1104 ARBORETUM AND FRUTICETUM. PART III. 
When Cape heaths are planted out, either against an open wall, or on a bed 
to be protected during winter, the soil should be previously prepared, mixed 
with stones, and placed on a substratum of drainage, in conformity with Mr. 
M‘Nab’s directions for preparing the soil, and growing and managing heaths 
in pots. The plants turned out should, at least, be of four or five years’ 
growth ; because it is found from experience, that stout plants of half-hardy 
species of every kind of shrub will bear more cold the first winter, when 
planted in the open ground, than weak plants. As heaths require a free cir- 
culation of air around them at all seasons, they will probably succeed better 
when planted in a bed of soil in the open garden, and protected by a movable 
roof, than when planted against a wall: but this movable roof must consist 
chiefly of glass, on account of many of the species being in a growing and 
flowering state during the winter season. We have no doubt that, in various 
parts of the south of England, most of the sorts enumerated in App. IIL, if 
thoroughly established in the open ground, would require no protection what- 
ever. The branches would exclude the frost from the soil; and, if the tops 
were occasionally killed down to within 2 ft. or 3ft. of the roots, the plants 
would spring out again the following season, and soon recover what they had 
lost. The south-east side of a natural hill would be the most suitable situa- 
tion for such an ericetum, provided care were taken in early spring, when the 
plants were covered in the morning with hoarfrost, to thaw it off by watering” 
them before sunrise ; but, in situations where this precaution cannot be attended 
to, a south-west aspect would be preferable. In the Gardener’s Magazine, vol, 
i. p. 374., we have suggested the idea of planting the Cape heaths in suitable 
soils in the open garden, and covering them, during six months in the year, by 
a glass roof, supported by movable iron props, which might fit into fixed 
sockets, so as to show no vestige of the structure during summer, when 
it was removed. The heat might be conveyed, by flues or steam-pipes, under 
the paths. At Woburn, many of the duplicates of the Cape heaths, which 
are kept under glass during winter, are turned out into the parterre of hardy 
heaths during summer, “ where they generally flower, grow vigorously, and 
form themselves into handsome bushy plants.” The tenderest and most 
difficult to propagate of these are taken up in autumn, repotted, and replaced 
in the heathery ; while the more hardy and easily propagated species are 
suffered to remain till they are destroyed by frost, or to take their chance of 
the winter proving mild ; in which case they survive it. EH. Actz‘a, E. triflora, 
and £. floribanda stood out during two winters at Woburn, though there 
were 14° of frost. (Hort. Wob., p. 283.) Mr. Robertson of the Kilkenny 
Nursery is persuaded that a number of Cape heaths would stand the open air 
in Ireland, without the slightest protection whatever; more especially on the 
sea coast. He has grown in a frame, 6 ft. high behind, and 6 in. high in front, 
without any means of artificial heat whatever, a number of sorts to a high 
degree of perfection. The bed is composed of three layers: the lowest of 
loose stones, 6 in. thick; the one over it of fine, sifted, rotted loam, mixed with 
sand, peat soil being there very scarce; and the third, or surface stratum, of 
sandy peat, 16 in. or 18in. deep. The plants are turned out of the pots into 
this soil; and, during summer, they require frequent watering, all possible air 
on temperate days, and shading on scorching sunny ones, The shading is 
effected by a mat, and the ventilation by tilting up the glass at both ends, so 
as to produce a thorough current of air. In winter, the same attention to air 
is given, but no water whatever. The plants are screened from rain at all 
seasons, and well matted up during severe frosts in winter ; but no kind of ar- 
tificial heat is applied (See Gard. Mag., vol. x. p.206.) Mr. Rutger, during 
his residence in Cornwall, having a number of duplicates of Cape heaths, 
planted a clump of them in the open air, which succeeded admirably with 
very slight protection during winter. ‘ Having made choice of a situation,” 
he says, “ after making a suitable excavation, and laying in the bottom of it 
a thick drainage of brickbats, broken pots, &c., over which I laid dead fern 
roots and other matters, I covered the whole with peat earth to the depth of 
