Sedum sexangulare

Care Guide: Planting, Soil & Watering

Overview: Sedum sexangulare (Tasteless stonecrop) is a hardy, drought-tolerant succulent that thrives in bright light and gritty, sharply draining soil. It stores water in its fleshy leaves, so it needs only occasional watering and quickly rots in heavy, wet ground.

Quick Care Requirements

Requirement	Ideal Condition
Planting Season	Spring in zones 3–5; spring to summer in zones 6–8; spring to autumn zones 9–10a; year-round in zone 10b
Growth Rate	Moderate
Soil Type	Light, sandy, well-draining soil — a cactus/succulent mix or soil opened up with grit
Water Need	Low to Moderate — let the soil dry out between waterings

Planting & Establishment

• Best Planting Season: Set out plants in the warmth of spring so the roots settle before winter; in the mildest zones the window stretches further (spring in zones 3–5; spring to summer in zones 6–8; spring to autumn zones 9–10a; year-round in zone 10b). In cold-winter areas grow it in containers that can be moved under cover.
• How to Plant:
  • Hole Preparation: Dig a shallow hole just wide and deep enough for the small root ball — these succulents are shallow-rooted and resent sitting in a deep, water-holding pocket.
  • Soil Amendments: Mix coarse sand, grit or perlite into the bed to sharpen drainage; aim for a lean, airy soil rather than a rich, moisture-retentive one.
  • Planting Depth: Set the crown level with the soil surface so the fleshy stems and leaves rest on top — never bury them, which invites rot.
• Growth Speed & Expectations: Expect moderate growth; as a spreading groundcover it knits together steadily into a low mat rather than shooting upward.

Soil, Watering & Drainage Care

• Soil Mix & Drainage Needs: Give it a light, well-aerated mix; in pots use a shallow, wide container of free-draining cactus/succulent soil with ample drainage holes. Waterlogged soil is the single biggest threat, quickly rotting the roots and stems.
• Watering Schedule & Technique:
  • Young / Newly Planted: Water lightly after planting and then only once the soil has dried, just enough to help new roots settle — overwatering now is the main cause of failure.
  • Established: Water deeply but infrequently, always letting the soil dry out completely first; established plants shrug off real drought.
  • Seasonal Adjustments: Cut watering back sharply in winter while the plant rests, and water a little more often only during prolonged summer heat.

Growing in Pots, Balconies & Indoors

Sedum sexangulare (Sedum sexangulare) is a low, mat-forming succulent, 5-15 cm (2-6 in) tall. The grower notes it is not a true houseplant, but it is excellent in outdoor containers and on a sunny windowsill. In pots it is easy and forgiving – a shallow, gritty container on a sunny sill, balcony or patio is all it asks.

Quick Details

• Container Size: Shallow and wide; minimum 5-8 L, only about 70-150% larger than the root ball
• Indoor Suitability: Not a deep-room houseplant, but thrives on a bright, sunny windowsill
• Best Spot: Full sun to part shade – the brightest spot available
• Soil & Drainage: Fast-draining cactus/gritty mix; never soggy
• Watering in Pots: Sparingly – let the mix dry out between waterings; overwatering is the main risk

Indoors & On the Windowsill

• Not a true houseplant: The grower marks it ‘No’ – like most stonecrops it needs strong, direct light that an ordinary room interior cannot supply.
• Windowsill: It does well on your brightest, sunniest windowsill (south or west facing) with several hours of direct sun; leggy, stretched stems signal too little light.
• Overwintering: Most creeping sedums are hardy and happier outdoors, but a prized pot can shelter on a cold, bright sill through a severe winter.

On a Balcony or Patio

• Light & heat: Ideal for a hot, sunny balcony – it shrugs off reflected heat from walls and paving. Give it the brightest spot and it will colour up beautifully.
• Rain & drainage: In prolonged wet weather move pots under cover; combined with cold, standing water is what kills these succulents, not drought.

Choosing the Pot, Soil & Long-Term Care

• Pot & drainage: A shallow, wide pot with strong drainage holes; skip a standing water saucer to avoid root rot. Terracotta breathes and dries fast (good for succulents), while glazed or plastic holds moisture longer.
• Potting mix: A gritty, free-draining blend – cactus mix or potting mix cut with sharp sand, perlite and a topping of gravel or lava rock.
• Feeding: Succulents need very little; a weak feed once or twice in the growing season is ample in a pot.
• Refreshing the mix: Container mix loses its drainage after a few years – replace it and pot on as the clump spreads.

Grower’s Container Tip

• Shallow and wide: pick a pot only about 70-150% larger than the root ball. A depth of 10-15 cm (4-6 in) is plenty – going deeper adds nothing. A minimum of 5-8 L works, but bigger is better.
• To keep the plant compact you can trim the roots and let them regrow into fresh space.
• Drainage is everything: use a free-draining potting mix, cactus mix or sandy soil, and add coarse grit – gravel, lava rock or pebbles. After a few years the mix stops draining well, so replace it with fresh mix.

Bloom & Flower Guide

Quick Details

• Bloom Season: Summer
• Flower Appearance: Yellow, five-petalled star flowers carried in clusters on short stems
• Edibility: Grown as an ornamental groundcover, not for eating

Detailed Blooming Overview

Tasteless stonecrop flowers in summer, raising sprays of small yellow stars above a fine, needle-leaved mat. The common name comes from its leaves lacking the peppery bite of some related stonecrops. It is a tough, drought-tolerant carpeter, and the bloom lights it up in the warmer months.

Flower Characteristics

• Yellow, star-shaped flowers with five petals.
• Held in clusters on stems above the foliage.
• Nectar-rich — a good draw for bees and other small pollinators.

Bloom Care & Thinning

• Managing the bloom: Shear off the spent flower stems once flowering ends to keep the mat neat.
• Pollination: The open flowers are easily worked by bees and hoverflies.

Pruning, Training & Seasonal Maintenance

Sedum sexangulare forms a very low, tight, evergreen carpet only 2–6cm tall, so pruning here means edging and light grooming rather than shaping a subshrub. It is hardy to zone 3, so unlike less cold-tolerant stonecrops, timing is driven by tidiness and spread control rather than frost risk. The safest window is early spring, before the new flush, with a second light pass after summer flowering to remove spent stems. Grooming has no effect on next season’s bloom.

Quick Pruning & Maintenance Specs

Pruning Tolerance	Low–Moderate
Primary Pruning Window	Early spring, before new growth
Secondary Maintenance Window	After summer bloom (deadheading)
Typical Frequency	Once or twice a year
Main Objective	Control spread at bed edges; remove spent flower stems
Young Plant Priority	Leave undisturbed to establish and knit together
Mature Plant Priority	Edge back over-spreading growth; refresh thin patches
Best Tool Type	Precision snips
Avoid Heavy Pruning During	Prolonged wet weather (rot risk)

Pruning by Plant Age & Size

Newly Established

Leave a newly planted patch alone except to remove any damaged stems; it needs full leaf cover to knit into a solid mat.

Young / Formative

No structural training is used; the plant self-forms its carpet. Light pinching can thicken sparse young patches.

Mature / Established

Once established, its vigorous creeping habit means the main task is trimming back runners at bed, path, or lawn edges before they root beyond the intended area.

Seasonal Pruning Schedule

Stage	Objective	Remove	Do Not Remove	Response / Impact
Pre-Growth / Early Spring	Tidy and edge the carpet before the growth flush	Dead or shriveled stems; runners past the bed edge	Healthy low rosettes	Encourages dense regrowth; no impact on summer bloom
Ongoing Sanitary	Remove spent flowers after summer bloom	Dried flower clusters	Vegetative growth	Tidier carpet; no bloom-timing consequence

Special Growth to Remove

• Creeping stems that have rooted beyond the intended planting edge
• Spent flower stems after summer bloom
• Any patches gone soft or mushy after wet weather

Container & Small-Space Pruning

In shallow pots or troughs, trim trailing stems back to the container edge regularly — because of its vigor, sexangulare will otherwise spill and root wherever it touches soil, including neighboring pots.

Tools

• Precision snips — for edging runners and removing spent flower stems

Tool Hygiene & Disease Risk

Routine care only — clean, sharp snips are sufficient; no notable transmissible disease risk beyond rot in waterlogged conditions.

Cut Placement & Technique

Snip runners cleanly where they cross the bed edge rather than tearing them free, which can uproot adjacent healthy mat.

Heavy Pruning & Rejuvenation

Hard rejuvenation is rarely needed since this species stays low and self-renews by creeping; a patchy mat is better refreshed by replanting healthy stem sections into gaps than by cutting back old growth.

Post-Pruning Care

No feeding is needed after trimming; let cut edges dry briefly before the next watering.

Common Pruning Mistakes

• Letting edging lapse, so runners root into lawn or neighboring beds
• Overwatering after a cutback, risking rot
• Pulling runners instead of cutting them, which uproots surrounding mat

When NOT to Prune

• During prolonged wet weather (rot risk)
• Immediately after transplanting divisions, until they root in

Recommended Tools (by task)

• precision_snips — the only cuts needed are on thin creeping stems and spent flower stalks

Pests, Diseases & Troubleshooting

Overview: Tasteless stonecrop is a hardy European mat-former resembling biting stonecrop but without the acrid taste, with six-ranked green leaves and yellow flowers. Like all stonecrops, Sedum sexangulare is far more often harmed by cultivation mistakes—above all overwatering—than by any pest. The insects it does attract (mealybugs and aphids under cover, slugs and snails outdoors) are few and easily managed by hand or with gentle organic sprays. Grow it hard in sharply drained gritty soil with strong light, water only when the soil is dry, and most problems never begin.

Quick Troubleshooting Overview

Issue / Pest	Main Symptom	Primary Solution
Mealybugs	White cottony tufts tucked into leaf axils and rosette centres, sticky honeydew and sooty mould	Dab with alcohol, rinse, then insecticidal soap or neem
Aphids	Clusters of soft green/black insects on new growth and flower stems, distortion and sticky sap	Blast with water, insecticidal soap, encourage ladybirds
Slugs & snails	Ragged holes and slime trails over the fleshy leaves, worst in damp weather	Hand-pick after dark, grit/copper barriers, iron-phosphate bait
Root & stem rot	Blackened, mushy, translucent stems that collapse at the base	Withhold water, improve drainage, cut back to firm tissue and re-root
Etiolation	Stems stretch pale and floppy with wide gaps between leaves	Move to much brighter light; behead and re-root compact tips
Sedum rust	Rusty-orange pustules on undersides of leaves and stems	Remove affected growth, improve airflow, sulphur if severe

Common Pests & Management

• Mealybugs (Planococcus citri / Pseudococcus spp.):
  • Symptoms: Slow-moving, soft insects coated in white waxy fluff, hiding deep in leaf axils, rosette centres and among trailing stems. They excrete sticky honeydew that turns black with sooty mould; heavy infestations stunt and yellow the plant. Do not mistake the cottony masses for the natural waxy bloom on the leaves.
  • Prevention & Control: Inspect new plants before introducing them and isolate any that are infested. Touch each colony with a cotton bud dipped in isopropyl alcohol, then rinse. For wider outbreaks spray insecticidal soap or neem oil, wetting the hidden crevices, and repeat weekly until clear. A bad potted infestation is best cured by unpotting, washing the roots (root mealybugs hide there too) and repotting into fresh gritty mix.
• Aphids (Aphis sedi and other Aphis spp.):
  • Symptoms: Dense clusters of soft green, grey or black insects on tender new shoots and especially on the flower stalks, causing curling and sticky honeydew. Aphis sedi is the stonecrop specialist and swarms flowering heads.
  • Prevention & Control: Knock them off with a firm jet of water, repeated every few days. Encourage ladybirds, lacewings and hoverflies, which clear light infestations on their own. If they persist, an insecticidal soap or a light neem spray in the cool of evening works well; avoid spraying open flowers to protect pollinators.
• Slugs & Snails (Deroceras reticulatum, Cornu aspersum):
  • Symptoms: Irregular holes chewed in the plump leaves and stems, tender new mat growth grazed away, and tell-tale silvery slime trails; damage appears overnight and in wet spells.
  • Prevention & Control: Keep the crown dry and the surrounding ground open. Hand-pick after dark by torchlight, set beer traps, and ring vulnerable plants with sharp grit, crushed shell or copper tape. Where pressure is high, scatter iron-phosphate pellets, which are safe around pets and wildlife.
• Vine weevil (Otiorhynchus sulcatus):
  • Symptoms: Adults notch neat bites from leaf margins at night; the real damage is done below ground by fat, legless, C-shaped white grubs that devour roots, causing sudden wilting and collapse of an otherwise healthy plant—most serious in containers.
  • Prevention & Control: Check the rootball of new plants. Water in a drench of beneficial nematodes (Steinernema/Heterorhabditis) into moist, warm compost to kill the grubs; repot survivors into fresh mix and remove any adults found at night.

Diseases & Fungal Issues

• Crown, stem & root rot (Pythium, Phytophthora, Fusarium, Rhizoctonia):
  • Symptoms: By far the commonest killer of stonecrops. Stems and the base of the plant turn black, soft, translucent and foul-smelling, then collapse; roots are brown and mushy. It follows soggy soil, buried crowns or cold wet conditions.
  • Treatment & Management: Prevention is everything—use a fast-draining gritty mix, pots with drainage holes, and water only when dry, never letting the plant sit wet. If rot appears, cut cleanly back into firm green tissue, let the cutting callus, and re-root it; discard badly rotted plants and the contaminated soil.
• Botrytis / grey mould (Botrytis cinerea):
  • Symptoms: Fuzzy grey-brown mould on leaves, stems and faded flowers in cool, damp, crowded conditions; affected tissue rots and drops.
  • Treatment & Management: Improve air movement, avoid overhead watering, and remove dead leaves and spent flower heads promptly. Thin congested growth; a copper or biological fungicide helps only if the underlying damp is corrected.
• Sedum rust (Puccinia spp.):
  • Symptoms: Powdery rusty-orange to brown pustules on the undersides of leaves and on stems, with yellow blotches above; heavy attacks weaken and disfigure the plant.
  • Treatment & Management: Pick off and destroy infected leaves at first sign, space plants for good airflow and keep foliage dry. Persistent cases respond to a sulphur or other organic fungicide applied to protect new growth.
• Powdery mildew (Erysiphe/Golovinomyces spp.):
  • Symptoms: A less frequent, white powdery film on leaves and stems in warm, humid, still air, sometimes distorting new growth.
  • Treatment & Management: Increase spacing and airflow, remove affected parts, and treat if needed with a potassium-bicarbonate or sulphur spray.

Growing Difficulties & Abiotic Problems

• Overwatering & waterlogging:
  • Cause & Symptoms: The single most common problem—leaves and stems turn yellow, translucent, soft and mushy, and the plant rots from the base. Caused by too-frequent watering, water-retentive soil or pots without drainage.
  • Correction Strategy: Let the soil dry fully between waterings, switch to a gritty free-draining mix, and always use a pot that drains. When in doubt, water less—a stonecrop recovers from drought far more readily than from rot.
• Etiolation (stretching for light):
  • Cause & Symptoms: In too little light the stems elongate, grow pale, and the leaves space out and point down, losing the tight compact form and any bright colour.
  • Correction Strategy: Move to the brightest position available or add a grow light. Stretched growth will not re-compact, so behead the plant and re-root the tidy tips for a fresh, dense start.
• Vigorous spreading:
  • Cause & Symptoms: It forms fast, dense low mats that root as they go and can crowd out smaller neighbours or spread beyond bounds.
  • Correction Strategy: Use it where its vigour is an asset (green roofs, paving, gravel) and pull or lift surplus mats, which lift away easily.
• Sunburn / scorch:
  • Cause & Symptoms: A plant moved abruptly from shade or indoors into strong summer sun develops bleached white or brown scabby patches on the most exposed leaves.
  • Correction Strategy: Harden it off over one to two weeks, increasing sun gradually. Scarred leaves will not heal but new growth adapts; provide light afternoon shade in the hottest, driest climates.

What Helps — Products & Tools

For this stonecrop keep the toolkit simple and gentle: isopropyl alcohol on a cotton bud for spot-treating mealybugs, insecticidal soap and neem oil for aphids, scale and mites, and—outdoors—iron-phosphate slug pellets, copper barrier tape or sharp grit against slugs and snails. Beneficial nematodes deal with vine weevil grubs in pots, sulphur or potassium-bicarbonate spray checks rust and mildew, and a bag of horticultural grit or pumice is the best long-term insurance against the rot that causes most losses.

Propagation Guide

Sedum sexangulare, a very low, mat-forming stonecrop, propagates most easily from stem or leaf cuttings in free-draining soil; seed also works and gives plants similar to the parent, but takes longer to establish a mat. Vegetative propagation is not strictly required, but it is easier and faster than seed, and overall this is an easy plant to increase.

Quick Propagation Specs

Best Propagation Method	Stem or leaf cuttings
Alternative Methods	Seed sowing; simple layering (pinning a stem into soil)
Propagation Difficulty	Easy
Seed True-to-Type	Usually true-to-type (species, not a named cultivar)
Vegetative True-to-Type	Yes
Best Propagation Season	Spring
Seed Germination Time	2–4 weeks
Cutting Rooting Time	Typically a few weeks under warm, lightly moist conditions
Seed Sowing Depth	About 0.5cm (0.25in)

Growing from Seed

Seed Handling & Viability

Keep saved seed dry, dark and at room temperature until sowing.

Sowing Season

Spring is best; in warmer hardiness zones sowing can extend into summer or autumn, but avoid the peak of summer heat.

Sowing Depth & Orientation

Sow shallowly, about 0.5cm (0.25in) deep.

Germination Conditions

Use a light, sandy, well-ventilated, free-draining mix in bright light. Keep evenly moist without waterlogging — overwatering is the main cause of poor germination, though letting the bed dry out also causes problems.

Germination Time

Germination typically takes about 2–4 weeks.

Seedling Care

Keep seedlings in bright light with moist, well-ventilated soil. Space roughly 2x2cm (1x1in) when pricking out, and allow 20–30cm (8–12in) between plants at final spacing given this species’ spreading habit.

Stem Cuttings

Cutting Type

Short stem-tip cuttings.

Best Timing

Spring through summer.

Cutting Preparation

Let the cut end sit in a shaded spot for a few days to heal and dry slightly before inserting into soil.

Rooting Setup

Insert into free-draining, sandy soil; keep lightly moist, never soggy.

Rooting Hormone

Not necessary; this species roots readily unaided.

Rooting Time

Roots typically form within a few weeks.

Leaf & Root Cuttings

Leaves can also be used: cutting cleanly at the leaf base tends to work better than snapping it mid-leaf, though a mid-leaf piece can still root. Let it heal and dry in shade for a few days, then set the cut end onto moist, free-draining soil, keeping it lightly moist until a new plantlet forms at the base.

Air & Ground Layering

Given its low, spreading growth, simply bending a stem down and covering part of it with soil while still attached to the parent works well; once that section has rooted, sever it and grow the new plant on its own.