The annual Phlox, also called Phlox drummondii, is an annual herbaceous plant, native to central-northern America; produces low bushes, consisting of numerous branched stems, 35-45 cm tall; the leaves are lanceolate, thin, light green, covered with a fine down. In spring it produces numerous small trumpet flowers, delicately scented, gathered in umbrella-shaped inflorescences. The flowers are bright pink, but there are very many hybrids, with light pink, red flowers, and also with contrasting color zones; 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 encourage the development of 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 faded flowers favors the production of new buds.
The annual flox redirects 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 a fairly mild winter climate, to plant the seedlings already in autumn, so as to obtain an abundant flowering already towards the end of winter. These plants in fact 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 phloxes in autumn, at the end of winter and in late summer.
Phlox drummondii, in the wild, easily tolerates drought, but water shortage interrupts flowering; we therefore advise, during the vegetative period, to water regularly, avoiding to leave the soil dry for excessively long periods of time.
Annual flox are grown in the common garden soil, lightened with universal soil and enriched with organic fertilizer; to obtain an excellent drainage, remember to add a good quantity of river sand to the substrate. They are also cultivated in pots, remembering to water the substratum regularly. The ideal soil for their growth is soft, fertile and well-drained.
Annual phlox reproduction occurs by seed, in autumn, in spring or in late summer; often the plants of Phlox drummondii are self-seeding, in this way every year we get new plants always in the same area of the garden. The seeds of the plant must however be placed in a container with sand or soil and covered with a cloth to protect them from the cold. Once the seeds begin to sprout, you can remove the cloth and expose them carefully in the sunlight. It is good to let the seedlings grow until they reach the strength necessary to be poured and planted in individual pots or in the garden.
Annual phlox - Phlox drummondii: Pests and diseases
Phlox drummondii is occasionally attacked by aphids although it is a species quite resistant to pest attack and disease development. If the aphids appear on the stem and leaves of the plant, the entire plant must be washed with a sponge, manually eliminating the aphids. Another remedy is to use specific pesticide products that can be purchased in the best garden centers and nurseries. A further problem could be the development of fungal diseases due to humidity. The problem can be solved by administering fungicides to the plant.