Substrate Planning

Proper Planning Prevents Poor Performance

Don't shortcut the planning process, time invested here will pay dividends in the future

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

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

Planning the system

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

On-going checks

  1. Pressure pre and post filter
  2. Pressure post feed injection point
  3. Pressure at start and end of irrigation blocks
  4. If moisture variation found conduct a catch can test
  5. Are you getting drain down? If so are the DNL's in the correct position
  6. Have you got your irrigation right - squeeze tests, Run-off, Agri-tech moisture probes 
  7. 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
  8. 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
  9. Are you measuring temperature and humidity - these parameters will influence plant water demand more than sunlight