Moss saxifrage (bot. Saxifraga x arendsii) is not strictly speaking a species; instead, various hybrids are collected under this name. The low-growing, cushion-forming perennial fits perfectly in sunny rock gardens or as greenery on natural stone walls. The plant has a wide variety of varieties and is also easy to care for.
What is moss saxifrage and where does it grow?
Moss saxifrage (Saxifraga x arendsii) is a cushion-forming, evergreen perennial that thrives in sunny rock gardens and wall crevices. With a height of 10-20 cm, moss saxifrage shows decorative small flowers mostly in spring. There are many different varieties with different flower colors and flowering times.
Origin and distribution
The different forms of the hybrid moss saxifrage (bot. Saxifraga x arendsii) do not always have the same parent species, so a specific classification cannot be made. Strictly speaking, it is not a species term, but rather a collective term for different varieties of the garden saxifrage. Gardeners divide the numerous cultivars into sections to make it easier to differentiate, with species such as the branch moss saxifrage (bot. Saxifraga hypnoides) and the lawn saxifrage (bot. Saxifraga rosacea) probably representing the parent species of most cultivars.
The botanical name Saxifraga x arendsii is an homage to the famous German gardener and plant breeder Georg Arends, in whose nursery the first hybrid saxifrage breeds were created.
Usage
Moss saxifrage is part of classic rock garden planting and should practically not be missing in any stone bed. The undemanding perennial is also very suitable for adding greenery to bare dry stone walls. Although the plant thrives best in bright locations, it is considered to tolerate shade well and can therefore also be planted in semi-shaded to shady beds as a foreground or border. The herbaceous plant looks very pretty as an underplant for deciduous trees and cleverly conceals bare spots. Saxifraga x arendsii are also very suitable as grave plants. Moss saxifrage works particularly well with various ferns and shade grasses, but also with perennials such as bleeding heart (Lamprocapnos spectabilis), fairy flowers (Epimedium), cranesbill (Geranium), common grass (Armeria), purple bells (Heuchera), bergenia (Bergenia), Combine columbine (Aquilegia) or divine flowers (Dodecatheon).
Appearance and growth
The moss saxifrage, which grows up to 15 or 20 centimeters high depending on the variety, forms evergreen leaf rosettes that can develop into dense cushions over time through side shoots and runners.
leaves
The leaf rosettes consist of up to five centimeters long, rather thick leaves that have a dull pale green color and are pinnately cut.
Flowers and flowering time
In spring, significantly taller flower shoots grow from the flat leaf rosettes, with many small, cup-shaped flowers on them. Depending on the variety, these can appear in a wide variety of colors. For example, there are white, yellow, violet, pink or deep red varieties. However, varieties with changing flower colors that can fade or darken over time are particularly interesting.
The main flowering period of the Saxifraga x arendsii hybrids falls in the months of May to June, although some varieties can bloom significantly earlier if the weather permits. After flowering, capsule fruits are formed.
Location and soil
The different Saxifraga arendsii hybrids have very different location requirements. Basically, almost all varieties thrive in partial shade to shade, although some varieties require more light than others. Basically, you can't go wrong with a bright but sunny location. The soil is much more important anyway, as it must have high permeability and be fresh rather than dry. The perennial feels most comfortable in humus-rich, nutrient-rich soil, which is particularly preferable because moss saxifrage is difficult to fertilize due to its often low height. However, the plant also thrives on poor soils, but then relies on a regular supply of nutrients.
Planting moss saxifrage correctly
Plant the moss saxifrage plants in the bed in the months between spring and autumn at intervals of 20 to 30 centimeters, although the recommended planting distance depends heavily on the variety chosen. Therefore, you should definitely follow the instructions on the plant label. Before planting, work mature compost or well-rotted manure into the soil and dip the root ball in a bucket of water before planting. This allows the roots to soak up moisture again and then grow more easily.
Incidentally, specimens planted in spring do not bloom until the following year, which is why autumn planting is preferred for rapid flowering. The cushion-like growth also only begins a few months later.
Watering moss saxifrage
Most Saxifraga arendsii hybrids prefer fresh soil, which is why you should water regularly, especially during longer dry periods. Always water the plants from below, never over the leaves. Water can accumulate in the rosettes, which in turn leads to rot and fungal diseases. For the same reason, a permanently damp surface or even waterlogging must be avoided at all costs. During planting, it makes sense to mulch the area with bark mulch (€13.00 on Amazon), gravel or similar so that the soil does not dry out too quickly and you have to water less.
If the moss saxifrage leaves its leaves hanging, it usually needs water. He althy plants recover quickly after watering and do not suffer any damage.
Fertilize moss saxifrage properly
Basically, you only need to fertilize Saxifraga arendsii hybrids in very poor locations or when there are signs of deficiency. To do this, distribute some compost among the plants and work it lightly - and carefully so as not to damage the roots - into the soil.
Cutting moss saxifrage correctly
Regular pruning is not necessary, but dead leaf rosettes and faded stems should be removed promptly.
Propagate moss saxifrage
The various hybrids of the moss saxifrage can be easily propagated either by division or by rooting cuttings. Since Saxifraga x arendsii only very rarely produces fruits and therefore seeds, propagation via seeds is in principle possible, but is rarely used.
Division
In any case, the plants should be dug up, divided and planted separately in a new location at intervals of two to three years - moss saxifrage has the habit of developing loose growth over time and thus holes in the cushion to get. Regular division ensures compact and dense growth. And this is how it works:
- Dig up the plants carefully.
- Gently shake off any stuck soil.
- Carefully tear or cut the plants apart including the root balls.
- Cut away diseased plant parts and bare areas.
- Place the individual plants in a new location or in fresh substrate.
- Water the planting heavily to promote new root formation.
Cuttings
When propagating cuttings, take young shoots from the edges of the cushion in early summer and plant them either straight into the bed or first into a pot with potting soil. Some of these cuttings are already rooted, as moss saxifrage reproduces itself via runners. By the way, with the help of cuttings you can easily cover up bare spots by planting the plants in exactly those areas. The cuttings grow well within a few weeks and close the cushion gaps.
Wintering
Moss saxifrage is very hardy and only needs light winter protection if it is freshly planted young plants or specimens cultivated in pots. In addition, cold frost - i.e. low temperatures without a protective snow cover - can also become a problem, which is why you should cover the plants with brushwood or leaves in the cases mentioned. Remove the cover in good time in spring so that the perennials can sprout again. However, pay attention to late frosts and protect the plants from them if necessary.
Tip
Moss saxifrage is very robust and is rarely attacked by diseases or pests. Only rosette rot, caused by excessive moisture, can become a problem. In this case, you should cut out diseased parts of the plant and ensure more dryness.
Species and varieties
There are around 480 different species of saxifrage, some of which are difficult to distinguish from one another. The moss saxifrage (bot. Saxifraga x arendsii), which only grows about ten to 20 centimeters high, is ideal for planting in rock gardens, but can also be planted in cracks in walls or on dry stone walls. Here the low perennial shows its decorative flowers, depending on the species and variety, in spring between March and April or in late summer between August and October. There is a large selection of varieties in different flower colors. For example, these are very suitable for ornamental and front gardens:
- 'Carpet of flowers': growth height up to 20 centimeters, carmine pink flowers between March and April
- 'Bob Hawkens': growth height up to 15 centimeters, pink flowers between May and June
- 'Sleeping Beauty': growth height up to 15 centimeters, light red flowers between May and June
- 'Spring Snow': growth height up to 25 centimeters, pure white flowers between May and June
- 'Ingeborg': growth height up to 15 centimeters, dark red flowers between May and June
- 'Peter Pan': growth height up to 15 centimeters, crimson flowers between March and April
- 'Purple Coat': growth height up to 15 centimeters, purple flowers between April and May
- 'Rose Dwarf': growth height up to 20 centimeters, purple-pink flowers between April and May
- 'Snow Carpet': growth height up to 40 centimeters, pure white flowers between March and April
- 'White Pixie': growth height up to 20 centimeters, white flowers between April and May
Moss saxifrage Saxifraga bryoides
The species Saxifraga bryoides, which is native to the Pyrenees and other European mountains, is also known as the moss saxifrage. This cushion-forming perennial is very similar to Saxifraga x arendsii, but usually remains smaller with growth heights of up to ten centimeters. This species also only blooms between July and August and therefore significantly later.
Alternatives / Similar Types
Species that are also often planted in gardens are very similar to the moss saxifrage, such as the garden saxifrage (bot. Saxifraga cortusifolia) or the shrub saxifrage (bot. Saxifraga cotyledon). In contrast to the moss saxifrage, the garden saxifrage can also thrive in semi-shady to shady locations, and it only blooms in autumn between September and October. The shrub saxifrage, on the other hand, requires a sunny place, but only blooms between June and July.
