Saxifraga

( sak - SIFF - rag - uh )

At-A-Glance Information

Commonly called Saxifrage or Rockfoil, this genus includes flowering perennial plants which typically need regular water to perform well in the landscape. They prefer partial shade, and form creeping groundcovers. Species are native to North America and Europe, where they grow in cold, mountainous, alpine regions. Use Saxifrage in rock gardens, stone walls, or alpine and crevice gardens. They grow well in containers, and can also be used as small-space no-traffic groundcover.

saxifraga Species and Varietals

Saxifrage is the type genus member of the plant family Saxifragaceae, and includes 473 species. The plants in this genus are closely related to Heuchera (Alumroot), Tiarella (Foamflower), Rodgersia (Rodger's Flower), and Astilbe (False Spirea). The genus name is Latin for 'stone breaker', referring to the rocky natural habitat of most species. Saxifrage growing zones vary depending on the species cultivated; for more information, see the descriptions below. To find your zone, click here: Zone Map.

Saxifraga aizoides (Yellow Mountain Saxifrage, Yellow Saxifrage)
These evergreen perennial herbaceous plants are native to North America, Greenland, and Europe. It is an endangered species in some areas of its natural range. Individual plants reach about 4 inches tall, and spread by short rhizomes, forming mats of small colonies over time. Flowers are yellow to green. Yellow Mountain Saxifrage is suited for growing in USDA hardiness zones 2-7.

Saxifraga bronchialis (Matted Saxifrage, Spotted Saxifrage, Yellowdot Saxifrage)
Native to northern Asia and North America. Foliage is green to dark green and often has reddish tips and undersides. Floral stems are green to reddish and reach up to 8 inches tall. Blooms are yellow-white and have small red to yellow spots. Stamens are prominent. Matted Saxifrage grows well in UDSA hardiness zones 1 through 6.

Saxifraga cochlearis (Spoon-Leaved Saxifrage, Silver Saxifrage, Encrusted Saxifrage, Saxifrage en Cuillère, Saxifrage Cochléaire, Saxifrage en Coquille, Sassifraga Spatolata)
This species is native to France and Italy and produces red flowering stems that reach about 8 inches tall when in bloom. Basal foliage is light green to grey-green. Cultivars include 'Minor' (with white flowers to 3-4 inches tall) and 'Major' (with large silvery rosettes and branched flowering stems). This species is suited for growing in USDA hardiness zones 5-8.

Saxifraga federici-augusti (Saxifraga grisebachii) (Engleria Saxifrage, Grisebach's Saxifrage, Σαξιφράγα, Little Urchin, Hedgehog Plant, Iriqëza, Federico's Rock-Foil, Federico's Saxifrage, Federikova Kamenjarka)
Reaching up to 6 inches tall when in bloom, these plants are native to Greece, Albania, and former Yugoslavia. Flowers are reddish purple, and bloom from January through March in the plant's native range. Basal foliage forms a rosette of green foliage, from which flowering stems emerge. The main cultivar of this species is 'Wisely', with sturdy flower inflorescences and rich crimson-red flower spikes. USDA zones 4-8.

Saxifraga fortunei (Fortune Saxifrage, Fortune's Saxifrage, Japanese Rockfoil, Autumn Saxifrage, Daimonziso, Daimonjisou, 大文字草, Toothed-Petal Saxifrage, Chi Ban Hu Er Cao, 齿瓣虎耳草, Central China Saxifrage, Hua Zhong Hu Er Cao, 华中虎耳草, Rock Rice Cake Grass, Bawitteokpul, 바위떡풀)
Native to China, Japan and Korea, these plants form basal tufts of dull green foliage. Flowering stems are red, and are topped with clusters of long-rayed flowers, creating a delicate blooming look. Leaves are rounded and fleshy, sometimes flushed with red or pink tones in cooler weather. Varietals include 'Angelina Johnson' (to 10 in. with vibrant red stems and white blooms), 'Blackberry and Apple Pie' (with maroon leaf undersides and cream flowers), 'Moe' (to 10 in.; apple-green foliage and pale yellow-white flowers), 'Pink Haze' (to 6-10 in. tall and a foot wide with soft pink blooms), 'Rokujo' (with reddish leaves and airy white blooms to 12 in.), 'Sue Drew' (with dark maroon tinged foliage and pink-white flowers to 10 in.), and 'Sugar Plum Fairy' (also called 'Toujya', with sugar-pink flowers to 16 inches tall). USDA hardiness zones 5-9.

Saxifraga hyperborea (Saxifraga debilis, Saxifraga rivularis) (Pygmy Saxifrage, Weak Saxifrage, Brook Saxifrage, Hyperborean Saxifrage, Камнеломка гиперборейская, Northern Saxifrage, Камнеломка северная, Polar Rockfoil, Polar-stenbræk, Arctic Saxifrage, Saxifrage Hyperboréale)
These plants are native to the western United States, Canada, Alaska, Greenland, and Russia. The species forms small mats of basal foliage to 4 inches tall that are typically green. Leaves are sometimes edged with red. Foliage can appear purple especially during cooler temperatures. Flowers are purple or white. Best in USDA hardiness zones 1-4.

Saxifraga hypnoides (Mossy Saxifrage, Cut-Leaved Saxifrage, Dovedale Moss, Eve's Cushion, Indian Moss, Lady's Cushion, Queen's Cushion, Highland Saxifrage, Saxifrage mousse, Moossteinbrech, Mosesildre)
These plants are native to northwestern Europe, and are small perennials that form mats of green mossy foliage. They are suited for USDA hardiness zones 4-8. Flowering stems are bronze to reddish, and are topped with white flowers that have yellow centers. There are forms with red to pinkish flowers available as garden ornamentals. The two main cultivars of this species are 'Kingii' (compact with red-bronze tinted foliage in cool weather) and 'Whitlavei' (with heavier blooms of larger white flowers).

Saxifraga oppositifolia (Purple Saxifrage, Purple Mountain Saxifrage)
These plants are common in mountainous areas in the Arctic, northern Britain, the Alps and around the Rocky Mountains. Individual plants are low-growers, reaching about 2 inches tall, and produce solitary flowers on short stalks. Blooms are purple to lilac, and bloom throughout the summer months. This is a popular plant for alpine gardens but will struggle in warmer climates, and performs well in USDA zones 1-7. Cultivars include 'Splendens' (with round rose-purple flowers), 'W.A. Clarke' (with crimson flowers), 'Wetterhorn' (with large rosey red flowers), 'Coccinea' (with smaller red blooms), 'Florissa' (with smaller leaves and lilac flowers), 'Latina' (with silver-white foliage and deep pink blooms), 'Skye Form' (with smaller leaves and bright magenta flowers), and 'Alba' (with white flowers).

Saxifraga paniculata (Alpine Saxifrage, Encrusted Saxifrage, Lifelong Saxifrage, Lime-Encrusted Saxifrage, Livelong Saxifrage, White Mountain Saxifrage, Silver Saxifrage)
These plants basal rosettes of fleshy foliage and flower from mid-June through early August in their native range (temperate Northern Hemisphere). They are suited for USDA hardiness zones 3-9. and are commonly cultivated as garden ornamentals. Cultivars include 'Minor' (with tiny silvery rosettes with cream-white blooms), 'Rex' (with larger rosettes and pure cream blooms), 'Rosea' (with pink flowers), and 'Venetia' (with upward-facing green leaves with purple undersides).

Saxifraga rosacea (Saxifraga decipiens) (Mossy Saxifrage, Irish Saxifrage, Rosy Saxifrage, Saxifrage, Rockfoil, Kerry Saxifrage, Crimson Moss, Toppasteinbrjótur, Moos-Steinbrech)
This species grows well in USDA hardiness zones 4-8 or Sunset growing zones 2-7 and 14-17, and is native to Europe. They form low mats of foliage 2-4 inches tall and a foot wide. Leaves are green and glossy and white flowers (sometimes in cream, pink or red). In cool-summer areas, they need partial shade, but in warmer areas, full shade is preferred. Varieties include 'Peter Pan' (with white flowers that open from pink buds), and Saxifraga rosacea sternbergii (with pink-flushed white flowers).

Saxifraga spathularis (St. Patrick's Cabbage, Saint Patrick's Cabbage, Prattling Parnell, Pyrenean Saxifrage, Fox's Cabbage, Cabáiste Mhadra Rua, Couve de São João, Abelairiña, Abrairiña, Abreiriña)
These plants form basal rosettes of toothed leaves and are native to Ireland, Portugal, and Spain. They are suited for growing in USDA hardiness zones 6a-9b. Flowering stems are leafless, rising from foliage to hold up pinkish flowers. At maturity, plants reach up to between 4 and 8 inches tall with 10-inch flowering stems.

Saxifraga stolonifera (Saxifraga sarmentosa) (Strawberry Geranium, Creeping Saxifrage, Roving Sailor, Aaron's Beard, Mother of Thousands, Creeping Rockfoil, Strawberry Begonia, Strawberry Saxifrage, Tiger's Ear Herb, Hǔěrcǎo, 虎耳草, Yukinoshita, 雪の下, ユキノシタ)
This species grows well in USDA hardiness zones zones 2-9 and 14-24 and is native to China and Japan. It forms a rosette to 6-8 inches tall and a foot wide, and will expand rapidly via runners, similar to Strawberry plants. Leaves are round and green, and it blooms in late summer and fall in loose clusters. Flowers are white. Great as a groundcover in areas that do not receive hard freezes. It needs partial or full shade. Variety 'Maroon Beauty' has leaves with maroon markings on them.

Saxifraga umbrosa (True London Pride, None-So-Pretty, King's Feather, Kiss-Me-Quick, Leaf of St. Patrick, Prattling Parnell, Pyrenean Saxifrage, Sailor Plant, St. Anne's Needlework, Whimsey, St. Patrick's Cabbage, Look Up and Kiss Me)
This species grows well in zones 2-7 and 14-17 and is native to the Pyrenees. Leaves are shiny and green, and flowers bloom in springtime. Flowers are pink and stems are wine red. Great groundcover for small shady areas, and they love being near rocks. Variety Saxifraga umbrosa primuloides is a compact, dwarf form. Cultivars of the species include 'Clarence Elliott' (green foliage and pink-speckled blossoms), 'Variegata' (also known as Golden London Pride, with green foliage splashed with yellow), 'Elliott's Variety' (compact with deep pink flowers), and 'Primuloides' (to a few centimeters tall with delicate pink blooms).

Saxifraga x urbium (London Pride, St. Patrick's Cabbage, Whimsey, Prattling Parnell, Look Up and Kiss Me)
This hybrid (S. spathularis x S. umbrosa) grows well in zones 4-9 and reaches a foot tall and 2 feet wide at maturity when in bloom. Flowers are pale pink and open in summertime. This species needs partial to full shade to perform well and is suited for USDA hardiness zones 6-9 or Sunset growing zones 2-9 and 14-17.

Caring for saxifraga

Saxifraga plants should be situated in a spot in the landscape that receives full sun (between 6 and 8 hours each day is ideal). When these flowers are grown in less light, they will not flower as profusely. Rockfoil appreciates a spot that is somewhat sheltered from wind and hot sun (partial shade in the afternoon is best). Ensure that soil is well-draining, light, and has a pH of between 6.0 and 7.5 (slightly acidic to neutral). Saxifraga plants are particularly sensitive to boggy soils and have a tendency to develop issues with root rot when grown in substrate that is kept too moist. If local soils are particularly poor in nutrients or do not drain well, make sure to amend the planting area with plenty of organic compost and sand before installing. Mulch around the base of plants with grit or gravel to prevent waterlogging around the crown of the plant.

Water new plantings regularly as they establish a strong root system in their new home. At maturity, these plants perform well in consistently moist soils. Saxifrage does not need fertilizing. Pruning is simple; remove spent flowering stems when blooms fade to encourage rebloom and discourage re-seeding. Every few years, divide plants to maintain good root health. For instructions on how to divide Saxifrage plants successfully, see the Propagation section below. Saxifrage plants can be expected to survive in the landscape for 3 to 6 years or more before needing to be replaced. In areas where they are grown as annuals, they are typically pulled and composted at the end of the growing season and replaced in the next with new plants.

Caring for Saxifraga in Containers
Saxifraga flowers are wonderful in the ground, but can also be grown in containers. Choose a container that is at least a few inches wider and deeper than the nursery pot or root ball. Ensure that the pot has adequate drainage holes on the bottom to allow for excess water to flow away. Fill with a well-draining potting mix amended with organic material and perlite, and top with a layer of mulch to suppress weed growth, maintain consistent soil temperatures, and to increase soil moisture retention. Water regularly as the plant establishes itself in its new home. Once established, waterings can be lessened. Saxifrage plants grown in containers will need more frequent irrigation than those grown in the ground. As a general rule of thumb, water whenever the top few inches of soil feels dry to the touch. Prune to remove dead, damaged, or diseased foliage at any time during the growing season. Every few years, check the bottom of the pot to ensure that the plant is not outgrowing its root space. If roots are growing through the drainage holes in the bottom of the container, it is a good indication that it needs to be potted up; choose a slightly larger container and repot. Divide at repotting time; for instructions on how to divide Saxifrage plants, see the Propagation section below.

Propagation

Saxifraga, or Saxifrage, can be propagated by division, cutting or seed. To ensure that your propagated plant will have the exact same qualities and characteristics as the parent plant, use the division or cutting method. If you would like to experiment and see what plant you can grow from seed, just keep in mind that it will not necessarily be the same as the parent plant, especially if you are propagating a hybrid cultivar. To propagate your Saxifrage, follow the instructions below:

Propagating Saxifraga by Seed

Keep in mind that the plant you get from seed will not necessarily mimic all of the characteristics of the parent plant. To propagate by seed, you will need a paper bag, a pot or tray filled with well-draining compost or other organic material, a spray bottle and a fork. The best potting medium for seed germination is a light blend of 1/3 pasteurized soil or compost, 1/3 sand, vermiculite or perlite, and 1/3 coconut coir or peat moss.
Harvest your seeds in late spring to fall. They are held in seed capsules which form after flowers fade. They will dry, turn brown, and split open at the top when ripe to release the seeds. Cut the flower heads from the plant and place them in a container or bag, then bring them indoors. The seeds are very small, so it is best to work with them in a space that does not have much air movement.
Four to six weeks before the last frost of the year, get a container prepared. Water the prepared seed tray or pot filled with soil and ensure that good drainage is occurring. Place your seeds in your prepared pot or seed tray about a quarter inch to a half-inch under the soil surface. Cover them with soil and water with your spray bottle. Place your tray of seeds in a warm area that receives bright, indirect light. A greenhouse is the most ideal climate, but a planting tray inside a window will do as well. Germination usually takes 2-6 weeks from sowing.
Keep the seedling's potting medium moist, but not wet, by spraying the soil with your spray bottle. Keep your new plant in an area with bright light (though not direct sunlight) and temperatures between 65 and 72 degrees Fahrenheit. Ensure that the soil stays moist, but not wet, until the next spring (after the danger of frost has passed), when you can transplant it to its new home.

Propagating Saxifraga by Cutting

Gather your materials. You'll need a clean, sanitized, sharp pair of garden shears, rooting hormone, a pencil, and a 3-inch pot filled with well-draining compost or other organic material. If you don't have any potting medium on hand, you can make some. Just mix together equal parts (by volume) moss peat and horticultural-grade sand or grit sand.
In early summertime, choose the plant that you'd like to propagate. Cut one or more leaves off of the lower half of the plant, severing them near their base. Make a hole in your planting medium by pushing your pencil into the soil. Dip the end of the stem in rooting hormone, and plant it in your pot. Fill in soil around the cutting to support it, but do not pack it down too much.
Moisten with water, and ensure that the pot has good drainage. Your pot should be kept in warm, sunny conditions indoors (and not in direct sunlight). Water whenever your soil is dry under the top layer. After about four to six weeks have passed, your cutting should be rooted. When you notice new growth, you'll know you have roots.
Keep your new plant in an area with bright light (though not direct sunlight) and temperatures between 55 and 70 degrees Fahrenheit. Ensure that the soil stays moist, but not wet, until the next spring, when you can transplant it to its new home. Ensure that the last frost of the year has occurred before doing this, as it can seriously damage your new plant.

Propagating Saxifraga by Division
This type of propagation is relatively simple; you will need a clean shovel, mulch, fresh soil, compost and pots (only necessary if you will be saving divided plants for transporting elsewhere). Division is best done in very early spring (after the plant has entered dormancy, but before it has begun its new spring growth), and needs to be done every few years regardless of whether you have the goal of propagating the plants for best performance, especially if they are grown in a cramped space or container. To propagate by division, follow these steps:

Using a shovel, dig up your existing plant. Start from the outside and work your way in to avoid damaging the root(s). Once you have worked it up out of the ground, lay it out.
Start to tease apart the roots with your fingers. Once the roots are untangled, separate your plant into segments, ensuring that each one has at least one thick root section attached.
Prepare your pot(s) or new planting site(s) with amended, well-draining soil. You can either bring in new soil or simply amend your existing soil with compost to complete this task. Then, plant your divisions and water thoroughly.
Apply a thick layer of mulch over the new planting to protect it from cold weather as it acclimates to its new home. Then, enjoy watching it sprout in the next growing season.