Smilax

Are there any other smilax enthusiasts out there? In the old days this genus was included in the Liliaceae, but now it gets a family of its own, the Smilacaceae. Some are reviled as obnoxious weeds, some are hugely ornamental. The ones I grow range in size from little S. pumila and S. bifolia to mighty S. smallii which covers the side of our house and part of the roof, tangled with noisette roses and Campsis 'Mme Galen'. The smilax is the boss of that group.


Most species have black fruits, but S. walteri has very ornamental red fruits. It’s a treat to visit the black water swamps of the southeastern states during the winter and find broad tangles of this species spangled with the bright red fruits – but at first you’ll probably be tricked by the more numerous red-fruited deciduous hollies.

Some of the southern species flower regularly here and set fruit, but the resulting seed do not survive the winters here.

I’ve always liked these plants and had a few in the garden. It’s hard to find anyone else with much of an interest in them. Professional horticulturists in general neglect them, although in the early twentieth century no less a luminary than Beatrix Farrand used them on some of the walls of Princeton University (or so I recall reading).

Most I grow in the open, but little S. pumila gets cold frame treatment. Its mottled leaves (in the style of some Asarum) make it worth the space. It will survive indefinitely in the open here in a sheltered spot, but the fruit will not ripen in the open air and bad winters can damage the plant severely.

I’m training S. laurifolia onto the deck: so far, it has climbed to the 10’ level. Mature plants in the wild are awesome, like something out of some lost world fantasy. The canes sometimes go thirty or more feet straight up into trees – I assume they have grown up with the trees. I grew my plants from seed collected more than fifteen years ago after a storm had brought down some smilax festooned trees – otherwise I never would have been able to reach the seed. This species has great ornamental value but is almost completely neglected. The foliage suggests that of Clematis armandii or Holboellia – it’s a rare garden visitor who has any idea what it is. There is nothing else like it in our indigenous flora.

The flowers of S. smallii are sweetly fragrant. Other species such as S. herbacea smell of carrion. When I was a kid I used to think of S. herbacea as “hardy philodendron” – it resembles that house plant (the heart-leaf climber) a lot.

Are they geophytes? Some grow from clusters of banana like tuberous growths.

Sarsaparilla was (still is?) made from some tropical species.

In the photo above is little Smilax bifolia, which is small enough to be used, potted, as table decoration.

Cold frame treasures

In addition to bulbs, the cold frame houses a variety of other plants. Most of these are not suited to life in the open garden, and each represents a significant extension of my horticultural horizons in a new direction.

For example, there is a young seedling of Sophora secundiflora. In a very sheltered place, this might be hardy in the open. Mature plants have fragrant flowers which suggest wisteria. It’s a very handsome plant and all but unknown in gardens in this area.

A seemingly thriving plant of Cistus psilosepalus has me hoping that I might soon see a rock rose actually blooming in this garden. I’ve tried others in the open air, and they quickly went from bad to worse. Various cistus have been described as hardy in this area, but it’s not simply a question of hardiness in the sense of cold tolerance. The climate here is all wrong for them. The little seedling I planted into the ground in the cold frame has slowly grown all winter: it looks like it’s ready to take off once the weather moderates. The cistus I really want are the ones with fragrant foliage; if the current experiment proves to be successful, I’ll try one of those.

Several of the asarums are temporarily in the protected cold frame. These are Asarum nobilissimum and A. maximum. Last summer they grew in a spot which got plenty of sunlight and it seemed to do them good. I doubt if their foliage will have a chance in the open air, so they went into the cold frame for the winter.

There are also several rosemary plants; these were rooted from grocery store material sold for culinary purposes. Rosemary is like cistus: it’s not really hardy here in my experience, although an occasional plant might survive for years. Again, it’s not simply a matter of cold: the climate in general here is wrong for it.

Another occupant of the protected cold frame is little Smilax pumila. An earlier trial of this species in the open air was somewhat successful. The plants grew and went on to bloom – but the developing seed was killed by winter cold. I’m hoping that they will be right at home in the protected frame.

Ceratostigma griffithii occupies a corner of the cold frame. I doubt if this plant needs cold frame protection, but at the time the frame was built the Ceratostigma was still in a pot and needed a home. Because it blooms so late in the year, the frame seemed to be a good choice. It has made itself right at home.

Ruscus hypoglossum is also spending the winter in the frame. I expect this to be hardy in the garden, but I have not yet decided where to put it.

There is also a little plant of Calluna vulgaris ‘Mrs. Ronald Gray’: this is there to remind me of my plan to grow a variety of little evergreen shrubs in a cold frame. Heaths, heathers and broadleaf evergreens have never become common in our gardens; I think the main reason for this is that they experience so much foliar damage that they emerge from the winter ugly. Cold frame protection should prevent that.