Orchid enthusiasts all know that about that rumbling urge to create a new orchid potting mix!

Repotting is like refurbishing plant space for refreshing the growing medium from that store-bought plant, or it’s that time of the year again to take paying that extra attention to orchids in your care every, one or two years!

If that special orchid refreshing time has arrived, get ready for creating a homemade potting mix!

How do you know it’s time to re-pot?

  • The potting media might be decomposing or breaking down
  • There are sightings of overgrown roots
  • The plant has outgrown the container
  • Roots are starting to dilapidate with rotting or disease

If your orchid has reached any of these stages, it’s a calling for a new container or sterilizing the current one…. And also a change of the potting medium. Let us journey through potting mixture varieties at your disposal.

There are basically two options when getting the new potting mix ready. The first is getting a ready-made store-bought mix. The second way is the DIY choice. 

 It is obviously fairly easy walking into an orchid nursery or a gardening shop and tell them about your orchid variety and potting needs.

Then there is taking that soul journey to create your own potting medium bark mix that can really lift your budding gardening spirit and purpose-driven roots

 

Let us first round-up basics

The main purpose of potting media is satisfying seedling growth needs within container space that is fairly limited, and eventually transplanting into growing fields.

 A growing seedling supplies and stores nutrients, air and water to root systems. Effective media potting will result in healthy root systems and quality seedling that will survive when planted on the outside and commence with quick growth.

There are natural materials that are required for the healthy growth of roots. 

 

Biological Fundamentals of Assembling & Producing POTTING MEDIA 

Orchids differ from other plantations. They do not need soil! They need airflow and drainage. Now, this is when potting mixes come in. Let us take a look at what consists of good potting media. The key components are retaining moisture, rapid draining, good circulation and slow decomposition.

It is crucial to get the best potting medium for your orchids as this will determine the airflow to your plant and how often watering will be needed, and most of all directly affect the health of your plant!

Find the best potting media for your plant. No single combination works for the various orchids or growers. Experiment and identify what works for you and the plant. An incredible journey!

COMMON POTTING MATERIALS

Bark mix is a potting medium most preferred as it mimics natural growing environments of the epiphyte. It is possible to use bark mix for a wide variety of orchids including the beginners favourite, the Phalaenopsis or the Moth Orchid.

Common materials to compose bark mix include:

Fir Bark

There are three grades of fir bark:

  • Medium
  • Fine
  • Coarse

The finer bark can hold more moisture and dries at a slower pace. Coarse barks allow more air in and subsequently dries faster. It is fairly easy to get at a low cost.  It does, however, resist water and can decompose faster than others.

Tree Fern

Also available in grades, tree fern dries fast, is expensive and has a lower ability to retain moisture.

Sphagnum Moss

Sphagnum or peat moss is best for terrestrial mixes. It retains both water and air. It tends to retain a bit too much water though if it  is packed tightly or during decomposition

Perlite

Perlite resembles styrofoam. It is volcanic glass known as volcanic popcorn. It is porous which means it stores both moisture and nutrients and excess moisture is drained. It is non-toxic, free from disease, lightweight and inexpensive too. However, it can retain a bit too much water.

Coco husk chips

Coconut husk chips is a great absorbent medium that decomposes gradually. They do not drain as well as the coco bark or husk chunks 

Styrofoam peanuts

Most commonly used to line the bottom of pots, it provides aeration. If you are into green gardening avoid these as they do not decompose

Three Bark mix methods for Orchids

GENERAL

  • Aeration- Prepare your primary potting material 
  • Bark provides plants with airflow. There are various choices including Douglas Fir Bark, Ground Redwood bark or Osmuna tree fern fibre (to name a few.)
  • Moisture-retention – Prepare your secondary potting material 
  • The next step is the preparation of materials that help retain moisture when watering plants. Choose perlite, coconut husk chips or sphagnum moss.
  • Mix everything
  • Mix the primary and secondary potting materials at a  guiding ratio of  5:1. If you choose to use the  Osmunda tree fern fibre, soak it in water for at least  12 hours. Then combine it with the redwood bark at a ratio of  3:1

FINE MIX

The fine mix combo is recommended for orchids with smaller roots that like dampness like Miltonia’s, Oncidiums or Slipper Orchids

In a ratio of 4:1:1 mix the following:

  1. Fine fir bark, fine coco chips, redwood bark or fine-grade coco husk chips or redwood bark
  2. Fine charcoal
  3. Perlite

MEDIUM MIX

The medium mix combination is best for  Moth orchids, cattleyas, as well as a few mature orchids. The medium mix is great to choose if you are unsure what to choose for your plants. 

In a ratio of 4:1:1, create the following mixture:

  • Medium fir bark or coco husk chunks
  • Medium charcoal
  • Perlite 

Don’t worry about experimenting with ratios and materials as you will eventually discover the best pathway for your plants

Final notes to consider on the potting bark mix journey:

  • Terrestrial orchids usually grow in sphagnum moss. You can find Epiphytes growing on mossy limbs. Keep this in mind when it is time to choose materials.
  • Terrestrial orchids require a mix that is a much denser mix, like sphagnum and sand moss.
  • An important factor to consider is stability. Packing peanuts provide airflow but may be a bit too light for plants that are heavier 
  •  Texas A&M University  Botanists recommend 80% fir bark and 20% coarse sphagnum peat for  a Moth Orchid potting mix: 
  • University of Tennessee Horticulturists, recommend THIS 3 parts fir bark, 1 part perlite and 1 part chopped sphagnum moss for a Moth Orchid potting mix: