The annual phlox, also called Phlox drummondii is an annual herbaceous plant, native to central-northern America; it produces low bushes, made up of numerous branched stems, 35-45 cm high; the leaves are lanceolate, thin, light green, covered with a thin hair. In spring it produces numerous small trumpet flowers, delicately scented, gathered in umbrella inflorescences. The flowers are bright pink, but there are many hybrids, with light pink, red flowers, and also with contrasting color areas; they are also used as cut flowers. This plant is very suitable to be placed in spots in flower beds, or even for low borders in annual flower beds. To favor the development of the shrubs it is advisable to trim the young plants as soon as they reach 10-15 cm in height, so as to promote the development of multiple branches; we also remember that the removal of the withered flowers favors the production of new buds.
The annual phlox draws up sunny positions; in principle it does not fear the cold, but every small plant has a fairly short life. The resistance to short frosts allows, in areas with fairly mild winter weather, to plant the seedlings already in autumn, so as to obtain abundant flowering already towards the end of winter. In fact, these plants bloom continuously until the temperatures rise above 30 ° C, or until they drop below 12-15 ° C: it is therefore possible to sow the annual phlox in autumn, at the end of winter and in late summer.