Why use a mulch on your potted terrestrial orchids?

Here in South Australia, it is very common to see a covering of She Oak needles (Allocasuarina sp.) on pots of terrestrial orchids.  According to Les Nesbitt, NOSSA founding member and experienced terrestrial orchid grower, there are four reasons for this

  • It keeps the leaves up off the soil.
    • Provides good air circulation
    • Helps prevent leaf rot.
  • It provides nutrients to the fungi
    • This is very important for the fungi dependent orchids.
  • It stops pitting into the soil when it rains.
    • This is most likely to occur when pots are under the drip line of a shade-cloth.
    • Pitting exposes the root system.
  • It allows the leaves to readily come through because of its small diameters.
    • Other mulches, such as gum leaves, smother seedlings.

She Oak needles are the choice of mulch because it is

  • Long lasting and takes more than year to break down
    • which means that it lasts the whole growing season.
  • Does not become mushy or spongy
    • unlike pine needles and grass cuttings which breakdown more quickly into a wet soggy mass and contribute to leaf rot.

It should be noted that it is necessary to replace this mulch yearly.

These two pots were in the same area under the shadecloth.  Notice the damage to the pot without the mulch.

These two pots were in the same area under the shadecloth. Notice the rain damage to the pot without the mulch.

Advertisements

Leave a Comment

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s