Flowers: Species dependent: Late spring through to autumn.
Flower Details: White, red, pink. Small. Five petals. Large genus, so much variation e.g., Saxifraga stolonifera has pointed petals, whilst Saxifraga rivularis has a more rounded petal.
Foliage: Succulent. Hairy. Rosettes (at end of runners). Oblong to ovate. Creeping.
Sowing: Cover seed. Germination time: two weeks to two months. Spacing 4 to 18 inches (10—45 cm). Method 1: Seeds should first be sown into flats in the autumn. Next sink the flat into the ground in an area that offers shade, preferably close to a wall that faces north. Provide a glass/plastic covering. Keep an eye on the flats to ensure that the soil remains moist. Bring the flats indoor at the beginning of spring and keep at ~70°F (21°C). Transplant seedlings outdoors following the last frost. Method 2: In the spring, sow seeds in a moist growing medium in flats, wrap in a large plastic bag, then stratify by refrigeration for three weeks. Next bury the flat as described above. Once seedlings emerge transplant them to their final location.
Requirements and care: Partial or full shade, will not tolerate midday sun. Good drainage, especially in the winter. Moist, sandy/gritty soil. Keep soil cool. Add lime. Regular watering during the summer to maintain moist soil. Propagate: from root runners.
Closely Related Species:Astilbe, Heuchera, and Micranthes.
Miscellaneous: The scientific name describes the plant’s medicinal ability to break kidney stones – Saxum (rock) and frangere (to break). Flowers of many species are edible, e.g., Saxifraga oppositifolia has semi-sweet petals.
How to Grow Saxifrage and other Saxifraga
When growing Saxifraga plant species from seed it is probably easiest to sow outdoors in flats in the spring. First the seeds should be sown into flats (lightly cover the seeds) then imbibed by placing the flats in a black bag, then placing in the fridge for three weeks. The flats should then be sank into a shady part of the garden and covered with glass.
Germination should take from a couple of weeks to a couple of months. Transplant the seedlings into their final location as they appear; this should be a fully or partially shaded part of the garden that has good drainage.
Ideally the soil that they grow in should be gritty or sandy, and both moist and cool. The plants should be spaced at 10 cm (small), 25 cm (medium) or 40 cm (large Saxifraga varieties) apart.
Caring for Saxifraga
It is easy to look after Saxifrage and related plants; they like a moist soil so keep well watered in dry periods. If you require more plants then use the root runners that they produce for propagation.