Moss Vs Bark - on Phalaenopsis
I have been noticing a fair bit of criticism lately over growing Phalaenopsis in sphagnum moss – not just here in NZ but also on Facebook pages from overseas.
This has arisen predominantly out of the rise of imported Taiwanese Phalaenopsis. The Taiwanese grow in moss for two reasons that I can see – firstly, the cost of the potting medium, secondly, its moisture retention. Over many years of research and development within the industry, moss has been determined to be the most suitable product to grow the plants in considering the environment in which they grow best (warm, humid).
Because here in New Zealand we don’t always have the warmth that they love, we need to adapt our care if we can’t adapt the environment the plant grows in. If you can’t provide a bit of extra heat around the plants during our cooler months, you need to consider that the plants aren’t using up the nutrients and water we provide it – they aren’t transpiring as much. Simple solution – cut down the quantity and frequency of watering and feeding.
Whether you use moss or bark depends on your growing environment and how good you are at watering the correct amount.
How can you tell when you need to water?
In the bark mix you need to gauge for yourself how wet the mix is – a not too easy task.
In sphagnum moss, bury your finger into the centre of the pot. You can feel with your fingertip how wet it is. If there is moisture, leave it alone. If it is drying out, water it.
The frequency of your watering/feeding regime will decrease significantly. Good orchid growing is about observation – is the plant getting what it wants when it wants it, the right amount of water, food, air, light, temperature?
Sphagnum moss should be packed in loosely enough that the plant still can get air in around its roots but tightly enough that the plant will be stable in the pot. The tighter the moss is packed in, the longer it will take to dry out. Change it out for fresh moss every 2-3 years. Since we have been growing in moss, our plants have thrived. A number of plants that arrived in the country in July 2017 have grown 4 new mature leaves since arriving – 4 leaves in 12 months! You can imagine what effect that will have on the flowering – think multiple flower spikes, think fat spikes able to support impressive flower counts.
I agree that moss is not suitable for everyone but it certainly warrants a trial at the very least.