While reliable dwarfs should be chosen for the main area of the rock garden, conifers with an ultimate height of 4 to 6ft(i.25 to 2m) can provide a first-rate backcloth. Among the truly dwarf conifers are a range of diminutive bun-shaped cultivars which are best grown in an alpine house; outdoors, the very tight growth is often disfigured by frost and winter wet. A "mini pinetum", a collection of dwarf and slow-growing conifers selected for their diverse form and colour would provide a very fine, and labour-saving, feature for the garden. Again care should be taken to plant conifers of appropriate size for the allotted space. While a natural, informal planting is, desirable such a collection of conifers could well be presented in the more formal setting of a large bed or border. In both cases dwarf shrubs and sun-loving ground-cover could be used in association with the conifers to good effect. There are no more suitable associates for heathers than dwarf and slow-growing forms of conifers. Heathers are essentially plants for full exposure and most conifers also provide their best form and colour in similar conditions. Conifer species and cultivars of irregular shape are more suitable for the heather garden than those with a formal outline. There is always much interest in plants suitable for ground-cover and here again there are a good range of conifers which are suitable. The robust, spreading junipers (see pp.60 and 61, and Chapter 12, "Ground-Cover Plants", pp.129 t° 137) are good examples of those conifers which provide dense and attractive ground-cover. This type of conifer is more than capable of choking weed growth and covering effectively unsightly banks, drain covers and the like. The Taller Conifers Still on the theme of conifers for the smaller garden, only those attaining a reasonably narrow form and ultimate height of 5oft(i5m) will be considered. Again, the uses are numerous with the taller conifers of quality making superb specimens for important positions; companion evergreen trees for mixed plantings; and effective screens and hedges, for which last purpose there is no better choice of planting material. Apropos the ultimate size of the chosen conifer. It is very important to be most careful in this matter-or is it? Do remember that your perfect lawn specimen of 3oft(9m), while it may fit the scene perfectly at that height (because it is a comparatively small tree when fully grown) will take a life-time to attain that height. In view of this, a conifer may be chosen for the position just described which is faster growing and will provide the desired effect in perhaps half the waiting period. It is possible that the faster-growing specimen will have to be removed eventually, but far more pleasure for a far longer period will have been obtained. Clearly, a careful choice has to be made; no one would recommend a giant redwood, Sequoia sempervirens, for growing in a limited space, and we have all seen those Victorian monkey puzzles, Araucaria araucana, growing a few feet from a house! Choosing and Planting Conifers Great care should be taken when choosing conifers from nurseries and garden centres.