The cushion phlox (Phlox subulata) is a famous ground cover in the rock garden. The fact that it is one of the most popular upholstery perennials is not only due to its fantastically beautiful, blue-violet carpet of flowers. In addition, cushion phlox is also incredibly easy to care for.
Originally native to the northern USA, the cushion phlox is characterized by its particularly early flowering period. This occurs as early as April and usually lasts until June. The ground cover is therefore also counted among the so-called spring phloxes within the genus.
By the way: Phlox species are not only characterized by their high ornamental value. In addition, the fire flowers also exude a pleasant fragrance. It turns the flowering perennials into excellent pastures for beneficial insects. Because insects, such as bees or bumblebees, are magically attracted to the beguiling scent of the plants. The sweet-tasting wheel flowers are also edible and can be used, for example, to garnish salads.
Phlox in the garden
Pholsterphlox belongs to the Phlox genus. Most species of this genus are known for their growth of up to 120 cm. Because of their spherical inflorescences, which are available in many different colors, high-growing phlox species are considered to be magnificent perennials.
The cushion phlox, also known as carpet phlox, is clearly out of character here. Its short growth of just 5 to 15 cm makes the dwarf phlox a classic ground cover. This makes it ideal for planting in bare beds. Not only in the rock garden, but also in the cottage garden, flower garden and on the roof garden.
Phlox is even more common in cottage gardens than in rock garden concepts. The planting of carpet phlox to border borders has a long tradition here. Phlox subulata is also interesting for planting on slopes, stone joints and dry stone walls. Especially on dry stone walls, it forms an extremely decorative, hanging carpet that almost flows down the walls.
As an alternative to wall and bed planting, cushion phlox can also be cultivated in pots. That offerssuitable for beautifying balconies, steps or house entrances, for example. Beautiful planting examples in buckets include hanging baskets or cultures in flower boxes.
» Tip: Planting the cushion phlox in small tuffs of 5 to 10 pieces is a good idea for a spacious carpet of flowers. The plant cushion can then spread all the faster.
Upholstery phlox - location and planting
Phlox actually tolerates all light conditions from sunny to partially shaded locations. It is also relatively hardy with a cold resistance down to -18 °C and needs at most a light winter protection.
With regard to the soil, cushion phlox wants a lime-free and low-humus substrate with a slightly acidic to neutral pH value of 5.7 to 7.5 points. The soil should be sandy-loamy to gritty-loamy. The nutrient requirement of Phlox subulata is comparatively low. With these site conditions, good planting partners are other ground covers such as
- Blue Pillow
- Candytufts
- Alyssum
- or Cushion Bellflower
Plant cushion phlox
1. Step:
Planting cushion phlox outdoors is best done in early spring. You can also plant pot cultures well into the summer.
2. Step:
Deeply loosen the site soil. If necessary, it can be re-optimized with sand or gravel. Drainage is also recommended, because Phlox subulata prefers dry to freshly moist substrates. Planters therefore also need sufficient drainage holes and, if necessary, drainage made of gravel or expanded clay.
3. Step:
The correct planting distance for cushion phlox is based on its final growth width of up to 30 cm. In addition, the planting depth should be at least 20 cm. This ensures that the location is established quickly. For this purpose, new plantings must also be watered well in the first few weeks.
Watering and fertilizing upholstery phlox
After the first watering, you can largely stop watering. The ground cover can even withstand short periods of drought without any problems. Additional watering is only advisable on very hot summer days. It is best to water here in the evening hours or early in the morning. This prevents burns on the plant - caused by too wet leaves in the blazing midday sun.
Since the nutrient requirement of cushion phlox is not particularly high, moderate fertilization during the flowering period is sufficient. Enter just a handful herecompost or horn meal. Alternatively, nettle manure can be used for fertilization. An additional layer of mulch protects Phlox subulata from ground frost in winter and keeps weeds away.
Pruning and propagating cushion phlox
Thanks to its compact growth, cushion phlox grows extremely shapely even without pruning. Any wilted parts of the plant are removed regularly. A second flowering can be stimulated by halving faded shoots after the regular flowering period.
Older plants still benefit from a radical pruning from time to time. It rejuvenates the perennial and ensures that it grows stronger again later. This guarantees compact carpets of plants even after several years of standing. Therefore, cut back aging perennials by about two thirds after flowering.
➔ Multiply cushion phlox by root division
The easiest way to propagate cushion phlox is by root division. To do this, the plant is dug up in spring and carefully divided into two equal halves with a sharp knife.
➔ Multiply upholstery phlox by cuttings
Phlox subulata cuttings can be taken in summer. Choose only strong and well-developed shoots and cut them off at a length of about 5 cm. Remove the lower pairs of leaves to allow the shoot to root quickly in that area.
The cuttings are then placed in a substrate with potting soil. Kept in a shady spot and watered moderately but regularly, shoots should be rooted in just a few weeks.
➔ Multiply cushion phlox by seed
Propagating cushion phlox by sowing is a little more tedious. The plant develops the seeds required for this after flowering in the form of small capsule fruits. The seeds of the cushion phlox are frost germs and need a cold stimulus to germinate outdoors. They must therefore be sown in winter. For pre-breeding indoors, on the other hand, temperatures of 16 to 18 °C are sufficient.
» Important: Phlox cultures propagated by sowing indoors are still very sensitive to frost in the first year. They should therefore only be planted out in the following year.
Overwintering cushion phlox correctly
Plantings outdoors of Phlox subulata are actually very frost hardy. If you cover the plants with some mulch or brushwood in autumn, you have made good provisions. Watering is done very sparingly on frost-free days in winter.
For pot cultures could do somethingextensive winter protection measures may be necessary. Depending on where the cushion phlox is located, you may need to insulate the walls and bottom of the planter. Coconut mats or garden fleece are ideal for this. If you also place the pot on wooden blocks, you can ward off ground frost from below.
Upholstery phlox - 3 interesting varieties
While the ancestor of the Phlox subulata is famous for its dense, blue-purple flower pile, there are now numerous varieties with different flower colours. Pink and white flowers in particular are common in the cushion phlox varieties. Three very popular varieties are:
Carpet Flame Flower 'Scarlet Flame'
| Carpet phlox 'Scarlet Flame' (Phlox subulata 'Scarlet Flame') | |
|---|---|
| Flower color: | bright red |
| Growth: | 5 - 10 cm |
| Growth: | 25 - 30 cm |
| Flowering: | April to May |
| Location: | Sun |
| Floor: | dry to fresh, well-drained, nutritious |
Carpet Phlox 'Amazing Grace'
| Carpet phlox 'Amazing Grace' (Phlox subulata 'Amazing Grace') | |
|---|---|
| Flower color: | white |
| Growth: | 5 - 10 cm |
| Growth: | 25 - 30 cm |
| Flowering: | April to May |
| Location: | Sun |
| Floor: | permeable, sandy, nutritious |
Carpet phlox 'Candy Stripes'
| Carpet phlox 'Candy Stripes' (Phlox subulata 'Candy Stripes') | |
|---|---|
| Flower color: | pink, white striped |
| Growth: | 5 - 10 cm |
| Growth: | cushion-like, flat creeping |
| Flowering: | April to May |
| Location: | Sun |
| Floor: | slightly dry to fresh, well-drained, sandy, nutritious |
Cushion phlox 'Candy Stripes' - white flowers with delicate pink stripes
Cushion phlox 'White Delight' - white flowers
Cushion phlox 'Dwarf Carpet' - pink flowers
Diseases and Pests
Unfortunately, the sweet scent of the cushion phlox doesn't just attract beneficial insects. A number of pests haunt the ground cover with similar frequency. There are also a few fungal diseases thatOccasionally troubling flowering shrubs.
➔ Pest Caterpillars
The low-growing cushion phlox is particularly popular with crawling caterpillars and worms. They get to the leaves close to the ground very easily and eat them eagerly. A caterpillar infestation can usually be recognized by the excretion products of the pests. It appears as a mealy coating on the leaves, but also on the inflorescences and fruit heads.
Common insecticides are not always effective against caterpillars. In addition, the chemical club often not only kills the pests but also beneficial insects. It is therefore better to collect the caterpillars from the beneficial pastures.
➔ Nematodes
Fireworms are often used to deal with a caterpillar infestation. However, threadworms such as nematodes on cushion phlox are another common pest infestation. They deprive the plant of important nutrients in the long term, so that shoots and leaves are increasingly noticeable due to stunted growth.
If the pole phlox is infested with nematodes, a radical pruning is first of all necessary. However, the roundworms then continue to live in the site substrate and also overwinter there. A soil replacement is therefore indispensable. The old soil should be shaken off the plant roots very carefully. Ideally, you should also wash the roots thoroughly under running water.
» Tip: Group planting with marigolds (marigolds) may prevent nematode infestation. On the one hand, the strong smell of the flowers is very unattractive to the pests. On the other hand, marigolds are known to secrete toxic substances that reliably keep nematodes away.
➔ Mildew
Both powdery mildew and downy mildew are among the most common fungal diseases on cushion phlox. Powdery mildew can be recognized by the whitish powdery coating on the upper side of the leaf. In the case of downy mildew, a white-grey fungal coating is found on the underside of the leaf.
Whereas powdery mildew prefers to spread in dry site conditions, downy mildew prefers damp conditions. It is therefore very important for cushion phlox to ensure balanced soil moisture without waterlogging and extreme dryness. In addition, good air circulation should be guaranteed. A sufficiently permeable site substrate, as well as observing the specified planting distance, are the best options for prevention.
» Important: Infected parts of the plant must be removed under all circumstances if a fungal disease is present. Just like thatprevent further spread of the fungal spores. Please do not dispose of the parts of the plant in the compost, but isolate them in the household waste. Otherwise, the spores will seep into the compost soil and infect any plants that are later fertilized with it.