Hard to let a cute little holly go

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.

Any holly can be your house guest but only some can live outdoors year-round in USDA hardiness zone 6 and colder. This is a Chinese holly hybrid that can manage in zone 5. Chinese holly leaves have particularly stiff, sharp spines. Flowers with prominent button center and no pollen mark this as a female plant.

Any holly can be your house guest but only some can live outdoors year-round in USDA hardiness zone 6 and colder. This is a Chinese holly hybrid that can manage in zone 5. Chinese holly leaves have particularly stiff, sharp spines. Flowers with prominent button center and no pollen mark this as a female plant.

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?!

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.

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.

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.

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 we 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.