Tasteless stonecrop

Tasteless stonecrop: how do you recognise it?

Habit

Dense, creeping mat 5–10 cm tall and 30 cm wide or more, with stems that root along the ground.

Foliage

Small (3–6 mm), fleshy, narrowly cylindrical and blunt, bright to soft green; the leaves sit in six rows along the stem. Evergreen.

Flower

Yellow stars in small, branched clusters, in June and July, on stems about 10 cm tall.

Look-alike

Resembles biting stonecrop (Sedum acre), but the leaves are longer, finer and softer in appearance and sit in six rows.

Roots

Fine and shallow; any piece of stem that touches the soil can root.

Flowering: June–July · Plants: March–May and September–October

Why grow it?

• Dense, evergreen carpet for the poorest, sunniest spots where almost nothing else will grow.
• Flowers in June and July with yellow stars that attract bees and other insects.
• Bright green foliage that stays all year, even in winter.
• Perfect for paving joints, green roofs, gravel gardens, rock gardens and containers: no water, feeding or pruning.
• Roots easily, so broken pieces quickly fill bare patches.

Tasteless stonecrop: where does it grow best?

• Full sun is best; in light half shade it grows looser and flowers less.
• Poor, well-drained soil: sand or loam, preferably mixed with grit or gravel. Acid to chalky soil is fine.
• Dry to normal: in heavy, wet soil it rots, especially in winter.
• Plant 20–30 cm apart; the mat closes within a season or two.
• Do not put it right next to fine, small rock plants: the carpet can smother them.

Light

Sun

Soil type

Sand or loam

Acidity

Not fussy

Moisture

Dry

Size

0.08 m tall, 0.3 m wide

Hardiness

Hardy (to -30 °C)

Goes well with

• Biting stonecrop: Yellow flowers and peppery leaves in the same dry, sunny spot; together they make a rich roof or gravel carpet.
• Houseleek: Rosettes that contrast with the fine green carpet.
• Creeping thyme: Scented carpet with pink flowers on the same poor soil.
• Pinks: Low kinds with pink or white flowers above blue-grey mats, on the same dry, sunny soil.

Tasteless stonecrop: when and how to plant it?

Plant in March–May and September–October.

1. Plant in March–May or in September–October, when the soil is neither frozen nor waterlogged.
2. Remove weeds and open up heavy soil with coarse sand or fine gravel. Do not add compost or fertiliser.
3. Set pieces of mat 20–30 cm apart, at the same depth as in the pot or tray, and firm them in.
4. Water once after planting, then only in prolonged drought in the first year.
5. If you like, spread a thin layer of grit or gravel around the plants; do not use a moisture-holding mulch.

Care

Water

Not needed once established. Too much water, especially in winter, makes the stems rot.

Feeding

Avoid: on rich soil the mat becomes soft, leggy and less dense.

Weeding

Weed regularly in the first year; once the mat is dense it lets few weeds through.

Spent flowers

They can stay. Cut them off after flowering if you want an even green carpet.

Keeping it in check

Trim the mat back where it creeps over paving, lawn or small plants; loose pieces root elsewhere.

Tip: Set it on poor, well-drained soil and never feed it: the mat then stays dense and low. A piece of stem pushed into a joint or laid on a roof is enough for it to root.

Tasteless stonecrop: when to prune it?

When: Pruning is not needed. If you like, remove dead pieces and old flower stems in March–April.

How:

• Cut spent stems with scissors right down to the mat.
• Remove brown or rotting pieces by hand.
• Pull back edges that spread too far and use the pieces for new spots.

Caution: The carpet spreads steadily and can smother small plants and paving joints: keep an eye on the edges.

Pruning calendar and basic rules

Propagation

Cuttings

From March to September: break off pieces of stem 3–5 cm long and lay them on poor, sandy soil; they root by themselves.

Division

In spring or September, lift a piece of mat with roots and plant it in a new spot.

Seed

In spring, sprinkle the very fine seed on sandy soil and press it in lightly without covering it.

Tasteless stonecrop: how does it get through the winter?

Hardy to −30 °C.

• Fully hardy to about −30 °C: no protection needed in Belgium.
• The foliage stays green all year; in hard frost it may darken slightly without harm.
• In pots and troughs: ensure good drainage and do not stand the pot in a saucer of water, because winter wet is more dangerous than frost.

Diseases and pests

• Rot: Soft, brown stems after a wet winter or in heavy soil. Improve drainage with sand or grit, or move the plant to a drier spot.
• Long, floppy growth: Too much shade or too much feeding. Give more sun, stop feeding and cut back the leggy stems.
• Bare patches: They appear after wet spells or trampling. Press pieces of stem into the soil to fill the gaps.
• Weeds: Grass and weeds settle in a young mat. Pull them out by hand before they set seed.

Through the year

• March: Plant. Remove dead pieces and old flower stems.
• April: Plant or divide. Lay cuttings.
• May: Plant. Weed young plantings.
• June: Flowering begins. No water or feed needed.
• July: Yellow star-shaped flowers. Bees visit the blooms.
• August: Cut off spent stems if you like. Trim the edges.
• September: Plant or divide.
• October: Plant. On wet soil, watch for rot.
• December: Rest. The green carpet stays in place.

Good for wildlife

Bees

Nectar and pollen for honeybees and wild bees.

Did you know?

• The species name sexangulare means six-angled and refers to the six rows of leaves along the stem.
• Its English name, tasteless stonecrop, points to the mild foliage; biting stonecrop, by contrast, tastes peppery.
• Like white stonecrop, it is among the plants often used on extensive green roofs.