How to Raise Plants in Semi-Hydroponics


Semi-hydroponic can create a high humidity environment for your plant's roots and prevent root rot. Have you tried it out?
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I love raising my orchids in semi-hydroponics. It takes the guesswork out of when to water plants. If you haven’t tried it before, I strongly encourage you to do it.

Semi-hydroponics is a method of growing plants that uses an inorganic medium instead of soil, bark, or peat moss. Instead, it utilizes an inorganic, inert, and solid growth media to support the plant and anchor the roots in place instead of genuine hydroponics, which uses a liquid solution as the growing medium.

How It Works

Semi-hydroponics, sometimes known as “passive hydroponics,” is distinguished from genuine hydroponics by using a wicking action of water rather than pumps. The wicking action of the medium pulls nutrients and water from a reservoir (typically a few inches of water at the bottom of the pot) up through the pot to the roots. This will supply the roots with a steady supply of nutrients and water.

This wicking action causes an environment of extremely high humidity at the plants’ root zone while also still allowing maximal aeration.

The most common mistake in plant care is overwatering, which causes root rot. But with a properly set-up semi-hydroponics system and functioning drainage holes, water will collect at the bottom of the pot only up to a certain point. This makes overwatering impossible.

Check out our DIY guide for information on how to create an ideal semi-hydroponic pot.

many hydroponic balls or roots

Mediums That Can Be Used

Semi-hydroponics can use a variety of growth media. However, they all have the same properties: They are inorganic and absorbent.

Usable media include:

  • LECA / clay balls 
  • Pumice
  • Loose gravel
  • River rock
  • Foam
  • Rockwool
  • Vermiculite
  • Perlite

The most common option from this list is LECA (Lightweight Explanded Clay Aggregate) balls.

Advantages

The following are some of the advantages of switching your plants to this type of growing method:

1. Less repotting

One significant advantage of soilless potting media is that, because they are inorganic, they reduce the frequency with which you must repot your plants. While organic media degrades over time, inorganic material does not.

The media can also be reused almost indefinitely. They only require a thorough washing and rinsing before they can be reused.

2. Reduced risk of root rot

Root rot is reduced by removing soil-borne organic bacteria and allowing the plant to consume the quantity of water it requires. When a plant is over-watered, soilless media don’t clump or get soggy like soil, allowing for increased aeration and healthy root development.

3. Fewer Pests

When a pest infests your traditional potting media, it can be difficult to deal with and identify the source of the issue. But with LECA and other inorganic media, you can easily see whether your media has bugs.
Second, most pests avoid semi-hydroponics media because it lacks the conditions for laying eggs and larvae that other mediums have. 

If you have trouble with fungus gnats, switching to this method is one solution to the problem.

4. Less cost over time

The cost of the LECA beads might be rather high at first. However, after you’ve completed the setup, you won’t have to pay any more money for a couple of years. There will be no need for constant repotting, which quickly adds up from a cost perspective.

mini syngonium plant in a small black pot

Disadvantages

1. Larger plants have the potential to tumble.

LECA balls are extremely light. They float to the top of the medium when watered. This might cause bigger plants to topple over if they are top-heavy to begin with.

2. Higher initial costs

LECA balls can be pricy. Even if they are reusable, the initial cost is substantial 

3. Accessibility of media

Soilless media are a little more difficult to come by than conventional soil. They cannot always be found at your local garden center, supermarket, or DIY store.

Watering Plants: The Reservoir Method

The reservoir method is the most frequently utilized method of watering plants (and the lowest maintenance).

This is accomplished by maintaining a reservoir of water below the potting media, where the water is wicked up through the porous potting medium to the plant’s roots.
The reservoir can be the bottom of the pot itself or it may be a separate container that the pot with drainage whole is sitting in. Whenever the reservoir gets low in water, simply add more water.

Flushing 

A thorough rinsing of the roots and substrate of the plant to remove mineral and contaminant buildup is necessary. This is not difficult to do. Simply put your plant into a sink and top-water it until the old water is flushed out of the pot and completely replaced with new water.

To sustain good plant development, this should be done regularly.

Fertilizing and Nutrients

How you fertilize your plants will depend on what type of plant you are growing. I often recommend diluting the fertilizer so that it is only half as potent. You don’t need to use a fertilizer that is specifically labeled for hydroponic growth. You can use any fertilizer that is dissolvable. 

When you get ready to water your plants, add some of the diluted fertilizer to the water. That’s it. You can do this every time to water your semi-hydroponically grown plants. You can also make a batch of this water to have in storage and use it on the fly as you need

Jeffrey Douglas
Jeffrey Douglas own a landscaping company and has been in the business for over 20 years. He loves all things related to lawns or gardens and believes that proper maintenance is the key to preventing problems in the first place.
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