McCaskill Alpine Garden, Lincoln College : a collection of high country native plants

Abstract

The garden, named after the founding Director of the Tussock Grasslands and Mountain Lands Institute, is intended to be educational. From the early 1970s, a small garden plot provided a touch of character to the original Institute building, but it was in 1979 that planning began to really make headway. Landscape students at the College carried out design projects, ideas were selected and developed by Landscape architecture staff in the Department of Horticulture, Landscape and Parks, and the College approved the proposals. Construction was completed in time for spring plantings in the same year. The garden is a collection of plants to provide not only an atmosphere of natural grassland and mountain herb field, but also to attract attention to the plants that make up those associations. Because many plants are small and rather hidden among the large dominant species, a sense of atmosphere ('being among the tussocks') is of itself unlikely to draw attention to the fascinating denizens of the nooks and crannies. As has always been true, many people climb mountains and tramp through the open country without ever putting their noses to the carpet of plants at their feet. In our educational garden, the beds are therefore raised high, and no point is far from the pathway. In addition, seating enables you to view the plants at eye level. Many alpine plants demand a good supply of moisture and yet cannot withstand 'wet feet'. On mountain slopes, sub-surface water is always on the move down the slope, and so the plant is supplied without any pooling effects around its roots. In this raised garden, good drainage is provided to achieve this. There are heavy layers of gravel below the soil and a gritty mix throughout the soil. The large rocks in the garden are greywacke, and were selected from an alpine area for their form and lichen covering. The rocks create a focal point and are intended to give a sense of 'altitude' within the garden. In the centre bed, rock scree is spread over the surface to create a pavement of broken stone, and at the same time, a mulch giving a cool root run. Plant distributions are in a radial pattern around the focal rocks. Like the spokes of a wheel, they extend across pathways to the outer beds. There are seven groupings, representing the geographic spread of seven regions of the New Zealand native grassland flora. The regions and a diagram of their location in the garden are listed on page 36. Typical plants of each region were sought, and especially those that help to make the regions distinctive. The collection therefore, includes the physiognomic dominants - the larger plants that confer on a vegetation its basic form and appearance. A tall tussock grassland is very different from a short tussock grassland, although some plant species may be common to each. The same species of tussocks and mountain daisies, for example, may therefore be found growing in different regional areas in the garden. The inclusion of shrubs and small trees is a recognition that grasslands and herb fields are frequently integrated with other vegetation types. The woody species furthermore, add greatly to the landscaping use of texture, form and height within the garden. Below the vegetation canopy are the less obvious plants - diverse in their growth form and habits - cushion plants, herbs, and mats. Like all gardens, ours requires regular weeding and care is necessary that some alpine plants themselves do not become weeds by outgrowing the less vigorous species. In the summer months, regular nightly watering is controlled by an automatic sprinkler system. Line drawings by Pat Prendergast are intended as impressions of plants in the garden and should not be used elsewhere for reliable species identifications. Many of the original sketches were made in the garden itself, as plants flowered and attracted attention during the succession of seasonal changes. Others were done in the field, but illustrate plants included in the garden. The text has been written by Joy Talbot, a botanist. The emphasis is on relationships - the meanings behind the names, the natural habitats of plants (abbreviated as 'Ha' in the text) and geographic distributions (abbreviated as 'Di' in the text). The relationships between genera and the families in which they are grouped is alphabetically arranged in the annotated index. To find information on the genus of an illustrated plant, first look alphabetically for the family name. For example, to find the meaning and relationships of Celmisia, look under the family name Compositae (Daisy family), shown with the illustration for any of the Celmisia species.