The cushion phlox is a garden beauty whose homeland is in America. The plant thrives splendidly in Central European gardens if the site conditions are right. As an easy-care perennial, upholstered phlox is very popular in beds. It is also often used as a container plant.
What is cushion phlox?
The cushion phlox (Phlox subulata) is a wintergreen perennial that grows between five and 20 centimeters high and develops creeping or ascending shoots. The herbaceous plant is ideal for rock gardens, dry stone walls and borders. It blooms from March to June in different shades.
Origin
The upholstery phlox, which is also called carpet phlox because of its growth habit, has the Latin name Phlox subulata. The species belongs to the genus of phloxes within the family of weeds. Its homeland is in the northeast of the USA, where it grows on sandy soils on forest edges and in fallow areas. In Central Europe, the cushion phlox is a popular ornamental plant in parks and gardens.
Growth
Phlox subulata grows as a herbaceous plant and covers the ground with dense cushions. The individual shoots grow creeping or ascending and form numerous branches. The upholstered phlox reaches heights of between five and 20 centimeters. It develops a fine root network consisting of fine roots. They reach up to 60 centimeters into the substrate. The plants reproduce via underground runners.
Bloom
From March onwards, the plants develop stem-shaped flowers whose petals have grown into a tube in the lower part. The crown lobes are spread out flat and slightly cut at the edge. The flowers are terminal and grow to about 2.5 centimeters in size.
Phox subulata develops pink flowers with a purple center. The numerous cultivated forms shine in a wide variety of color nuances from white to pink and red to blue. Some varieties develop multi-colored flowers with a contrasting colored eye. They attract wild bees and butterflies, which feed on the sweet nectar. The flowering period lasts until June.
leaves
Phlox subulata is a wintergreen plant. Its leaves are very narrow to needle-shaped and have a smooth edge. The surface is softly hairy. The leaves are arranged oppositely on the shoot. They appear green all year round and lie like a carpet over the ground. In winter the foliage is a little looser than during the growth phase in summer.
Usage
The cushion-shaped perennial decorates rocky crevices in rock gardens and joints on the tops of walls. Due to its location requirements, the herbaceous plant is suitable for beautifying dry stone walls. As an ornamental plant for the border of the bed, the upholstery phlox has not only aesthetic but also functional purposes. It visually delimits perennial plantings and flower beds and creates a magnificent picture on terrace slopes. The upholstered phlox creates colorful accents between floor tiles or on steps.
These are suitable planting partners:
- Price speedwell (Veronica prostrata)
- Candytuft (Iberis sempervirens)
- Stonewort (Alyssum)
- Blue cushion (Aubrieta)
- Cushion Bellflower (Campanula)
Phlox subulata can be planted as a dominant perennial in the bed or as an underplant for trees. The varieties are suitable for decorating troughs and flower pots. They decorate house entrances and can be used as grave decorations.
Edible
The fresh flowers of the cushion phlox are a true delicacy. They taste sweet and not only sweeten desserts but also refreshing starters. The petals refine salads or herb butter. They can be used for colorful flower ice cubes or ice cream. Pluck off individual flowers in spring. During the main flowering period the flavor is fully developed. To ensure that your plant continues to look attractive, you should not pick too many flower heads.
Which location is suitable?
The carpet phlox prefers a location with full sunlight. This is where its floral splendor comes into its own. The perennial can be planted in partial shade, although its flowers will be weaker due to the lack of light.read more
What soil does the plant need?
Ideal is fresh soil with a loamy or clayey substrate that has a high proportion of sand or gravel. The cushion phlox likes a moderately nutrient-rich soil with a pH value between 5.7 and 7.5. It finds optimal growth conditions on a soil with a humus top layer.
Requirements of upholstery phlox:
- does not like saline or oxygen-poor soils
- Tolerates temporarily dry substrate and lime
- suitable for urban climates
Propagate upholstery phlox
The cushion phlox reproduces via root runners and often forms large populations in suitable locations. If the carpet of plants spreads uncontrollably, you can divide the crop. The ideal time for this measure is spring, shortly before or while budding can be seen. You can also divide the plant in late autumn when winter is not yet around the corner.
Dig up the root ball and divide it into small pieces. Plant the divided root balls immediately so that the fine roots do not dry out.read more
Sowing
Propagation via seeds is possible. You can pick the fruits of the cushion phlox after they are ripe. Since the seeds only sprout after a cold stimulus, you should sow them outdoors before winter. It is possible to bring it indoors at temperatures between 16 and 18 degrees. These plants are sensitive to frost in the first year and should only be planted outdoors from the second year onwards.
Since Phlox subulata is perennial, the species is primarily propagated by division or cuttings. The cultivation takes place using related Phlox species that grow as annuals. Seed propagation has the disadvantage that the next generation is not always true to the variety. The offspring combine characteristics of two parent plants and can develop other flower colors.
Cuttings
You can take cuttings from cushion phlox between May and July. The shoot tips should be about five centimeters long and have at least three pairs of leaves. Remove the lowest leaves and place the shoot in a planter filled with potting soil or directly outdoors in a shady place. Keep the substrate moderately moist for the next few weeks. As soon as fresh leaves develop on the cuttings, they can be transplanted.
What is the best time to plant?
Early spring is the optimal time to plant cushion phlox in the garden. The perennials then have enough time to grow well until winter. Regular watering after planting promotes root formation.read more
The correct planting distance
Young plants can be assembled in small tuffs. There is space for up to ten plants per square meter. The planting distance should be around 30 centimeters so that the cushion phlox creates a dense carpet with its neighboring plants within a short time. You can also plant the cushion phlox as a solitaire.
Cushion phlox in pot
The upholstered phlox cuts an equally good figure in the pot as it does outdoors. Use a large pot to allow the roots to spread and branch freely. The planter should have a drainage hole so that water does not build up. Drainage made of gravel, expanded clay or clay shards on the bottom of the pot ensures better water drainage.
Balcony
Because of its low growth habit, upholstered phlox is ideal for beautifying balconies. The creeping shoots are particularly effective in flower boxes. They grow over the edge of the container and create an aesthetic curtain of flowers. The varieties feel particularly comfortable on south-facing balconies with direct sunlight. The perennials spend several years here.
Watering upholstered phlox
In the open field, cushion phlox only requires additional watering during long dry periods. On particularly hot days, you should water the plant in the evening, as soon as the ground has cooled down a little.
If your upholstery phlox grows in very dry locations where water drains away quickly, you should mulch the soil. As a result, the moisture from the subsoil evaporates less quickly and after a while a humus-rich layer forms on the root area, which maintains the water balance.
Cut upholstery phlox correctly
A carpet phlox does not require regular pruning as its growth remains compact. You can regularly remove wilted shoots and inflorescences. This means that the buds that have already formed receive more light. Immediately after flowering, shorten half of all shoot tips. In this way, the plants can be stimulated to bloom a second time.
Pruning
After a few years, you should rejuvenate the upholstery phlox so that the plant grows more lushly again. It tolerates a radical pruning to hand height. For early-flowering varieties, this measure is carried out in late autumn or very early spring. Late-flowering Phlox varieties retain their foliage over the winter so that the roots are better protected from the cold. They are trimmed shortly after winter between February and March.read more
Fertilize upholstery phlox properly
The nutrient requirements of these perennials are low. Before the flowering period begins, you can add some compost. This measure is also recommended as preparation for winter. A layer of mulch protects the soil from freezing and ensures that the wintergreen plants receive sufficient moisture even during the frosty months.
If your plant shows symptoms of a nutrient deficiency, you should mix some nettle manure into the irrigation water or rake a handful of horn meal into the soil. If the plant is under-supplied, it will let flowers and leaves hang.
hardy
Phlox subulata can tolerate temperatures down to -18 degrees Celsius. The plants survive the winter in Central Europe without any problems. They should be watered on frost-free days because their metabolism does not slow down even during the cold months. If there is strong sunlight, you should cover the leaves with a layer of brushwood. The material protects against excessive evaporation and prevents the shoots from drying out.
How do I transplant correctly?
The cushion phlox can be transplanted throughout the entire growth phase. It will regenerate more quickly in its new location if you transplant it shortly before flowering. With this measure you can divide the root ball and rejuvenate the plant in this way.
Pests
The cushion phlox is attacked by various pests that feed on leaf mass and plant sap. If the infestation remains undetected for the time being, the pests can weaken your plant to a great extent.
roundworms
The upholstery phlox is rarely attacked by small stems. The tiny nematodes damage the plant, causing its shoots and leaves to wither over time. In order to combat the pests, pruning close to the ground is necessary. The plants then need some time until they have regenerated.
Since the nematodes overwinter in the substrate, sustainable control is difficult. As a preventive measure, you should transplant the infected upholstery phlox to a new location and completely shake off the old substrate from the roots. Marigolds decimate the pests. They secrete substances that are toxic to the nematodes.
Caterpillars
Occasionally the perennials are attacked by caterpillars that feed on the leaf mass. They leave mealy secretions on the leaves, flowers and fruits. Collect the caterpillars regularly. Insecticides should be used with caution as they not only kill pests but also beneficial insects.
Fungal infestation
Under incorrect care conditions, upholstery phlox can be attacked by various fungi. Be careful not to water the plants from above. Fungal spores find optimal growth conditions in the dense stands. Treating the plant with a fungicide helps against severe fungal infestation.
Powdery mildew
If you discover a white, mealy coating on the leaves, an infestation by powdery mildew may be a possibility. The fungal spores spread when the weather is nice. They require dry conditions. Infected plant parts should be removed generously so that the fungus does not spread further. Improved ventilation helps preventatively (€29.00 at Amazon).
Downy mildew
This fungus causes a whitish or gray coating on the underside of the leaves. Its spores spread in cool and moist conditions. Remove the affected areas and dispose of them with household waste. Make sure that air can circulate between the shoots.
Tip
Create an exciting arrangement with different varieties that creates a firework of colors between spring and summer with constantly new flowers. Tall-growing phlox varieties and small forest phlox varieties not only beautify the garden, but also decorate romantic bouquets as cut flowers.
Cushion phlox is not blooming
If your upholstery phlox is not blooming, you should check it for pest infestation. Pests on leaves or roots weaken the plant, reducing its blooms. Dig up the plant and remove any damaged roots. To prevent nematode infestation, you should completely shake off the substrate from the root ball and place the plant in fresh substrate. Then water the plant so that the soil becomes compacted.
If the root ball sits too deep in the soil, the plant also reacts in some cases by failing to flower. In this case, you should dig up the root ball generously and place it higher so that its surface is flush with the upper layer of soil.
Varieties
- Temiskaming: Blooms between April and May, flowers purple-red. Grows ten to 15 centimeters high.
- Bavaria Blue: Flowering period from April to May with white, pink or pink flowers, blue-violet eye. Growth height between ten and 15 centimeters.
- Dwarf Carpet: Flowering period between April and June, flowers are dark pink, flower center is red. Grows ten to 20 centimeters high.
- Candy Stripes: petals white with pink stripes, flower eye reddish. Grows between five and ten centimeters high.
- Emerald Cushion Blue: Strong-growing, robust. Flowers light purple, between April and June. Growth height five to ten centimeters.
