Canadian Orchid Congress

March 1991
Volume 3 - - Number 2

Editor: Annette Bagby

How to bloom Dendrobium aggregatum

by Doris Jensen

Some people, I hear, experience difficulty urging Den. aggregatum to bloom. This is a shame since it can be such a generously rewarding plant when it responds favourably and produces its beautiful sprays of yellow flowers. Completely by accident I discovered a procedure which results in blooming success every year and I would like to share it with you,

My plant is mounted on a bark slab which, beginning in mid to late October, I hang high in the greenhouse in a cool and bright spot. It remains in this position all winter long and receives no water except an occasional misting in error.

In late March or early April when day length is increasing and the suns rays are stronger, I place the plant on the bench in a well-lighted position. The next step is critical to success. The base of the slab on which the plant is mounted is placed in a container of water. Gradually the slab becomes saturated and usually sprouts mushrooms! The slab is never allowed to dry out and the plant is additionally watered and fertilized along with the other orchids. (This usually consists of biweekly watering and occasional application with half strength 30-10-10)

Within several weeks the shrivelled pseudobulbs begin to fill out. Usually by a month to six weeks the bloom spikes can be detected on the sides of the pseudobulbs. When the plant is in bloom, I hang it up where it can be enjoyed and wrap the back and sides of the slab with a piece of green plastic to try and retain as much moisture as possible. When blooming is over I return the slab to its water container and leave it there until it is time to hang the plant up for another winter rest period. By this time the new pseudobulbs produced after blooming will be mature.

Since it does not seem to be necessary to use any growth clues from the plant it may be possible to get this species to bloom out of season by manipulating light intensity, day length and moisture.


Our April 27 & 28 annual meeting in Calgary is imminent and I hope I will see many of you there. The purpose of the Congress is to provide a means for Canadian Orchid societies to work together and assist each other. The annual meeting is the opportunity to initiate new ideas and to enlarge on existing efforts. A new executive must also be elected. Please be sure your society sends a delegate to take part if at all possible. The show, the hospitality and the lectures will, I am sure, be first class and most enjoyable.

COC Dues

If you or your society paid dues at any time in 1990, you are in good standing until May 31st, 1991. Further dues are not required until after June 1 of this year at the rate that will be set at the annual meeting in Calgary. If you did not pay dues in 1990, please remit $1.00 per member in your society or $15.00 for an individual non-voting membership to Nancy Tozer, 153 Stillview, Pointe Claire, PQ , H9R 2Y1,

C.O.C. Award

Chuck Travis is ready to receive requests for the Canadian Orchid Congress award from C.O.C. member societies in good standinq (dues paid up) for use in their show. The award will be mailed to you free of charge in time for your show provided Chuck receives your request a month ahead of your show date. We ask that you do the following:

  1. Select an appropriate class for the award that will satisfy the objective of encouraging exhibition of orchid flowers and plants in artistic arrangements at your show.
  2. Specify that orchid flowers must predominate.
  3. Make the award on the recommendation of the personnel that you have appointed to judge the show.
  4. Report back to Chuck Travis on who and what the award was made to and when. A picture would be nice to be able to show at a future congress meeting.
  5. Return the award if you do not use it. Chuck's address is:
    Mr. C. Travis, 403 Sandmere Place, Oakville, ON., L6L 4G5.
    Phone: 416-827-3555

Species Survey

The Southern Ontario Orchid Society Conservation Committee has started a computerised listing of species in members collections. I would appreciate receiving listings of species in the collections of your members for incorporation in a C.O.C. inventory. If each society could arrange to canvas its own members for lists of their species and then send them alonq, the resulting inventory could become the basis for worthwhile conservation projects.

Peter Poot

Blind Lake Bog
Maitland Valley Conservation Authority

Starting with last year's Mother's Day SOOS Orchid show, the show committee, chaired by Brian Rowe and supported by the SOOS executive, decided to use the proceeds of the show to further conservation.

Since most native orchids are very particular as to soil texture, PH., moisture content, presence of suitable mycorrhizal fungi and available light, habitat conservation is the only practical and long term means to their survival.

Brian was fortunate to have the help of Charles Sauriol for investigating worthwhile projects. This culminated in the selection of the Maitland Valley Conservation Authority's acquisition of Blind Lake Bog as the choice for our support.

Blind Lake Bog is located north-east of Brussels, Ontario and south of the Bruce Peninsula. It contains ten different orchid species: Arethusa bulbosa, Cypripedium acaule, Epipactis helleborine, Listera australis, Platanthera blephariglottis, P. hookeri, P. hyperborea, P. lacera, Pogonia ophioglossoides and Telepogon tuberosus.

The bog has been bought with borrowed funds. The total cost of land and development is $56,000. Mr. Ken Westman, general manager of the Maitland Valley Conservation Authority was at the SOOS meeting to accept the $3,500 cheque presented to him by Brian Rowe, as our contribution to the retirement of the loan taken out to purchase the bog.

Show Dates for 1991

March 23-24 Orchid Society of the Royal Botanical Gardens, Burlington, Ont.

April 6-7 Orchid Society of Nova Scotia's Spring Show Nova Scotia Museum, 1747 Summer Street, Halifax.

April 13-14 Central Ontario Orchid Society, Hespler Community Centre, Cambridge, Ontario.

April 20-21 Regina Orchid Society Show, City Greenhouse, Regina, Saskatchewan.

April 26-28 Ottawa Orchid Society, R. A. Centre, 2451 Riverside Drive, Ottawa, Ont.

April 26-28 Foothills Orchid Society First National Show and the Fourth Canadian Orchid Congress, University of Calgary, Calgary.

May 11-12 Southern Ontario Orchid Society, Civic Garden Centre, Toronto,Ont.


PRESIDENT: Peter Poot General Delivery Goodwood, Ont.,LOC 1AO (416)640-5643
SECRETARY: Mary Helleiner 834 Marlborough Ave., Halifax, Nova Scotia, B3H 3G6
PAST-PRESIDENT: Wally Thomas 7250 Arbutus PI., West Vancouver, B.C. V7W 2L6
VICE-PRESIDENT: Ken Girard P.O. Box 3063 St. B Calgary, Alberta, T2M 4L6
TREASURER: Nancy Tozer 159 Stillview Pointe Claire, P.Q. H9R 2Y1
EDITOR: Annette Bagby 172 Donnelly Dr., Mississauga, Ont. L5G 2M4 (416)274-6989 phone & fax

Canadian Orchid Congress Fees
Society Membership $1.00 per society member
Individual Membership $15.00

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