Substrates used in Hydroponic systems

Substrates that can be used in simple Hydroponic systems

For people who generally live in rural areas, finding substrates like rice husk, or coconut peat is not a problem.


Rice Husk:

• is an excellent substrate which has one of the best drainage.
  
• since there is no compaction even after watering, it provides good aeration for the development of roots.
• The rice husk must be thoroughly washed in clean water as it might contain inert materials like sand, stones , insect eggs etc
• sun drying after washing is done for a period of 2 to 4 days.
  
• weed seeds sometime can get mixed along with the rice husk, so trials can be conducted to see if the rice husk substrate has any weed seeds in them. Soaking the husk in water & allowing to dry for a few days generally is the best method.
• In rice mills, burnt husk is also available. This is better as the chances of weed seeds, insect eggs etc are eliminated

Coconut peat
The numerous advantages of coconut peat can be seen in my early posts. Or you can view them again by clicking here

Washing the substrates:
before using either rice husk or coconut peat, they have to thoroughly rinsed in clean water


The most common problem found in coconut peat is it contains a lot of inert material, sand, soil & even insects. so it has to be washed several times , in clean water and sun dried for a couple of days before using it.

The photo below shows the residual sand/soil that i collected after washing 3 kg of coconut peat

This is mostly fine sand and soil particles, & this is detrimental to the dev. of roots. the presence of soil, results in compaction & formation of clay which will result in poor drainage, water logging & poor aeration. The coconut peat can also be filtered using fine filter net, before washing to remove the bigger particles

The heavier sand/soil particles can be found at the bottom of the container & the lighter coconut peat floats at the top.

the sun dried coconut peat can be used after 2 to 4 days.


Photos and content by Pritham 'Heavy metal farmer' denzil dsouza

Build your own germinating tray/tub for hydroponic cultivation

simple methods to start with your very won Hydroponic garden in your own backyard, roof top terrace or front porch

a simple plastic tray, preferably inexpensive, can be used as shown in the figure


next, a drain hole must be drilled into the plastic container. an electric drill can do the trick. even a piece of iron rod, heated to high temperature using a candle could do the trick of drilling a hole of desired size. the hole must be drilled at 1 inch from below the bottom of the tub as shown in the figure


a tank joint (15 mm dimension) must be used which acts as a drain tube, must be fixed as shown
the tub must be filled with suitable substrate. for this post, i have used rice husk. The rice husk has excellent drainage features & acts as a good substrate if one wishes to grow root vegetables.

Important Note
drainage is the key in any successful Hydroponic system. since most of the times, water which is rich in nutrients is added (fertigation) and so the water must not be allowed to go waste.
a little slope is also helpful in draining the trays of excess water, as it might start to rot the organic substrate and even the roots. fungal problems arise due to bad drainage.
the excess drained water is collected in collection containers suspended from the drain pipes as shown in the figure below.

once a week, clean water is added to the trays to 'flush out' the substrate of any harmful residues.

Photos and content by Pritham 'Heavy metal farmer' denzil dsouza