FIR OR REDWOOD BARK
Fir and redwood bark has been the most popular medium for orchids for many years. This type of bark is NOT the common "yard bark" you find in the garden shops which is mostly made from pine! Because the cost of potting bark gets higher every year, growers are looking for new less expensive mediums for their orchids.
Potting bark has been washed, sterilized, treated for weeds, and graded for size. The bark is available in three different grades: large, medium and small. The large size bark is good for large-rooted orchids such as Vanda
s and large Cattleya
The medium size bark is used for medium sized plants such as miniature Cattleya
s, and Phalaenopsis
The fine size bark can be used for your fine rooted orchids like the Oncidium
s and the ones that like to be moist like Paphiopedilum
s. Many people like to mix charcoal and perlite with the bark.
It is also a good idea to soak the bark for a day before you use it to help it absorb water and to remove any of the fine dust particles. Growing orchids in bark requires you to use a high nitrogen fertilizer such as 30-10-10.
If you live in an area where Sphagnum
moss grows, you are very lucky. If you are able to collect it live, it should survive in your orchid pots and your orchids will also like it.
Do not pack it in the pot, leave it loose around the roots. This type of moss is typically used as a base for mounting orchids onto pieces of wood, or other mounting material.
You can buy dried Sphagnum
moss in long fiber or short fiber types. I personally use the long fiber. New Zealand Sphagnum
moss has been used all over the world and is known to be about the best there is for orchids. Sphagnum
moss can hold up to 10 times its weight in water, so be careful with your watering and don't over water. If you tend to "overwater" don't use this media. Orchids that like to be moist do very well in this, such as Miltonia
s and Phalaenopsis
moss is also excellent to use on seedlings because it contains a natural antiseptic that helps stop "damping off" fungus disease.
Do not use the green dyed florist sheet moss. That is not Sphagnum
CAUTION: When handling Sphagnum moss you should always use gloves. Sphagnum
moss can contain a fungus that can effect some people. It is quite rare, but caution should be used when handling it.
is a heated natural mineral, and is often used as an additive in potting soil to help retain moisture and give an airy texture to the soil. It is also used to mix with many of the potting mediums for orchids. I use it with my bark, which helps hold a little more moisture. Some growers even use it alone with great success.
There are orchid lowers who grow their Phalaenopsis
in straight perlite
with great success. In that case uses 1/8" screened perlite.
Some of the advantages of perlite is it does not rot, therefore thrips or fungus gnats will not infest the medium. All epiphytes that can be grown in bark can be grown in perlite.
You can buy different grades of perlite from very fine to coarse
No, this is not the compressed, "briquette" type charcoal that you use in your barbecue.
Charcoal helps to keep the mediums sweet and keeps them from souring.
You can buy charcoal in large and fine grades
. The large grade is excellent to mix with the large or medium bark. It can also be used alone in the slotted baskets that some orchids are grown in such as Vandas. The fine charcoal is used in the peat mixes and the fine grade bark. It can be used with any of the media mixes.