THE ART OF PROPAGATION. 
63 
like those of nasturtiums and sunflowers, about half an 
inch. It is unwise to bury seeds too deeply. Seeds of 
hardy trees and shrubs should be buried about an inch. 
Half-hardy annuals are best on a hotbed, or in pans or 
shallow boxes in a greenhouse heated to 55 and 65 degs. 
The soil used for pans or boxes should be fairly light and 
sandy, and be sterilised by heating over a fire, or by plac- 
ing a red hot iron or brick in the heap of soil on a potting 
bench before it is placed in the boxes. This precautionary 
measure kills weed seeds, insects, and the spores of fungi, 
especially the “ damping off ” fungus which attacks the 
Fig. 24. WATERSIDE PLANTING. 
Bold groups of Japanese Irises, Royal Ferns, Spiraeas, Day Lilies, etc., 
make a pretty fringe to the margin of a pool. 
stems of young seedlings, and causes them to droop and 
wither. The essential conditions for successful germina- 
tion are moisture, a certain amount of heat, and darkness. 
In the case of hardy kinds sown outdoors, a good water- 
ing should be given after sowing if the weather be dry, 
and the seed bed be protected from sun by covering it 
with branches of evergreens or garden mats till the seeds 
sprout, then gradually expose to the light. Those sown 
on a hotbed should also be shaded with mats till the seed- 
lings show through the soil, after which shade only from 
hot sun. When to be sown in pans or boxes, before sow- 
ing, hold the latter in tepid water till the soil is moist, then 
