Yesterday was gray and cold, but a jolly Christmas was well on its way at LaSalle's greenhouses in Whately. This is only a sample of the plants that are ready to adorn the altars of local churches. I love the creamy color of the 'white' poinsettias. I saw a couple of trays of tiny variegated poinsettias. Of course, LaSalle sells many other plants: the white azalea, white hydrangeas, orchids, Norfolk pines,  amaryllis, and prostrate rosemary to begin the…