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Annual Phlox is a common ornamental annual flower that blooms during the summer. It can grow in different shapes and forms but always has two beautiful long petals, four sepals, and no stamens or pistils. This plant is easy to grow and doesn't require much maintenance if you follow the correct steps.
Description
Phlox are perennial herbs with alternate leaves with entire margins; flowers are in dense terminal clusters (racemes) at the end of the branches from which the leaves arise. The flowers comprise five petals, primarily white with darker purple spots inside and a yellow tip. The calyx has five sepals joined at their base into a tube for one or two stamens, each with an anther that reaches beyond their throats. The ovary has three styles surrounding one or two stigma lobes atop a style through which pollen may be released as it travels up into another flower cluster.
Related Species
Phlox is a genus of 30 herbaceous flowering plants in the subfamily Phloxineae, tribe Gilliesieae. The genus is native to temperate and Arctic regions. In addition to the common name "phloxes'' or "floxes," they have other common names, including blue flax, blue flax lily, blue flax lily-of-the-valley, western wild clover, western wild root, mason's crown, mason's knotweed, mason's wort, lizard's tail, and lizard's tail cockscomb.
Growing From Seed
The following is a step-by-step guide to growing annual Phlox from seed:
- Plant the seeds in late spring, summer, or early fall. Plant seeds at least 2 inches deep, with some distance between each seed. The ideal depth for planting depends on the variety of annual Phlox and the weather conditions in your area. You can also plant seeds directly into the soil, but germinating may take longer. If you choose this method, allow about two weeks for the seedlings to emerge before transplanting them into pots or garden beds.
- Water regularly until the plants have well-established roots (at least a week). Use lukewarm water no more than lukewarm so that they don't get too wet and rot away before they begin to sprout leaves and flowers.
- Fertilize your annual Phlox with composted chicken manure or blood meal once every three weeks until flowering begins (about ten days after germination).
Hardiness Zones
Annual Phlox and Tall Annual Phlox is only hardy in USDA Zones 3-11. It can tolerate temperatures down to -40 degrees F but performs better in dry weather and should be protected from winter winds.
Maturity Size
The maturity size of the Annual Phlox is small (1 1/4 to 2 inches in diameter) and is borne on a scape that is 6 to 12 inches tall. The plant blooms from midsummer through fall with white flowers tinted purple or pink at their base.
Potting
The potting mixture should be well-drained, with sand added to help aerate the soil. Plant the Annual Phlox in the center of the hole, ensuring that the roots are not disturbed and spread out evenly. Use a soil mix with plenty of organic matter like compost or peat moss. You can also use a commercial mix if you want to save some time. After planting your Annual Phlox, water it thoroughly so that the plant has enough moisture to grow well.
Light Requirements
Annual Phlox needs light to germinate and grow. It can be grown in partial shade to full sun. You must give it enough light to ensure your annual Phlox has a good chance of blooming. The plant will do fine if you live where the sun shines through your windows. However, if you get too much direct sunlight, it could burn the leaves and flowers.
Water Requirements
Phlox is a plant that likes to be in moist soil but not too wet. It needs at least six inches of water per week but can tolerate even less. You should water your annual Phlox once a week if you live in hot areas and dry out quickly during the summer. Some gardeners prefer to keep their annual Phlox in pots on the porch for easy care.
Some people think Annual Phlox doesn't like being overwatered because it tends to drop its flowers when wet for too long, but this is not true. Giving your annual Phlox a little extra water now and then will reward you with beautiful flowers all season long.
Soil Requirements
The Annual Phlox is a tender perennial that prefers moist, acid soils at least 6 inches deep. This plant does not tolerate wet or poorly drained soil. The plant can be grown in clay or sandy loam soil with a pH range of 5.5 to 7.0; it will perform best in well-drained soil with a neutral pH.
Annual Phlox can tolerate light foot traffic, but it's not recommended for areas where heavy traffic is expected. If you have an outdoor container garden, you can plant this flower near the base of your plants for the best results.
Fertilizing
Annual Phlox only requires a little attention, but it does need an occasional fertilizer application when the plants are young. The best time to apply fertilizer is just before the plants flower their first year or after you have cut them back if you wish to encourage more blooms.
Some annuals require light nitrogen for growth, while others will do fine on dark or no nitrogen. Some plants grow well even if fertilized too heavily, while others will rot if they receive too much nitrogen.
Pests and Disease Problems
The following pests and diseases can attack the annual Phlox in the garden:
Thrips - these are tiny insects that feed on the leaves and flowers. They can cause damage by making holes in the leaves or by causing damage to the flower buds. To prevent this from happening, treat the plant with insecticidal soap spray twice a week for three weeks after planting. This will help to get rid of them.
Aphids - these are small, soft-bodied insects that suck sap from plants. They can be very troublesome on annual phlox plants if they can build up in large numbers. To prevent this, treat your annual phlox plants with insecticidal soap spray every week for three weeks after planting. This should kill any existing aphids on your plants, so they don't have time to reproduce and multiply into an infestation problem later.
The annual Phlox is susceptible to several bacterial, viral, and fungal infections. The most severe diseases are bacterial leaf spots and brown patches. Bacterial leaf spots are caused by the bacterium Erysiphe Cichoracearum, which causes spots on the leaves. Control leaf spots with insecticidal soap or lime sulfur sprays. A brown patch is characterized by brown lesions on the leaf's upper surface. Severely affected plants may die within two weeks. Control brown patches with lime sulfur sprays or insecticidal oils applied to foliage at every irrigation cycle.
Pruning
Pruning annual Phlox is essential to maintain the shape and size of the plant. To prune, cut the stem back to about 12 inches above the soil line, removing all branches at that height. If you have several plants, remove one or two branches of each and remove them altogether. Pruning annual Phlox is to remove old wood with no leaves, flowers, or roots. This can be done in late winter or early spring after flowering.
Annual Phlox is an easy-to-grow, herbaceous Perennial that produces an abundance of double purple flowers. The blooms are long-lasting and display unique colors.
