Basic Knowledge of Growing Phalaenopsis in Sphagnum Moss

In growing Phalaenopsis, sphagnum moss serves only to anchor the plant and retain moisture. When growing Phalaenopsis in sphagnum moss, opinions differ on whether the moss in the pot should be loose or firm.

If the moss is loose, the water content in the pot is higher, and the moss is more prone to rot and souring. If the moss is firm, the water content in the pot is lower, and the moss is less prone to souring and rotting. When a plant has just been repotted in fresh moss and starts growing, how firmly the moss is packed makes little difference to the plant. However, the metabolic waste produced by the plant every day is excreted through the roots. A potted plant differs from a plant growing in nature: a plant growing in a natural environment can break down the waste it excretes, whereas in an artificially potted plant, metabolic waste, fertilizer that cannot be absorbed and used, and residues of fungicides and insecticides all accumulate in the pot. After these things accumulate for a period of time, combined with moss that holds too much water, even the best moss will begin to rot.

Especially in the scorching heat of summer, this metabolic waste begins to ferment and the moss begins to rot, which consumes a large amount of oxygen in the pot and generates heat, making the temperature inside the pot higher than outside, along with some harmful nitrides and sulfides, and at the same time causing the pH inside the pot to change. This is also the biggest main cause of root rot in plants. Therefore, when the moss in the pot is packed firmly, the moss will not hold so much water, which can slow down the rate of fermentation and rotting. In addition, pouring a large amount of water into the pot provides enough water for plant growth, can also increase humidity, and can wash away harmful substances such as nitrides and sulfides. It can also lower the temperature inside the pot and, through this action, bring fresh air into the pot, reducing the chance of the plant dying from root rot.

The simplest way to judge how firm the moss in the pot should be is to pack the moss around the plant, insert it into the pot, and lift the plant with your hand; if the pot does not fall off, that is sufficient.