In a message dated 6/14/1999 3:36:31 PM US Eastern Standard Time,
<< The other varieties I have trouble overwintering include Colocasia
"burgandy stem" and C. fontanesii. >>
Here's a tip Les might be interested in and that many other Zone 5 to 7
people might find useful.
I have found that I can overwinter plants that are hardy to Zone 7, [this
being Zone 5b] by cramming a styrofoam rose cone with coarsely shredded wood
shavings --- packing materials that come in and that I save for this purpose
--- and putting the rose cone over the plant in the garden that I want to
This has worked for lemon verbena, and has also worked very well with
Helleborus argutifolius and H. x sternii, both rated Zone 7. Those
hellebores [plants about 12 inches tall when I covered them *at the last
possible minute* (and ice coated at that)] are now more than twice the size,
and blooming prolifically! The one I missed because I ran out of cones died
back to the ground, but has come back and is about 6 - 8 inches tall.
Styrofoam rose cones are available in the plant section of most hardware
stores like Ace Hardware or "mega stores". Here is a Meijer Thrifty Acres,
although there it could be a KMart or other store where groceries, clothing,
housewares, garden supplies are sold, or a Home Depot. They sell two or three
different sizes of styrofoam cones [they look like the orange cones used by
highway repairmen, only lots larger and they are white styrofoam -- to match
the snow, I guess ; - ) ]. They usually start carrying them about October
I always buy the largest size. For added insulation, [if the size of your
plant permits, and especially when dealing with something like Dranunculus,
which would be dormant and cut back above ground] you can pack the inside
with the coarsely shredded wood shavings, as I previously mentioned. Or take
plastic grocery bags and stuff them with saved styrofoam peanuts and tie them
shut. Use some kind of tape to hold this stuff up in the top of the cone,
leave room for any plant material above ground. Place over the plant [or the
place where the dormant tuber is] and weight down so it doesn't blow away or
get knocked over by any varmint.
I add two (at least) Zones of protection to less hardy plants in this manner.
I think I'm going to try this with some, but not all, of the Arisaema
griffithii this year. [I ended up with 12 -- don't ask why] and they are
only supposed to by hardy to Zone 7. Even though the A. kiushianum I
"mispaced" wintered over and bloomed just fine, I wonder about these
griffithii and also the A. erubescens. It'll either be a 2 inch depth and
lots of straw or a rose cone.
Now that I've gotten the Helleborus argutifolius and H. x sternii through two
winters, much to Ellen Hornig's tremendous surprise, -- last year with
extremely cold Arctic weather and no snow cover was a challenge -- I guess I
will have build a larger and similar containment for them.
I have used the same method to overwinter pineapple sage [cannot remember the
botanical name, but its an herb of the mint family, again Zone 7 - 9]. That,
I cut back to the ground and then covered.
Perhaps this would work for your Colocasia "burgandy stem" and C. fontanesii.
At any rate, Les, thanks for your comments on the Colocasia. I see this
arriving at a garden *near* me next spring!