It is well known that the use of flowers in symbolism is widespread and that it is to be found in most traditions. It is also a very complex symbolism, and our intention here can only be to point out some of the more general meanings. It is obvious, in fact, that the sense of a floral symbol may vary, at least in its secondary modalities, according to the particular flower taken as symbol. and also, as is generally the case in symbolism, that each flower can itself have a plurality of meanings, which may be bound up with each other by certain correspondences.
One of the chief meanings of floral symbolism is that which relates to the feminine or passive principle of manifestation, Prakriti or universal substance. In this respect, the flower is equivalent to a number of other symbols, among which the most important is the cup. Like the cup, the flower by its very form evokes the notion of 'receptacle' , which Prakriti is as regards the influences emanating from Purusha, and one commonly speaks of the calyx [i.e., cup or chalice] of a flower. On the other hand, the blossoming of this same flower simultaneously represents the development of manifestation itself, considered as a production of Prakriti. This double sense is particularly clear in a case such as that of the lotus which, in the East, is the symbolic flower of flowers and which has the special characteristic of blooming on the surface of the water; and as we have explained elsewhere, this surface always represents the domain of a certain state of manifestation, or the plane of reflection of the 'celestial Ray' which expresses the influence of Purusha exercised on this domain in order to realise the possibilities potentially contained therein, enveloped in the primordial indifferentiation of Prakriti.
The above mentioned connection between flower and cup naturally brings to mind the symbolism of the Grail in the Western traditions. We have already seen that among the various objects traditionally associated with the Grail there is a lance which, in the Christian adaptation of the legend, is the lance of the centurion Longinus that made, in the side of Christ, the wound from which flowed the blood and water that Joseph of Arimathea collected in the chalice used at the Last Supper; but it is nonetheless true that this lance or one of its equivalents already existed as a complementary symbol to the chalice or cup in pre-Christian traditions. The lance, in a vertical position, is one form of the 'World Axis' which is identical with the 'celestial Ray' that we just mentioned; and in this connection, it can be recalled also that the solar ray is frequently assimilated to weapons such as the lance or the arrow, though it would be out of place to dwell on these weapons here. On the other hand, in certain representations, the drops of blood fall from the lance itself into the cup; now these drops of blood, in their principial significance, are an image of the influences emanating from Purusha, which evokes the Vedic symbol of the sacrifice of Purusha at the origin of manifestation.
From: Symbols of Sacred Science