Holly decision hangs heavy after the
holidays
Tell us about what to do with live plants like this
lovely little holly (with fake berries) that I received at a
luncheon. Should it be put into the ground and be protected
with a pile of leaves or peat moss or something or should I be
content just enjoying its temporary beauty? - G.D. -
Meant to brighten the holidays
You can go either way. Such pot crops are produced by the
gazillions, intended to be decorative but disposable. (Well, maybe
not gazillions but by the hundred thousands, anyway; see Pot
Crops.) So deciding to simply compost it is okay. You have no
obligation to conserve it as a rare and endangered item.
Hollies: They are eye candy, but also stomach
trouble, a pruning challenge, and
they make a needy house guest... why do we love them so
much?! 
Right: A gift holly in a pot should not be faulted for
bearing fake berries. It's tough, if not impossible, to induce such
a small plant to flower and fruit.
Can be kept and grown on
However, if you want to keep it you will have to gradually
acclimate it to outdoors. Plants that have known only the mild
temperatures of a greenhouse or home haven't acquired any hardiness
and can't, now, if suddenly thrust into air that drops below
freezing every day.
Before it could handle the outdoors it would need at least a
couple of weeks in autumnal, cold-but-not-freezing air and good
light. (Light's essential because hardening of cells requires
energy.) Without that hardening time, the plant's cells may freeze
and burst. It would lose leaves, twigs, even roots. (More in How long to
harden off.)
To reacclimate it, put it out for
at least a few hours every day of its two week transition, at times
when it's over 40°F. During frigid hours, bring it back in to a
cool place indoors. If it's small, stashing it in the refrigerator
is an option. Another option is to put it in a cold room in good
light and let it to spend the winter there. Or give it a few weeks
in the cold room, then move it to a cold-but-above-freezing garage,
shed or cellar for the rest of the winter.
May not rate a place in your garden
The twist to this story is that only a few of the 400 known
holly species are hardy enough to thrive in the northern part of
North America. If the plant you've been given is not hardy in your
zone, it does not matter whether you keep it alive indoors or do
heroic things to acclimate and protect it outside through the worst
of this winter -- because it will die next winter.
Of traditional hollies that are evergreen, with
spiny leaves and red berries:
- The Meserve hybrids are in the
hardy minority. I. x meserveaeinherited good looks from
one parent and hardiness from the other. Varieties widely used in
zone 5 landscapes are 'Blue Prince' and 'Blue Princess'.
- The Chinese hollies (I. cornuta) are
marginal in general ( zone 5-6), with a few hardier exceptions such
as 'China Girl' and 'China Boy' which p ersist even in warm zone 4
as long as all other growing conditions are good.
- American tree holly (I. opaca) is
also hardy to zone 5 but doesn 't fare well where it faces wind as
well as cold, so it is not grown as often in the north as the
Meserve hybrids and Chinese holly.
- The traditional English holly, I.
aquifolium and its hundreds of varieties, isn't hardy anywhere
colder than zone 7 and also needs the cool summers and moisture of
maritime climates -- such as in northwest Europe where it's native.
So we see it in the U.S./Canadian Pacific Northwest and sometimes
along the coast in mid-Atlantic States.
Yet some of the best hollies for greenhouse pot crops are
cultivars of English holly, so they're widely grown as holiday gift
plants.
We would love to grow some of the variegated English hollies
in our zone 5/6 gardens. We've tried but must report "no go" even
in those places w
e work which are a solid zone 6. We
courted Ilex aquifolium 'Silver Queen' most
royally
and made some stabs at the likes of Ilex aquifolium
'Marmorata,' at right. (If you don't see such plants at your
local garden center, we're not surprised. There are many thousands
of plant varieties in cultivation and no one seller can offer all
of them. One
place we order some of our unusual hollies from is
Forestfarm.
Jump to their site from our Recommended Sources page.)
The upshot of all of this?
Those of us in zone 5 and colder areas who need to know if it's
hardy should hope for a label with the species name. Alternatively,
we can read the leaves (below) to guess the species.
