Publications on Orchid Growing

Publications of the Society

Growing Orchids in Cool Climate Australia
The Bulletin (recent editions)

Selected Articles from the Bulletin

• Going Overseas and you want to bring back Orchids?
  
• Potting Mixes and Watering Regimes
  

Publications of The Society

Growing Orchids in Cool Climate Australia:
with Special Reference to Canberra

Written by members of the Society, this book covers topics such as What are Orchids, Structures for growing orchids, potting media, pests and diseases, Orchid nomenclature, Orchid Classification and of course how to grow many types of orchids in cool climate regions of Australia. An invaluable reference for novice growers and those with a passion for this delightful plant family. Published in April 2005, 128 pages with about 130 photos and illustrations. The book is available from the society at a cost of $20 plus $4.50 postage and handling. Payment by cheque or postal note only, payable to the Orchid Society of Canberra Inc and must accompany order. Discounts on orders of more than 10 copies. For further information, contact Robyn Noel 02 6258 5734. For address click here

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Recent Editions of the Bulletin

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Helpful Articles from the Bulletin

Going Overseas and you want to bring back Orchids? YOU CAN!!!

Non-commercial consignments of orchid tissue cultures are exempt from import permits. You are allowed to import up to six flasks of tissue cultures without paying for an import permit and a quarantine and inspection fee.

The following conditions apply to non-commercial consignments imported through our international airports:

• import permit not required
• person importing them must accompany the tissue cultures
• tissue cultures must be grown in an aseptic non-animal based medium in a closed rigid container that is transparent enough for its contents to be inspected and must have been grown only in that medium and container
• tissue cultures must be labelled with scientific names
• there are no restrictions on the number of plants that each container may contain
• there is no restriction on the size of the container

If the above requirements have been met the tissue cultures are inspected at the airport for any contamination. If no contamination is found the consignment is released.

For more information search the Australian Quarantine Inspection Service (AQIS) import conditions database at www.aqis.gov.au/icon

Author: Hans de Vries, Bulletin Vol 19 No 6 Nov-Dec 2004

Potting Mixes and Watering Regimes

At the March meeting we discussed potting mixes and watering regimes.

I thought I might add my penny's worth to the discussions.

The one thing about growing orchids is that it's difficult to be dogmatic. Everyone's collection is different. Some have large collections, some have small collections, some have a glasshouse, some grow in an area in their house, some grow terrestrials, and some grow epiphytes. Our individual circumstances are also different. So what suites me in terms of orchid culture isn't necessarily right for someone else. Epiphytic orchids can either be mounted, potted or some cases just hung up to grow on their own. I will limit myself to discussing potted orchids.

Most potting media is bark based. It is easy to use and until recently, fairly easy to obtain. Most importantly orchids generally like to grow in it. I have been growing orchids for nearly 30 years. I grow an eclectic collection of different genera that seem to grow well as a mixed collection. I grow Australian dendrobium species and their hybrids, cattleya, laelia and sophronitis species and mini-catt hybrids.

My glasshouse is 32' x 16' and is as full as it can get.

I have seen a number of potting mix fads come and go and I have tried a number of different types of mixes and additives. At one time I was told that dead bracken fern was good to add to the standard bark mix, so I spent weekends collecting it, cutting it up and mixing it in with the bark. It didn't make any difference and was too labour intensive. Charcoal is another additive which it is good but can be difficult to get. Some people use Styrofoam. I tried the beads which are available for use in bean bags. The problem with them is they stick to everything and you only have to get a breeze when you are potting and they go everywhere. The crunch came when my wife removed some of them from my then infant daughter's nostril. It was politely suggested that I get rid of them, which I obediently did!

So what do I use? I use treated pine bark mixed with pebbles for nearly all my plants. The pebbles and bark are mixed on the basis of 40%:60% by volume (or whatever looks right at the time). Some plants seem to like a higher percentage of pebbles, namely the rupicolous laelias. I use medium size bark for all plants except the larger pots of mature Dendrobium speciosum where I use a mix of medium and coarse grade bark with the medium size pebbles.

I do not wet the mix before use, but I do water the pot after potting to wash the dust out. Sometimes this doesn't happen until the collection is next watered. The pebbles can be bought from most landscape centres either in large plastic bags (approx $10) or more cheaply in a garbage bin ($1) or bucket (nothing, if you're a smooth talker). I use quartz pebbles or blue metal which I find equally as good (don't collect it from the side of the road!).

Why the pebbles? Firstly, and most importantly my plants grow well in a pebble and bark mix. It provides good drainage and doesn't break down too quickly. Secondly, bark is expensive and by mixing it with pebbles it goes further. I have been using this same basic mix for 20 or more years and it continues to serve me well. What failures have I had? There are 2 bark types that don't work well in my conditions. They are boiled bark and composted bark. I water erratically, sometimes once a fortnight at other times every day depending on work commitments and the weather. Boiled bark dries out too quickly and I can't get it to retain moisture once this happens. Composted bark just rots down when watered and turns to mush killing all the roots. The best bark I have ever used was Californian redwood bark. York Meredith in Sydney used to import it. Unfortunately it is no longer available.

Some plants I grow in sphagnum moss. This is generally restricted to mini-catt seedlings and any plants that are looking sick. The sphagnum is loosely packed in the pot and topped off with a layer of pebbles to stop slime growing. The mini-catts only stay in the sphagnum until they are growing well, when I move them into my standard mix. As mentioned above, I water erratically. However, when I do water I water heavily, that is until the water runs through the pot. Everything gets watered at the same time. I water with tank water Summer and Winter. None of this standing a bucket of water in the glasshouse to warm up - I don't have the time.

If plants are looking a bit desiccated (it is usually the pots of large Dendrobium speciosum) they are stood in a bucket of water overnight. The same goes for plants in sphagnum moss. The moss once dried out is hard to wet again, so they also get dropped into a bucket of water overnight. I will often drop mounted plants into a bucket of water for the night as well.

There is some good advice on potting mixes and orchid growing in general on the Down Under Natives Orchids web site at: http://www.duno.com.au/growingtips.htm.

Good growing.

Author: John Ryan, Supplementary note to Bulletin, Vol 20 No 3, May-June 2005.

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