Newsletter of the

Species Orchid Society of

Western Australia (Inc)

Vol 32 No 11

April 2021

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Editor e-mail: - Ph/Fax: 9296 1765

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Members of Note
Quiet Achievers
&
Life Members

Members Orchid Collections

Members can have pictures of their orchid collection posted here. Just email Tony

Michael Zink's Orchids

Brassavola nodosa

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Orchid Articles

Paul Carver's
Angreaceum
sesquipedale

Download; Plant Display Template

Species Orchid Society Rules PDF

IMPORTANT INFORMATION

April General Meeting:-


The General Meetings will be conducted in accordance with State Government and City of Canning COVID-19 guidelines. If you have a temperature, fever, respiratory infection symptoms or are feeling unwell, please do not attend. Tea, coffee, juice and water will be provided.
Members are asked to assist in cleaning surfaces after the meeting. All tables, switches and door handles are to cleaned and disinfected, and we will also disinfect all chairs used. Hand sanitiser will be provided and members are asked to use it.
Please ensure your signature in the attendance book is legible. Visitors will be asked to provide their name and contact details.

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NEXT MEETING - Tuesday 13 April 2021@ 7.45
AT WILSON COMMUNITY HALL
,
Braibrise Rd, WILSON

Catch up with us on Facebook!!

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Anne O'Callaghan Cultural Award:


Awarded to Peter for Aerangis articulata.

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MINUTES OF THE GENERAL MEETING
19 March 2021 7.45pm
Present: 30 members as per register.
Apologies: 6 as per register.
Visitors: Jenni ,
New members: Nil
Minutes: Acceptance of minutes from
December meeting moved Arnold, seconded Graham. Carried
Business Arising: Nil

Raffle: Lynne, Chris, Graham, Arnold
Badge Prize: Bruce

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Ian's Orchid

Bulbophyllum emiliorum

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General Business:

1. Peter reminded members that annual membership payment now due and that there are committee positions vacant. Members encouraged to give some thought to standing for committee.

2. Peter advised members of the SEOS invitation to participate in 2021 ISODW. The venue is Kelmscott Hall, 60 River Road Kelmscott WA 6111. Set up and judging Friday 6th August 2021, open to public Saturday 7th and Sunday 8th August 2021.

3. He also advised that the Spring Orchid Fair is to be staged at Aranmore College, Leederville. This event will be open to public Saturday and Sunday 21-22 August 2021. Possible set up on Friday 20 August.

4. He advised of invitation from WJOS and NDOS to participate in the Northern Orchid and Garden Fair at John Septimus Roe College, Mirrabooka. 3-4 July and 9-10 October 2021

5. Show of hands indicated that members wished to participate in these events, accepting requirement to support displays and assist during events.

6. Ken advised that Kevin Butler, Ezi-Gro Orchids has allowed the society to take part in a flask import from Ching Hua Orchids Taiwan. We have ordered 2 flasks of:
Brassavola cucullata 'Ching Hua' x self
Dendrobium anosmum
var. huttonii coerulea
Dendrobium cucumerinum
Guarianthe aurantiaca
Mishima Spot sib
Guarianthe bowringiana coerulea
x self
Jumellea confusa
Oerstedella wallisii
Oncidium stacyi

Trichocentrum splendidum aureum
Flask cost is A$1,000 plus estimated $250 towards import costs.
Purchase of flasks is being undertaken to provide future monthly plants as it is becoming impossible to source 20-25 seedlings in Australia for club monthly plants. Members will be asked to help us grow these plants once they have been deflasked. Committee has also approved proposed purchase of further 20 raffle plants from NSW for $500 plus $150 permit, postage and inspection fees

7. Life member, Noel advised that he was no longer able look after his orchids and wishes to sell his collection. We have purchased 75 species orchids for raffle prizes. We may need assistance to help grow some orchids until we need them.

8. Committee recommends that Tom & Pat be awarded honorary membership in recognition of their many years of
support for the Society; Pat as our auditor and Tom as our auctioneer. Decision was applauded by members.

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Ken & Chris's Orchids


Anacheilium radiata


Cattleya elongata


Dendrobium spp
aff crocatum


Dendrochilum latifolium
var. macranthum


Dendrochilum spp


Laelia fourneiri


Macroclinium bicolor


Phalaenopsis fasciata

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Financial Report: Treasurer's report was presented by Treasurer Adrian. Account
balance $8,970.52. Acceptance moved Ian, seconded Jane. Carried

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Adrian & Dee's Ochids


Cadetia taylori


Dendrobium rigida


Coelogyne tomentosa


Maxillaria meleagris


Stanhopea inodora

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FORTH-COMING EVENTS

Home visits:
At 10 am on the Sunday after the fourth Thursday of each month. Please bring chairs and food to share.


2 May 2021 Peter, Armadale
30 May 2021 John, Bicton.

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WOC 2024 Perth Update

Bruce was invited to update members on Perth's WOC for 2024. Bruce advised that the Taiwan WOC scheduled for March 2020 was postponed until 2021, and has now been planned as a virtual event for late April 2021. A short e-mail advice from the WOC Trust President, Liz Johnson confirmed that Taiwan will host the next WOC in 2024, and applications will be invited to host the event in 2027.
All references to Perth's successful bid to host the WOC for 2023 have been removed from the WOC Trust website. This action has occurred without any prior consultation with the Perth WOC Organising Committee despite our efforts to communicate with the Trust. In our view, this behaviour demonstrates the Trustee's lack of professionalism, absence of transparency and integrity and maintains the Trust's position of early 2020 when the President communicated with us strongly suggesting that Perth withdraw is hosting application.
At that time we responded that we would not do so, and sought an explanation for the Trust's decision, and information on the process to enable us to appeal this unreasonable request. We have not received any response from the President or the other Trustees to this request.
A draft response has been prepared to be sent to the Trust about their unjust decision to strip WA of the hosting rights that we legitimately won in 2017, and questioning their lack of business acumen. This response will be widely distributed to Australian and international orchid organisations to ensure that the facts are known.
It is therefore planned to stage a major national orchid event in 2023 with an international flavour to provide an opportunity for state, national and international orchid enthusiasts to gather in WA and be exposed to our unique orchid flora and generous and friendly hospitality.

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Peter's Orchids


Aerangis articulata


Brassavola nodosa
Dawsonii


Cattleya intermedia alba


Dendrochilum latifolium
var. macranthum


Gongora pleiochroma

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NOTES FROM YOUR COMMITTEE
1. At the April General Meeting, three large specimen orchids from Chris's collection, Angraecum eburneum var. giryamae (in spike), Eulophia petersii and Cattleya purpurata roxo-violeta will be auctioned. As advised last meeting, we have agreed to purchase Chris' collection to be divided, repotted and used for raffles.

2. We have 10 each of two Dendrobium species as monthly plants for April. They will be numbered and you will be able to buy the species that carries the number you select. If there are unsold plants at the end, you will be able to purchase a second plant.


3. The next general meeting of Orchids Western Australia Inc. will be held on 18 April. Matters on the agenda include:
(a) Proposal to stage an international orchid event to be staged in Perth in late August 2023;
(b) The level of financial support for ISODW to be staged by SEOS in early August 2021.

4. The Society's Annual General Meeting will be held in conjunction with the May general meeting. We currently have vacant committee positions - if you are interested in joining the management committee, please speak to one of the current committee members. It is important for the well-being and growth of our society that we have renewal in both our general and committee membership

5. The Society's financial year ends 28 February 2021 and annual membership will be due. Given the current management of COVID-19 in WA, it is most likely that the AGM will be held at the usual time in May.
Some ordinary committee member positions are presently vacant and we encourage members to consider nominating for these vacancies. Remember that you need to be financial to nominate and to vote at the AGM.
Payment can be made to the Treasurer at a general meeting, by cheque sent to the secretary or by EFT to the Species Orchid Society of WA account at Bendigo Bank, BSB 633-000, Account number 122491988. Please include your surname in the transfer.

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Tony & Mavis's Orchids


Phalaenopsis deliciosa


Phalaenopsis deliciosa var. hookeriana


Phalaenopsis pulchra

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Correspondence:
Inwards:
1. E-mails - South Eastern Orchid Society - ISODW 2021 invitation, Wanneroo/Joondalup invitation to participate in Northern Orchid and Garden Fair
2. E-mail - Orchids WA postponed meeting agenda
3. E-mail - City of Canning change of hall booking from 7th to 14th December 2021


Outwards:
1. E-mail - City of Canning re COVID-19 contact register sheet January GM
2. E-mail - Ezi-Gro orchids confirming flask order from Taiwan
Acceptance of correspondence report moved Ray, seconded Charly. Carried

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A message from The Water Corporation

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The difference between

Phalaenopsis amabilis & Phal. aphrodite subsp. formosana

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WA terrestrial orchids in situ – a four-day field trip to the Mid-west

http://members.iinet.net.au/~emntee/Orchids_in_The_Mid-west.htm

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If you haven't ordered your new badge yet, please see Mich. The cost for badges with a magnetic clip is $13.50, and with pin is $11.50.

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Unusual and Surprising Orchids and their
Reproductive Biology
by Ken Jones

Cont. next month

See the whole article HERE

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FOR SALE/WANTED

Harry would like to purchase the following.
Brassavola cucculata
Dendrobium torresae

If you have spare plants/divisions for sale, please contact Harry on 0412 403 696 or by e-mail to harry.ashton@live.com.au

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MONTHLY PLANT

Dendrobium aduncum
Dendrobium clavator


Cost: $5.00


Country of origin: South East Asia

Dendrobium aduncum

Photo source:

This month's plants (10 of each) were donated by our Qld member Eric Beltrame.
Dendrobium aduncum Lindl. 1842 Section Breviflores comes from mainland and island South East Asia where it is epiphytic in subtropical forests and broadleaf, evergreen lowland forests and primary montane forests near rivers at 300-1300m as a medium sized, hot to cool growing species.

 

 

 

 

 

 

 

 

 

Source:
Dendrobium clavator Ridl. 1896 Section Crumenata is a terete-leaved species from wet lowland forest in peninsular Malaysia as a small sized, hot to warm growing epiphyte. Over time, this species forms large dense clumps.
Both species can be grown in pot culture, or if you can maintain high humidity through the hot dry summer, on slab mounts as this more closely replicates their natural environment, and better accommodates the growth and flowering habit. Both species require a drier rest period in winter where the plants are allowed to dry out between waterings.


Unfortunately, many Dendrobium species seem attractive to two-spotted mite (aka red spider mite), and mealy bug, so care should be taken to ensure that the plants are grown where there is good air movement, and that remediation is initiated promptly if the tell-tale signs of 'silvering' on the leaf underside is visible as red-spotted mite reproduces very rapidly. Wettable sulphur will control the adults, but for heavier infestation that includes eggs and nymphs, a miticide such as Stealth®, Acramite®, Floramite ® or Vertimec® is required to control this destructive pest

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Fresh air movement is essential for healthy plant growth
(reprinted from an article written for the Paphiopedilum Study Group)


Introduction
We all know that successful orchid culture requires many ingredients. While discussions often centre on light, humidity, heating/cooling of orchids, nutrition and media, one of the most important factors to which we need to pay attention to for plant health, flowering and general wellbeing is air movement. Air movement includes the movement of a constant supply of fresh air to both the plant leaves, and to a lesser extent, to the roots through open and well drained media.


As with all of our discussion topics, this topic will inevitably involve some "do as I say, not as I do" moments for all of us. One of the most significant challenges is that we all try to keep too many orchids from too many different genera in our limited glasshouse or shadehouse space. This inevitably means that the plants are too close together, often with leaves touching one another. What this does is allow insect pests and fungal, bacterial and viral pathogens to transfer from plant to plant, while restricting the free flow of fresh air that the orchids need. Simply providing more space between plants is probably the most significant thing that we can do to improve the wellbeing of our orchid collection, but is often difficult given other constraints. Trevor grows his plants in 8 pot trays used by commercial nurseries that ensure that there is an air gap between individual plants. All that is then required is to provide the required air movement.


What do we mean by fresh air and why does it matter?


The words "fresh air" in the context of a discussion about air movement are critical. When we think back to the times when orchids were collected from the new world in the 18th and 19th centuries and transported back to Europe, most were condemned to a slow death in crudely heated glasshouses designed to replicate what were then believed to be the hot, wet tropical conditions of their natural habitat. Given what we now know, even the very best growers of those times got it wrong. The fact that any orchids survived this treatment is testament to the resilience of this group of flowering plants. During the cold winter months in Europe, glasshouses were closed up, heated with wood stoves and the ingress of fresh, but cold air excluded in order to retain heat. History reveals that many, many thousands of plants perished as a result. The key message for us is that fresh, moving air is essential for orchid health throughout the year.


In the 21st century, we have made great advances in replicating our orchids' natural environment. As hobbyist growers, the cost of sophisticated technology is often prohibitive, but automated humidification, air quality management, air movement, temperature, nutrient, water and light intensity and duration are all available to growers who have the money to invest. While systems manufactured in China are reasonably priced, it should be noted that they appear to lack reliability when compared with similar but considerably more expensive products sourced locally or from Europe or the USA.
The challenge for all of us therefore is how to get the best result for the least expenditure, make the best use of available space and aspect/location constraints, and to grow our plants well. Paying attention to these aspects of orchid culture will help us design and construct growing areas that provide environments in which our plants can thrive.
As a group, we meet at one-another's homes, which of itself presents opportunities to learn from others. There are almost always things we can do, and changes we can make that will help improve our orchid growing environment, although for many of us, the constraints such as lack of room to expand our glasshouse or shadehouse, or overhanging trees are actual barriers.


Where do our orchids live naturally?
So how does this topic about air movement specifically apply to some of the orchids that members of the Paphiopedilum Study Group might wish to grow? These genera are by and large, tropical or subtropical evergreen terrestrials, lithophytes or epiphytes. We principally grow them in pots in an open bark or similar media, in hothouses or shadehouses following hydroponic principles for their culture.


As Tony Bud demonstrated in his discussion paper on Calcicolous orchids, the way that we grow them is not how they live in their natural habitat! Those of us that have been fortunate enough to see Paphiopedilum species growing in the wild will have noticed several things. One of the most important is the constant air movement that exists in primary and secondary tropical forests. This has both a cooling effect on us, and on the plants growing there. Often, the species in these genera are found growing on cliffs where they receive constant, moving fresh air or in well-drained leaf litter over limestone or occasionally on trees as an epiphyte. Even in hot, steamy, lowland tropical and sub-tropical rainforests where these orchids are found, plant leaves, whether in the canopy, lower story or orchids, ferns and other flowering plants are constantly moving, both day and night. This air movement serves many useful purposes including keeping air temperature uniform by eliminating hot or cold areas.


Can we replicate our orchids' natural environment?
Space limitations faced by orchid growers living in suburbia dictate that we generally grow our orchids in small, rather confined growing spaces, and most often, as part of a mixed collection. Glasshouse/shadehouse design and layout is always subject to cost and space constraints. However, good planning, glasshouse/shadehouse siting that maximises light and radiant heat during winter can help overcome these barriers.
In the southern hemisphere, we want to maximise sunlight in winter, and for this reason, the optimum design is to have the longest dimension facing north, and unobstructed by trees or other buildings that reduce the photoperiod or day-length. The sun provides full-spectrum light and radiant heat which in winter (when the sun's path has tracked to the north) is essential for plant health. Similarly, in the southern hemisphere, the least useful light comes from the south, and accordingly transparent material can be replaced with non-translucent, insulating material (that could be a fence or house wall) without detrimental effect. Additional summer shading can be removed during winter. Generally, as we have now discovered, Paphiopedilum orchids require more shading in summer to reduce light intensity than most of the other genera we grow.


So, it is clear that a well-designed and sited shadehouse can help overcome air movement issues by encouraging airflow through the shadecloth, particularly from the south west and west, while it might be desirable to limit airflow from the east as this is the source of hot summer winds. Our hothouses do not afford us this luxury unless the impervious wall material is totally removable for summer. That said, during winter, we want to capture and retain as much heat as possible. Therefore, growing orchids in an impervious-walled hothouse means that we need to find ways to replicate the movement of fresh air that they would have enjoyed in their natural habitat.
In their natural habitat, the survival of orchids and many flowering plants is very dependent on continual, gentle breezes through the leafy canopy and lower stories of the rain forest. This air movement helps evaporate stagnant water trapped in leaf axils from periods of rain that would otherwise allow fungal and bacterial pathogens to breed. In the absence of fresh circulating air, orchids will die from these pathogens and will also suffer from a lack of readily available carbon dioxide that is circulated by the air movement. Effective ventilation also helps orchids tolerate intense light without leaf burn. While we seldom think about it, the distribution of carbon dioxide from plant respiration is an important factor to remember in this complex set of environmental factors, making air movement at night just as important as air movement during the day.
Moving air helps maintain leaf temperatures at desirable levels. Some plants, including orchids close the stomates on their leaves that allow transpiration of air and water from their leaves during the day, and leaves can overheat and be damaged without adequate air movement to cool them. Consistent and even air movement avoids stratification of cool moist air below the growing area and warm dry air above, where "dead spots" are minimised and damp stagnant areas, the breeding place for disease, are eliminated. In Western Australia where much of our summer is hot and dry with low relative humidity, too much air movement can reduce humidity and retard growth as the orchids are unable to take up enough moisture to offset that lost through the leaves resulting in desiccation and destruction of leaf tissue. In these instances, the supply of additional humidity is essential.


The challenge for us then is to replicate, insofar as it is possible, the natural habitat of orchids in our often cramped glasshouses. A graphic demonstration of the way that nature works occurred during the very hot days in January 2016 where some epiphytic orchids we have growing on trees in our garden were relatively unaffected by the heat with only minimal leaf burn. One of these orchids, Cattleya aurantiaca was in flower at the time. By comparison, several Stanhopea species hanging just under the roof of our shadehouse (under Solaweave) though being watered every day and misted up to 8 times a day were severely affected with the leaves badly burnt. Comparing the temperature and humidity in the leaf canopy of the trees in our garden to which orchids are attached showed a significant difference from the ambient temperature and humidity. I attribute this to the trees modifying the temperature and humidity in their immediate environment through transpiration, combined with natural air movement in the immediate vicinity.
The most obvious solution is fans; overhead, fixed or oscillating. Remember though that more air movement is not always better - hurricane-force winds are not beneficial air movement. The desired standard is gentle but consistent. As a simple rule of thumb, if the leaves of a hard-leaved orchid such as a Cattleya are moving about, you probably have more air movement than you need. The intensity of required air movement is directly related to humidity - the higher the humidity, the stronger the air movement needs to be (especially in winter where the ambient humidity makes it more difficult to evaporate any moisture on plants leaves before nightfall). Conversely, where natural humidity is low, any artificially generated air movement will serve to reduce humidity and lower the humidity around the plants. As previously explained, this can prevent roots being able take up enough moisture to balance that which is lost through transpiration potentially leading to plant mortality.


Oscillating fans such as those available from hardware stores at very reasonable prices are adequate, but need to be protected from moisture. While these cheap fans do not last long (perhaps 12-18 months before the oscillating mechanism fails), the cost is low and they are not overly expensive to operate, but their efficiency diminishes quite rapidly with the way in which we operate them. They need to be on 24 hours a day, seven days a week, i.e. day and night, all year round. It is worth paying more and buying fans with a higher output as they will do a better job of distributing fresh air to all points in the growing area.
Overhead (ceiling) fans are effective in moving large volumes of air, but can leave 'dead' areas that do not get as much air movement, or areas with excessive air movement that dry out the plants immediately below the fan, but leave others beyond this zone without enough fresh air. Generally, ceiling fans need to be operated at lower speeds to avoid these problems. Fixed direction fans, unless moving air through a distribution mechanism such as a poly sock can tend to dry out the plants in their direct path unless sited over or under the plants. We have a plate fan and poly sock in our glasshouse that provides reasonable air movement throughout the glasshouse, and the air is sourced from outside so is always fresh. However, fans designed for constant operation are expensive to purchase and replace.


Horizontal air movement is different and more beneficial than air movement provided by overhead fans that tends to be downwards and circular. Horizontal air movement is parallel to the ground driven by a series of fans that combine to move all the air in the closed space around in a coherent pattern. It is efficient as once the air is moving, it only requires a few well-placed small fans to overcome turbulence and friction to keep the air moving. Advantages, are reported to be better air mixing, elimination of hot/cold spots and disease control. However, my research indicates that this technology seems better suited to large greenhouses, for example 30m x10m rather than the small hothouses in which we grow our orchids as it is recommended that the fans are switched off when vents are open.

 


Fresh air can be introduced to the hothouse through ground level vents, making use of natural convection by allowing the air inside the glasshouse to heat up and exit via vents at the highest point of the glasshouse. While this can be detrimental to maintaining the high humidity that we want to preserve in summer, the constant supply of fresh air should be the principal objective and we can address humidity concerns by other means. There may also be some benefit in running piping underground to introduce fresh air as in our extreme summer heat, if the piping is buried well below the surface of the soil, some
significant cooling can be achieved as shown in the following
diagram.

 


Installation of a wet wall at one end of the hothouse and a large exhaust fan at the other end provides cooling, humidity and fresh air movement. A wet wall uses evaporation to cool and humidify air being sucked into the hothouse. These systems are often used in large scale commercial hothouses (see http://www.argosee.com.au/products/ventilation-cooling-heating/649/), but require all vents to be closed to operate effectively. Kevin Butler uses these wet-wall systems to cool and humidify his glasshouse spaces at Ezi Gro Orchids.
Another option is to run an exhaust fan, again close to ground level so that it blows fresh air into the glasshouse and another in the roof that exhausts the hot air (for maximum result, use exhaust fans that do not have to overcome louvres on the air entry/exit side of the fan as these can result in up to 20% reduction in efficiency). While these fans are not always economical to run, they are now available powered by photovoltaic cells, that will not be affected by power failures. My research indicates that these systems are relatively inexpensive (less than $100 on e-Bay) but I did not find much information about their efficiency and volume of air discharged. Wind-powered extractor fans (whirly birds) are also readily available from hardware stores and while requiring some wind movement to be effective, are obviously unaffected by power failures .
to be continued in May

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The Genus Phaius

See the article HERE

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Fiona Stanley Hospital Site Terrestrial Orchids

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Hygienic Practice

The benefits of hygienic practice in keeping your collection free of plant diseases.

Hygiene tips to keep your orchids disease free.

Checklist in WORD in PDF

See the full article HERE

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STANHOPEAS by Bill Mather & Ken Jones

See the whole article HERE

As usual, any and all comments are welcome

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