Annuals and Biennials 
hardened off by gradual inuring to the open air, 
and are finally planted in their places at the end 
of May or beginning of June. Autumn-sown 
annuals are in fact treated as biennials, except 
that in the case of true biennials these are sown 
earlier in the year — from the beginning of July 
to the middle of August. Annuals when sown 
in autumn are much more vigorous than when 
sown in spring. 
Biennials are plants that must be grown one 
year to flower the next ; of these some of the 
best known examples are Wallflowers, Sweet 
Williams, and Canterbury Bells. There are also 
a number of plants from tropical and sub- 
tropical regions that are actually perennial but 
are not hardy in our climate ; these it is con- 
venient to grow as biennials, giving winter 
protection and planting out at the end of May 
or beginning of J une. Any divergence from the 
above general rules of culture, treatment, or 
time of sowing will be found mentioned in the 
note relating to the plant. 
XIV 
