How to Grow BIG Plants
plugs to eight-inch blocks . It ’ s a very effective medium but not environmentally friendly . Dry Rockwool or loose material can irritate skin and lungs , like fiberglass , and it ’ s not biodegradable .
Oasis Cubes is similar to Rockwool but made of biodegradable foam . It ’ s less irritating to the skin and eyes and only available in starter plug sizes .
Oasis Cubes
Peat Pellets are compressed peat that comes dried in a puck-like form . Upon watering , the peat expands for planting . Tight mesh netting holds the peat in place but allows roots to penetrate as they grow .
Root Riot Starter Plugs , a crossover between Oasis Cubes and Peat Pellets , are pre-moistened starter plugs made of pH-balanced sphagnum peat moss and formed to hold their structure without mesh netting as roots grow throughout and beyond the medium .
Pebbles , Stones , Rocks , and Gravel
Reduce , reuse , recycle — pretty much sums up this category . After harvest , this media can be rinsed and sanitized for the next round of plants . Seeds and clones will struggle to root if placed directly in the media , so it ’ s typical to start them in a cube , block , or plug and transplant them once roots protrude from the original media . While this style of media offers plant roots excellent access to air , it holds little-to-no nutrients and dries quickly , requiring constant watering . Before use , pebbles , stones , rocks , and gravel should be rinsed to remove dust and dirt . It ’ s suitable for use in the following systems :
● Nutrient Film Technique
● Deep Water Culture
● Ebb and Flow
Clay Pebbles are also referred to as Hydroton or Light Expanded Clay Aggregate ( LECA ). The semi-round balls with porous surfaces hold their shape and provide ample space for root growth .
Lava Rock is more porous than clay pebbles , providing more oxygen to roots . Heavier , it dries out more quickly , and inconsistently sized pieces can result in uneven moisture retention from one root area to another .
Growstones , a cross between clay pebbles and lava rock , is made from 100 % recycled glass bottles .
Rocks / Gravel are like lava rocks but can potentially impact the pH of your water or nutrient solution .
Fine Material
After a completed grow , this media can be recycled back into a soil mix or an outdoor garden . It can take plants all the way from seed to harvest , acting more like soil than the rest of its hydroponic media counterparts . Increased water and nutrient retention allow for less frequent watering sessions , but its application is limited to systems where it doesn ’ t have the potential to clog pumps or tubing . It is suitable for use in the following systems :
● Ebb and Flow
● Drip Irrigation
Coco Coir is ground coconut husk , available in loose or compressed brick form . Bricks are often cheaper due to reduced shipping costs and can be expanded with water to many times their compressed size . It may need to be pH “ buffered ” to avoid calcium and magnesium lockout if not already done by the manufacturer .
Sphagnum Peat is decaying moss with a consistency similar to loose coco coir . It breaks down over time and has an acidic pH that must be accounted for when watering with a nutrient solution .
Perlite , made of air-puffed , lightweight volcanic glass , has excellent water and oxygen retention .
Vermiculite is similar to perlite but formed from mica-like minerals and possesses greater water retention capacity .
Rice Hulls are the exterior shells that surround rice and are generally inexpensive as they are typically disposed of by rice producers . They allow for good oxygen flow and drainage but have limited water retention .
Sand — while technically a grow media , sand presents numerous challenges when used on its own and is only suitable for drip irrigation systems . Its tiny granules are sure to clog pumps and pipes .
Blends and Mixes
Any of these individual media can be mixed , formulating unique custom blends . Companies like FoxFarm have gone so far as to commercially offer pre-mixed products such as its Cultivation Nation 70 / 30 Coco Coir / Perlite media . These neutral media can also become the base for homemade potting soils by including nutrient-rich components such as compost , worm castings , and dry amendments , but that ’ s a discussion for next month ’ s edition !
A note on “ medialess ” grows : In many hydroponic systems , it ’ s possible to grow without any media . The only necessity is a piece of material to hold the plant ’ s stem in place while roots hang freely in the air or down into a nutrient solution . Reusable neoprene , foam , or silicone collars will all suffice in this style of grow .
Watch for Volume 2 in next month ’ s edition when we ’ ll explore soil blends .
For more information about YRG , visit www . year-roundgarden . com or call 816.216.6917 and be sure to tell them The EVOLUTION Magazine sent you .
Scan QR ► to see video about “ Types of Horticultural Lighting .”
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