There is no more iconic symbol of the Christmas season than holly — Ilex aquifolium, that is, sometimes called English or European holly. But today, florists also have at their disposal a new Christmas classic: winterberry, or deciduous ilex (I. verticillata), also called simply ilex.
Belonging to the same genus, holly and ilex share a signature holiday look with their bright red berries. As with so many siblings, however, the outer resemblance goes only so far.
Most strikingly, while holly is known for its glossy foliage, Ilex verticillata loses its leaves early on (that, of course, is what “deciduous” means) — with the result that its rich berry clusters are exposed on bare twigs, for a vividly monochromatic and contemporary look. Growers typically remove any remaining leaves at harvest time, since the leaves will fade and drop long before the berries do. (If any leaves remain when the branches arrive in the shop, you should remove them yourself.)
Ilex has been on the market for at least 40 years, initially as a Dutch import. It thrives, however, on the West Coast, where a range of sturdy and design-worthy new varieties has been developed within the past decade at Sun Valley Floral Farms. Some of these come in autumn shades of gold and salmon, as well as in brilliant orange for Halloween. The season begins with the fall tones as early as September and swings into red by early to mid November. Stem lengths range from 16 to 40 inches.
Pros and Cons
Another big difference between holly and ilex — not so evident to the eye — is that while holly was always the problem child among Christmas greens, ilex is far less so. Berried branches, in general, offer a much longer vase life than most cut flowers. The flip side is that, bearing fruit, they also produce ethylene, which can hasten maturity, especially in ethylene-sensitive plant materials.
In the case of berried branches, ethylene exposure can cause berries to wrinkle and drop or to soften and decay, depending on hydration and humidity. The good news is that while holly is known to be ethylene-sensitive, ilex is not especially so. You may wish to ask holly suppliers if their product has been treated at the grower level with an anti-ethylene product.
Steps to Healthy Holly and Ilex
For both holly and ilex, here’s what to do at the retail level:
- Purchase holly or ilex with plump, unwrinkled berries that show no sign of discoloration.
- In the shop, open the boxes or bags immediately to dispel any ethylene gas inside.
Both holly and ilex may be shipped in plastic bags or in boxes lined with plastic in order to keep the berries from drying out. In the past, retailers often stored cut holly dry, but still covered in plastic. The risk was that condensation of moisture beneath the plastic could encourage the growth of botrytis mold. Therefore:
- In the case of both holly and ilex, the best practice is to unpack, cut and hydrate the stems and to store them uncovered in a cooler with high humidity, cool temperatures and good air circulation. The latter two environmental conditions are key to avoiding botrytis along with the damaging effects of ethylene.
- Note that while many shop coolers are kept at 38-40 F, cooler temps of 33-34 can double the safe storage time of berried branches — in the case of holly, from three to six weeks; even longer with ilex.
- As with any berried branches, it’s best to let the cut stems drink from a holding solution, engineered to keep water flowing through the stem via low pH and antibacterial action, versus a vase solution, which contains a fuller complement of nutrients, meant to encourage cut flowers to open and color up. When combining ilex or holly with cut flowers, however, a vase solution will do no harm.
Bruce Wright is a contributing writer for Floral Management.