This section is from the book "The Gardener V2", by William Thomson. Also available from Amazon: The New Organic Grower: A Master's Manual of Tools and Techniques for the Home and Market Gardener.
The "Ivy " can be traced back to very early times, when it is said to have been used at religious ceremonies, and as garlands on festive occasions, and it is still used less or more for similar purposes. The present few remarks are more in favour of its more extensive use in flower-gardens, where the many distinct varieties can be planted as permanent edgings for covering stumps of trees, or under trees where little else will grow. There is now such a diversity of colours and shades amongst Ivies, that when much winter and spring bedding is to be done, they will be found indispensable; and many of them, when covering the space allotted to them, will stand comparison with some of the variegated Geraniums for effective display. All the green varieties do well when planted in good rich soil; but if many of the variegated ones are put into too rich soil they are apt to grow too strong, when the variegation is neither so pure nor so extensive. A little lime-rubbish mixed amongst the soil will be found beneficial in bringing out the variegation. "We find them more satisfactory than any of the general bedding-plants for inner courtyards.
Where the sun is entirely excluded, the Geraniums, etc, make plenty of growth but scarcely any flowers: the Ivies are quite at home in shade, and are very effective when looked down upon from windows and balconies. One great recommendation is, that they are always the same at all seasons. An edging eighteen inches wide, with a centre of some other variety, is very effective. They will require frequent attention to keep the shoots from running into each other, for if this is allowed, the effect is not so good. It appears, also, to be at home amongst petrified stone, of which we have several beds, where they are more exposed to the sun. These beds are raised above the ground level considerably with the stone, and the crevices filled up with soil. Each bed is planted with a distinct sort. The green varieties have a light-coloured flowering Clematis, and the variegated sorts have a dark Clematis planted along with them; when, in a few years, all get strong and into good condition, they are expected to be very effective.
The blooms of the Clematis ought to show well on the bed of Ivies; in winter they can be pruned in a little, when a few minutes will soon cover the shoots that are left by putting them down amongst the Ivy. When grown in beds they should never be allowed to straggle, but keep all shoots closely pegged in their proper place. Many, if not most of these Ivies, can be grown in pots with little or no trouble. By having a collection of the best sorts, they can be used to great advantage in the flower-beds in winter, where they make grand centres for large beds; and as single specimens, large plants can be grown in medium-sized pots, and will require little else for several years but a slight top-dressing when removed from the beds in spring to be plunged in their summer quarters, which should be where the mid-day sun cannot reach them, in which position the colours of some of them are richer. For walls having north aspects, nothing looks so well, taking all the season through, as a good collection of Ivies when carefully planted for effect.
If they were of recent introduction, there would have been a great stir made about them: although many of the finer kinds are new, still, you will hear it said, they are but "Ivies." The first time we saw a good collection was at Wimbledon, where they were planted to cover pillars of a boundary walk, when we were quite taken with them, and so would any one, unless thoroughly prejudiced against them. The names of a few may not be out of place: -
Algeriensis, fine strong growing, with large green foliage: it makes a good pot-plant, soon getting to a large size.
Canariensis, large green-leaved sort, rick glossy colour, very free growing.
Canariensis marmorata alba. This is a fine silver variegated variety. The young leaves sometimes all of a silvery cloud, while others are mottled on a green ground. We had an edging of this 18 inches wide round a bed last year, rilled in with East Lothian purple stock, which was much admired.
Canariensis aurea maculata, resembles the previous one in growth, beautiful golden variegation.
Csenwoviliana, beautiful small cut leaf, light green, runs freely, and should be in every collection.
Donerailense, very small, beautiful cut leaf.
Clouded Gold is another fine effective variety.
Digitata, dark-green foliage, free grower, and good pot variety.
Cavendishii, smallish leaf, centre parts of a dull green, the edge beautiful silver grey; a very pretty pot-plant.
A urea densa, fine variegation, good for pots.
Aurea maculata, sometimes nearly a whole shoot of one year's growth will come silvery white.
Marginata Cullisi should be in all collections; either as a wall plant or for edgings it is unequalled. Palmata, beautiful golden variegation.
Rhombea, another fine silver-edged sort.
Raegneriana, Sagitefolia, and several more, should not "be neglected if a good collection is wanted. There are several varieties very much alike, which should not be neglected, as a good assortment cannot be had without a few resembling each other a little. Those that are more properly designated " Tree," or " Bush Ivies," are more slow growers in a general way; but nice young healthy plants, with proper care and attention, soon form handsome little trees; several of them bear berries in winter, which adds greatly to their appearance and value as a winter decoration plant. There are a good many in this section, but 12 or 15 of the most distinct varieties are ample. When the real value of Ivies is found out, they cannot fail to be more extensively used; and no doubt some one will take them up, and, judging from what has been done amongst them the last few years, will bring them to as great perfection as the Golden and Bronze Geraniums. Edgings in winter and spring of a Mrs Pollock-like Ivy, with Imperial Blue Pansy, is not too much to hope for.