Small System Hydroponic Growing Media

In hydroponic growing systems, the plants receive all their needed nutrients form the water and the air. NFT (Nutrient Transmission Technique) systems work on the principle of continuously circulating the nutrient rich water in the system, making all the nutrients available all the time to the roots that are immersed in the slow stream. The root picks up what they need when they need it directly from the water.

So, what is the function of the planting/seeding media?

Mainly, the media is used as a structural support for the root system, helping to stabilize the plant in its place. Also, the media should allow for easy passage of the water through it while letting some air reach the roots as well. There is no need for the media to supply any nutrients beyond what the water brings.

How do you choose the right media for you?

There are many considerations. Some considerations are practical, like cost, availability in your location, ease of use and durability or lifetime. Other considerations are functional, how they directly affect the growth of the plants, like stability, effect on the water and nutrients, aeration, and wicking effect. And there are health and environmental considerations like is the media biodegradable, does is pose a health risk when handling etc.

Sounds complicated? Don’t worry, it really isn’t that bad.
We have narrowed down the common types of growing media
and considered their advantages and disadvantages:

Coconut coir or Peat pellets

Also known as “Jiffy”, they are made from the ground outer husk of a coconut
or a compressed peat moss.

Advantages

Available in all hydroponic stores and most nurseries. Very easy to use

Place the pellet in the cassette and let it soak up water. These pellets have a great water absorption quality while providing good root aeration. place the seed in the center of the wet pellet and cover with some of the material you can scratch from the sides. The pellets can be reused for many crop cycles until they physically degrade and fall apart. They are biodegradable!

Disadvantages

The pellets are not inert and the do release nutrients, mainly potassium to the water. For advanced growers, it may change the ratio of nutrients you are trying to achieve. Also, some commercially available coir pellets are high in salt when the arrive. Although all medias are quite affordable, this may be the most expensive option.

Perlite

This is a puffed volcanic sand that can be purchased in bulk in various particle sizes.

Advantages

Surprisingly light weight and can be used for both seeding and transplanting. Provides excellent aeration to the roots and great wicking capabilities. Can be washed and reused indefinitely or thrown to the compost pile when the crop cycle is complete – enriching your compost with perlite! It may be the most cost-effective option.

Disadvantages

Handling dry perlite can produce fine dust that can irritate eyes and breathing ways. You can wet the perlite before handling or use protective mask and eye protection. Also, we recommend getting the largest particle size you can find to minimize the lose particles from floating around and eventually causing clogs.

Rockwool

Made from molten volcanic rock that is spun into thin fibers, that are woven into blocks.

Advantages

Easy to work with and widely available. Provides good water retention and root aeration. Can be used for seeds and seedlings and reused for many crop cycles.

Disadvantages

Rockwool may increase the PH of the water so you will need to keep a closer look on your PH meter and add acid more frequently to maintain the desired PH level. Rockwool is not biodegradable and is irritating to skin, eyes, and lungs. Better wear gloves, mask, and goggles when handling.

No growing media

Made from nothing and comes for free.

Advantages

You can’t beat this price! Just place your seedling in the growing cup, making sure the roots touch the bottom so they will reach the water flow.

Disadvantages

Can only be used with seedlings that are big enough to support themselves. Seeds will wash away with no structural support. If there is any issue with the water flow, like power outage, the plant doesn’t have much reserves.

Hard to choose? The good news is that you can use any of the above, mix and match or something completely different. While many other home systems come with pre-seeded expensive media, the Proleafy system is an open architecture. You can use the media that is available to you, and you are encouraged to experiment with other new and exciting solutions. Please share you experience our community!