PLANTING 



PLANTING 



2675 



the size of peas. Their susceptibility to decay at the 

 surface is comparable to the damping-off of seedlings. 

 The mulch of gravel is invaluable in remedying both 

 maladies. Keep the soil moist but never saturated, and 

 do not permit the roots to become excessively dry. 

 This treatment will insure good continuous healthy 



trowth and, in autumn, a reward of many attractive 

 owers. The other genera require like treatment. 

 G raft ing of genera and species is easily effected but of 

 no special cultural value. Owing to the highly special- 

 ized structure of the flower in Asclepiadacea?, it has 

 thus far been impossible to effect artificial pollination, 

 although natural hybrids, through the agency of flies, 

 are very common. This is especially true in stapelias. 

 Bigeneric hybrids have been reported. 



Dyckia and hechtia of the Bromeliaceae and yucca, 

 and the aloe group of the Liliaceae, should receive the 

 same treatment as agave. The species are more com- 

 monly propagated by seeds, and the hybrids by division 

 and stem-cuttings or division of the crown. Senecio 

 (Kleinia), of the Compositae, may be propagated either 

 by seeds or by cuttings. With them, also, grafting is 

 Possible. C. H. THOMPSON. 



Topiary planting and garden architecture. 



Topiary work includes sheared hedges, pollarded 

 trees, clipped individual shrubs, whether shaped into 

 simple, rounded, or pointed form, or into more elaborate 

 designs. It includes the trimming of masses of foliage 

 into the form of birds, beasts, furniture, architecture, 

 and other conceits. The more intricate designs are 

 usually attempted in evergreen plants. ^-Garden 

 architecture comprises all structural or architectural 

 elements introduced into the landscape except the 

 main buildings that are to serve the primary uses of a 

 property. This definition thus includes all walls, 

 trellages, posts, gates, pavilions, exedras, loggias, per- 

 golas, shelters, fountains, bridges, seats, pavements; 

 closely related with it are garden and lawn ornaments 

 and furniture, such as statuary, vases, urns, dials, 

 bird-fountains, lanterns, and the like. It includes the 

 plain, the simple, and the rustic, as well as the more 

 elaborate, ambitious, or ornate. Virtually all of the 

 historical architectural styles are represented or 

 suggested in the forms of garden architecture. For 

 interesting illustrations and discussions of these sub- 

 jects, the reader should consult Blomfield and Thomas, 

 ''The Formal Garden" (London), from which Figs. 

 3018 to 3023 are adapted. Compare, also, Fig. 3025. 

 Fig. 3024 shows a common form of vase, used not so 

 much for its architectural placing as for a receptacle 

 in which to grow flowers. 



Topiary and garden architecture, although distinct 

 and separate, are nevertheless essentially related, both 

 in origin and in use. Both have their inception in the 

 virtually universal formality of all early landscape 

 design, and historically and at the present day they 

 frequently stand side by side as related elements of a 

 design. 



For many centuries gardening was conducted behind 

 inclosing and protecting walls, a practice made neces- 

 sary by the uncivilized conditions. In general, such 

 inclosed gardens were rectangular or geometrically 

 regular, and comparatively small. They existed in 

 immediate proximity to the owner's dwelling or adjacent 

 to the building. The necessity of conserving ground and 

 of utilizing it most efficiently lead naturally to arrange- 

 ment and planting in straight lines and rows. Utility 

 having thus first determined a regular arrangement of 

 plant-materials in close proximity to architecture, 

 esthetic composition, in its turn, attracted the attention 

 of more cultured man and formal design in landscape 

 gradually evolved. 



Both garden architecture and topiary are attributes 

 of the formal in landscape design, which is determined 



by lines, axes, and balance of parts. The inappropriate 

 use of either results in inharmonious and bad design 

 and constitutes an esthetic abuse. 



The following plants are well adapted to topiary 

 treatment : 



N'OTE: E means plants evergreen. 



P means plant must be protected in climate of Boston. 

 S means plant is semi-evergreen. 



Acer campestre. 



Acer platanoides var. globosuni. 



Berberis Thunbergii. 

 E Buxus japonica. 

 EP Buxus sempervirens. 



Carpinus Betulus. 



Carpinus Betulus var. globosa. 



Catalpa bignonioides var. nana (=C. Bungei in the trade 

 but not the true C. Bungei from northern China). A 

 dwarf variety of the southern catalpa often grafted high 

 on upright stem. 

 E Chamsecyparis nootkatensis. 

 E Chamaecyparis obtusa var. nana (=Retinispora in the trade). 



Cornus mas. 



Cratsegus Oxyaeantha. 



Evonymus alata. 

 E Evonymus radicans. 

 EP Ilex crenata. (A small-leaved variety of this has grown in the 



Arnold Arboretum at Boston entirely unprotected.) 

 E Ilex glabra. 



Ligustrum Ibota. 



Ligustrum Ibote var. Regelianum. 

 PS Ligustrum ovalifolium. 

 S Ligustrum vulgare. 

 E Picea excelsa. 

 E Picea orientalis. 

 E Pinus Cembra. 

 E Pinus densiflora var. pumila. 

 E Pinus montana. 

 E Pinus montana var. Mughus. 

 E Rhamnus cathartica. 

 E Taxus cuspidata. 

 E Taxus cuspidata var. brevifolia. 

 E Tsuga canadensis. 



Viburnum Opulus var. nanum. 



Viburnum prunifolium. 



In the growing of the plants for topiary use, no 

 special care is required except to be sure that the 

 plants are well grown in the nursery, vigorous, and 

 naturally thick-topped and fine-twigged. If the piece 



3019. A wall inclosure of topiary work. 



is to be a hedge or continuous line, the plants should 

 be very uniform in size and vigor when set and the 

 ground should be prepared in uniform condition so that 

 all the subjects will have equal chance. The plants 

 should be set close together. Clipping should be begun 

 soon after the plants are established to keep them close 

 and to develop and preserve the side and lower branches; 

 and the clipping should be practised several times each 

 year. If the plants once overgrow, so that they become 

 open and scraggly below, they can never be brought 

 into good condition. Great care must be exercised to 

 see that insects and disease do not get started, and 

 that the plants suffer neither from drought nor wet 

 feet and that they are well supplied with nourishment. 

 See Hedges. 



