Planting a Terrace Garden

Planting a Terrace Garden

by

A. R, BUCKLEY,

The Plant Research Institute, Ottawa.

The terrace or patio garden is the center of interest all summer and fall. It should, therefore, be planned carefully as to location, construction and planting.

A well-placed terrace in harmony with the house has, a real estate value far greater than its cost of construction. Technically, a terrace garden as its name suggests is an area raised above ground level, and a patio is, (in modem usage), an outside area enclosed by walls, but this doesn't always follow. Both types are often referred to as patios whereas the term terrace would be more apt whether the garden be at the same level as the lawn or a few steps higher.

An enclosure should be made with walls, hedges or small, neat shrubs and outlets leading from it to open up vistas beyond. The patio need not be too elaborate but surfaced with gravel or stone set in sod and bordered with a simple selection of plants. It should be an extension of the living quarters and a vantage point from which to view all angles of the garden.

Hedges to enclose the terrace garden should be small and slow-growing. The Japanese yew (Taxus cuspidata) or Korean box (Buxus microphylla var Koreana) are two suitable evergreens for this purpose. The dwarf snowball (Viburnum opulus 'Nana'), or Arctic willow (Salix purpurea 'Gracilis') which grow taller, are not too coarse and lend distinction of foliage to the garden.

In front of the hedge a small narrow bed is often left. This should be planted with a small ground cover such as periwinkle (Vinca major), Japanese spurge (Pachysandra terminalis), or bearberry (Arctostaphyllos Uva-ursi). Among these plants, set small flowered spring bulbs such as Siberian squill, grape hyacinths, and miniature narcissis where they are hardy.

When constructing the terrace, leave spaces for good specimen plants or group plantings. This garden calls for formal exotic plants some of which may be planted in tubs and stood in strategic places. Plants such as the dwarf Alberta spruce (Picea glauca 'Conica'), hostas and daphnes may be planted here in groups.

In the tubs grow tender plants like the blue hydrangeas, English Holly or bay laurel. These must be transferred to the basement for the winter and kept fairly dry in areas outside the milder part of British Columbia.

If the terrace is laid on good sandy soil, small rock plants may be used for the crevices between the stones. They add color and often form mats of two or three feet in diameter and will withstand a certain amount of traffic. The best plants for this purpose are Arenaria verna, Thymus serpyllum and its cultivars, Veronica repens, Phlox subulata and little mounds of Sagina repens.

The annual sweet alyssum in its small compact forms, such as 'Carpet of Snow', may be seeded right into the crevices. If the location is hot and sunny try the annual ice plants (Mesembryanthemum) and single or double portulacca.

It is a matter of some discussion whether planting in the crevices of flagstones or slabs is desirable or not. True, the end result if properly carried out is interesting and extremely beautiful. The argument against plants set in flagstones comes mainly from visitors who feel they have to tread very carefully to avoid stepping on them even though told they will withstand it. Grass between small flagstones may be mown with the lawn mower if the stones have been set in properly, but it tends to grow into uneven clumps and looks weedy.

At the other side of the terrace wall or hedge, another planting must be made. Here low spreading evergreens intermixed with interesting neat flowering shrubs are advisable. What could be better in such a location than the very early shrubs that flower almost as soon as the. snow disappears and when the rest of the garden is muddy and dreary?

The lovely waxy white flowers of the White Mezereon (Daphne mezereum 'Album') are usually lost in a shrub border. But in- this location they would be admired while the snow still stands on other parts of the garden.

The Korean Golden Bells (Forsythia ovata) would give a garden picture of its own in early spring and the dwarf Anthony Waterer spire a (Spiraea bumalda 'Anthony Waterer') with Lemoine's deutzia (Deutzia lemoinei) could follow later. The terrace garden usually extends from the kitchen back door or a porch may provide easy access to these early shrubs.

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