Meets second Tuesday of the month at Rose City Park
United Methodist Church, 5830 N.E. Alameda
Editor: Mike Riordan (503) 256-0425
Editor: Mike Riordan (503)256-0425 Contacts: Teresa Bergman (360) 274-8292, Jeanette Benson (503) 649-4118
Next meeting Tuesday, November 10th, 2009 @ 7:30 p.m.
FLOWER OF THE YEAR NAMED
Resulting from a popular vote at the October meeting, Sorbet, B SC DB dark red/white, was named flower of
the year for 2010. Sorbet was originated by Cor Geerlings of the Netherlands . It is a tall, vigorous grower
as well as a good tuber producer. We anticipate having an adequate supply at our April tuber sale.
. MONTHLY CLUMP AUCTION
Our November meeting will feature a continuation of the “silent auction” of undivided clumps. If you have
extra stock you think other members might like, please bring the November meeting. This fundraiser
stimulated lots of interest and competitive bidding last month.
ANNUAL PHOTO CONTEST
Part of our program for November will be our annual photo competition. Photos may be either conventional
prints from film or prints of digital images. The competition will be divided into three categories: 1) Photos
of dahlia blooms, 2) Dahlia blooms with people or critters, and 3) Dahlias in landscapes or garden scenes.
There will be a ten dollar prize for each category and the best of all three categories will receive an additional
ten dollars. Please bring your photos in prior to the start of the meeting. There will be time for viewing and
judging during the refreshment break. The judges will announce the winners and award the prizes prior to the
conclusion of the meeting.
Cookie hosts for November are Phil Mingus, George Ermini and Tiffany Boatwright
PROGRAM FOR NOVEMBER
In addition to the clump silent auction and the photo contest we will have a discussion of what went well for us
in our dahlia gardens and what went not so well. New methods, procedures and stratagems will be honestly
evaluated. We hope to all be able to learn from one another, share our successes and hopefully limit our
disappointments. Which new introductions do you most want to grow or grow again next year? Which ones
from our Trial Garden would you most like to try?
Our annual board meeting will take place Saturday, January 16th, 2010 at 12 noon. We will meet in the
community room at the Georgetown Realty Office located at 1000 NE 122nd Avenue in Portland . From I-
205 North or South bound take exit 21A to Glisan Street . Take Glisan East (street numbers increase) to
122nd Avenue . Turn left from Glisan to 122nd. Georgetown is two blocks down 122nd on your right.
Parking is behind the building. We will start the meeting with a potluck luncheon. Everyone is encouraged to
bring a dish they believe others will find popular. All members are welcome at this meeting. You need not be
a member of the board to participate. We will be discussing what went well and where and how we can
improve. What do we want to change or revise in the show schedule to make it even better? How can we
increase participation in our annual show? How are we progressing and what additional steps need to be
taken to plan for our hosting the National Show in 2012? What changes would you like to see in our monthly
meeting programs? How can we go about attracting and retaining more new members? This is a planning
and strategizing session, so please bring your ideas and enthusiasm.
2010 DUES ARE SOON DUE
Why not take care of this now and get it out of the way? Judges please re me mber that you are required to
carry me mbership in both the A me rican Dahlia Society and the PNDC (Pacific Northwest Dahlia
Conference). PDS dues, ADS dues and PNDC dues should be combined and paid to the Treasurer as noted
below. Federation of Northwest Dahlia Growers dues are $10 and also payable through our Treasurer.
Mail to or pay at next meeting
Larry Sawyer, 11015 S.W. Berkshire, Portland , OR 97225
TRIAL GARDEN REPORT
Canby Trial Garden Director, Bill Mishler, indicated that the trial garden had a very good season. The
weather cooperated and there was ample supply of judges available to complete the task of judging the
seedlings. Of those hopefuls submitted, 16 out of a total of 31 passed. The highest average score of 89.15
was given to AC Rooster, a red stellar dahlia.
DIGGING IN 1946
In Oregon dahlias should be dug as soon as possible after the first killing frost. In any case do not leave in
the ground after December 1st and many growers plan to start digging by November 10th whether they have
been frost killed or not. There is one exception to this rule. If the soil is unusually well drained and the
tubers well covered with soil, one may risk leaving them in the ground all winter. If the spoil is heavy clay,
never take a chance as it always remains soggy enough to damage the tubers. There is always the added
risk of the weather being sufficiently cold that frost may travel down the stem to the tubers and kill them.
If possible choose a sunny, slightly windy day. Cut the tops off a few inches above the ground and toss in a
pile for later disposal. Some growers cut the tops off several days before digging, but this practice is not to
be recommended as there is too much chance for water, either resident in the remaining stem, or rain, to
seep down into the clump and promote rot. There is always the possibility of frost following down the open
stalk into the crown and starting rot there.
Try to have two people to dig, each equipped with a light, well sharpened shovel. A third person to grasp the
stalk and aid in lifting the clump, shake the extra soil off and gently set the clump aside, will aid materially in
saving tubers that might otherwise be damaged or ruined entirely. The important point is that all fine feeder
roots must be cut off all around the clump before endeavoring to lift it. Extreme care should be shown with
all long neck varieties to keep from straining or breaking the necks as the break will dry out clear through
and the tuber will be ruined. Set the clump to one side, carefully knocking off all loose earth possible,
inverting it to allow plant juices in the stem to drain out. It will pay to leave some soil around the slender
necked varieties to help prevent breakage. Some people like to use a frame with wire bottom set up on
boxes to set the clumps in to dry off. This permits free circulation of air on all sides of the clump.
The stalk should be cut off close to the clump and a tag firmly attached. The wire may be run through a tuber
if necessary or the name written on a large tuber with an indelible pencil. If digging must be done under wet
and muddy conditions, the clump should be washed off with the hose using a gentle pressure and the clump
thoroughly dried off before storing. If stored too wet with insufficient ventilation, and most storage rooms do
not have proper ventilation, much loss from rot may be expected. Some varieties have very heavy crowns
and coarse heavy tops and these should be split into two pieces before storing it aid in drying.
The above from Practical Dahlia Culture published by the Portland Dahlia Society in 1946
STORING DAHLIA TUBERS
By Ted J. Kennedy
Flash: Hollyhill Cotton Candy B IC DP won the Derrill W. Hart medal for "B" sized dahlias. Average score
A discussion on storing dahlia tubers for the more experienced grower.
Over the years, I have seen numerous discussions on how someone successfully stored their tubers using a
particular method. Then the next year or two later someone else tried this same method and it supposedly it
failed for that person. I have found that there are many factors that people may overlook concerning the
storage of dahlia tubers:
(1) Variety related issues; many varieties are prone to loss in storage. Barbarry Bingo is a wonderful dahlia
and an extremely poor keeper. Mingus Nicole is also very difficult to keep over. Why do these varieties fail
to store well? They appear to make reasonably good looking tubers. It is my belief that both of them are
susceptible to fungus infections that cause the tubers to rot. It may well be that the infection affects the
entire plant before the tubers are dug and that very little can be done with fungicide treatments after digging
and dividing. Or, maybe it is just plain bad genetics. These varieties may not have the ability to go
"dormant" in storage conditions. So, when you compare storage methods one must take into consideration
what varieties are being stored.
(2) Very few people talk about the the actual temperature and humidity levels in their storage area.
Temperature is an interesting issue. If a dahlia tuber has been properly prepared for storage, dahlias can be
stored at just about any temperature above freezing. But, the storage temperature has a lot to do with the
growth of insects and fungus. Insects do not generally thrive in cool temperatures. There needs to be some
research done on temperature as it affects these vectors. Humidity in the storage area is also another factor
that no one seems to talk about. Some areas are more humid and some climates are more humid during the
winter. I know of one grower who believes his overly humid storage area causes rot and has installed a
dehumidifier there. In the Northwest, more tubers are lost to too wet storage than too dry. In climates with
drier winters, there may some risk of too dry tubers. All in all, a little bit of too dry is probably better than a
little bit of too wet.
(3) Tubers that are not "ripe". In many show gardens, dahlias are grown with a more than an ample supply
of nutrients and water. When harvest time comes in the Fall, the plants are still growing and the newly
formed tubers are not good candidates for storage. They can be identified by their nearly transparent skin
and the fact that they are still rather skinny. Unripe dahlia tubers do not store well. They are much more
susceptible to bruising and their thin skin is easily damaged by handling and cleaning. When they are mixed
in with the more mature tubers, they can spread rot to tubers nearby. If you keep these tubers, store them in
a separate bag or box.
(4) Broken necks. Many dahlia varieties have thin necks where the tuber attaches to the stem. If the neck is
broken when you dig tubers, the tuber may look perfectly good but a very high percentage of these tubers
(90% is good estimate) will rot or fail to sprout. Many varieties are notorious for having long slender tubers
that easily get broken necks. Red Velvet and Jessica are two that come to mind. When digging these very
long tubers, it may be better to trim them to shorter lengths as you dig them. A tuber with about 1/3 of its
length cut off will store a lot better than a long skinny tuber with a broken neck.
(5) Curing of tubers before storage. I was surfing the internet and came across an article on how potato
growers prepare their tubers for storage. There are numerous steps that they go through just to get the
potatoes into a dormant stage. For example during digging and hauling to the storage area, potatoes are
bruised and skin is damaged. Potatoes need to have some time (two to three weeks) in reasonably warm and
dry conditions to heal these defects. Then they are slowly reduced in temperature before going into storage.
Do these steps apply to dahlias? I believe they do. After you harvest and divide tubers, they need to be in a
special environment to heal and go into the dormant state. It should not be too humid or too dry. The tubers
need to heal bruises and to have the skins thicken. When fully cured, storage success will be improved.
(6) How wet and cold is it when you are digging? In the Northwest, there may be weeks of rain during the
digging season. In Montana, the humidity may be very low. Dahlias need to be handled differently in
different conditions. In the Northwest, wet tuber clumps need to be divided very soon after digging. The wet
tubers need to be dried before storage.
(7) Peat Moss, vermiculite, cedar shavings, newspaper, perforated plastic bags, small plastic bags, saran
wrap, sand, wax, saw dust, etc. Dahlias have been successfully stored in all of these mediums and probably
many more. The medium itself may not be the answer but how you use the medium. No one talks much about
whether tubers are stored touching each other. I believe that separation of tubers from each other is as
important as the storage medium. For example, vermiculite can be used to separate the tubers in the storage
container. Saran wrap and the like does the same job with much reduced storage space. Separation of tubers
and the preservation of proper moisture in storage are key factors. But when using any of the storage
methods, a rotten tuber can create problems for other tubers in storage. It produces excess moisture and
even some gases that affect tubers in the same area. Rotten tubers probably attract insects. Rotten tubers
can harbor secondary bacterial and fungus that can spread to adjacent tubers. A good practice is to check
tubers in storage several times during the winter and to remove rotting tubers.
(8) Little attention is given to insect damage in storage. Very small insects such as fungus gnats and spring
tails lay eggs in tubers and the larva eat tuber parts. The green eye is very susceptible to such damage.
Prevention of infection is a good practice. If the weather is warm when digging, be aware of small flying
insects. Do not dry tuber clumps in an area such as a greenhouse where warm dry conditions encourage
insects. Using an insecticide dip may be very helpful. One grower fumigates his storage are with flea bombs.
(9) Pot tubers are insurance. Many varieties that have poor keeping tubers can be grown as “pot tubers” and
stored quite successfully. Generically, a pot tuber is an entire tuber clump of a dahlia that was grown in a pot
the entire year. The size of the pot can range from a gallon pot all the way down to a 2 inch pot. The bigger
the pot, the bigger clump will be. Commercial entities that sell pot tubers use small pots that are in the range
of 3 to 6 inches in width. In the Spring take a cutting or use a small tuber and grow it in a pot somewhere in
your garden. It can be placed on the soil in the garden or grown on a table or bench. They just need regular
water and a very little bit of liquid fertilizer. In the Fall, harvest your pot tubers before the first frost as they
are much more susceptible to freezing. Cut off the stem an inch or two above the pot and either store them in
the pot or out of the pot. I store mine in the pots.
November’s meeting will be the last regular meeting for this year. We will get together the second Tuesday
of December at our regular meeting spot for our annual Christmas Party. There will be a December issue of
the Bulletin around the first of December. There will be no Bulletin or meeting for the month of January and
our regular meeting and publication schedule will resume in February of 2010. Cut flower sellers please take
note… Burel and Shirley Bankston will be auctioning off their Flower Sale Cart at the April Auction as a
fundraiser for the 2012 National show. Bob and Myrtle Bloomfield wish to thank everyone for their cards,
calls and get well wishes. Myrtle will most likely be coming home later this month.
Sorbet will be the flower of the year at our next show.
Flower arrangements at our 2009 show. Theme was Pacific Trails.