weather
Are you measuring temperature and humidity - these parameters will influence plant water demand more than sunlight