This chapter focuses on herbaceous perennials, annuals, and bulbs. Each of these three groups will be presented separately. Most plants in these groups are prized for their showy blossoms. All three groups have been extensively hybridized by commercial growers to change the following characteristics:
flower color and size
foliage color, size, and texture
hardiness
ability to self-clean (drop spent blooms)
bloom time
petal number (increase)
fragrance
disease resistance
drought tolerance
shade and sun tolerance
to continue.