Five favorite yellow-flowered geophytes

Jim McKenney
Wed, 21 Jan 2004 18:11:15 PST
Jim Shields wrote
>I don't know where Jim McKenney lives and gardens, but it's for sure warmer 
>than here, if Hymenocallis 'Sulphur Queen' survives outdoors in the ground.

Years of experience have shown that a wide range of "tender" plants which
remain dormant will survive outside against a wall here. By "against a
wall" I mean right up against the foundation of the house on the sunny side
(and, in this garden, that's the side where the house heater is).
Apparently it does not freeze there. 

Plants which attempt to grow in cold weather (lots of very desirable plants
from the southern hemisphere) on the other hand are hopeless outside.
Amaryllis belladonna is a good example. It keeps pushing up new foliage all
winter; and the new foliage is destroyed soon after it emerges. 

The widely available yellow Lycoris behaves the same way. At the end of
even a severe winter the bulbs are fine; but the foliage doesn't have a
chance. The plants dwindle and eventually disappear unless helped. 

One improbable (and off-topic, my apologies) success story: Brugmansia
Charles Grimaldi. It's been outside for six years. By the end of August
it's seven or eight feet high. Once nights begin to cool off a bit it
starts to bloom: that's something to see!

Some Gloriosa and Eucomis tolerate this treatment, too. And I've had
friends tell me it works for some hybrid Hippeastrum. 

How cold does it get here? In a really bad year, it may briefly go down to
zero F for a few hours. Almost every winter brings a few very cold mornings
with temperatures in the 0-10 degrees F range. And we sometimes experience
fairly long periods when the daytime temperatures do not go above freezing
and things really freeze up tight. 

This reminds me of when I was a kid and always reading British gardening
books;  I would see a reference such as "we experienced 5 degrees of frost"
and think (wishful thinking if ever) it meant 5 degrees F. I killed a few
plants until I figured out the British system.   

Just to be sure no one misunderstands: Hymenocallis Sulphur Queen would not
have a chance outside in the open ground during even a mild winter here.
But the microclimate right against a wall is a different world. 

BTW Jim, I think I bought some Hymenocallis hybrids (the Korsakoff hybrids
Pax, Helios and Icon or Icarus or something like that) from you about
fifteen or twenty years ago. Shortly after, you experienced a big freeze
and lost a lot of plants - and I thought you were no longer in business.
Does that sound familiar? If so, it's a small world, isn't it!

Jim McKenney
Montgomery County, Maryland, zone 7, where Hamamelis x intermedia Pallida
is also blooming (or trying to) but the real action is under the lights
with the germinating seedlings.

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