Houseplant · Droseraceae
Cape Sundew
Drosera capensis
Give it full sun and pure rainwater, and the Cape sundew glitters with fresh insect-catching dew all year long.
Full sun
Every 1–3 days
41–86°F · 5–30°C
180–365 days
Overview
Here is a houseplant that hunts for its supper. The Cape sundew hails from the bogs of South Africa and catches insects to top up what the poor soil never gives it. Every leaf bristles with red dew-tipped tentacles that sparkle like nectar and pull in gnats and flies, which land, stick fast, and dissolve over time. It joins the family Droseraceae and stays pleasantly small, forming a tight little rosette just a few inches wide.
The very trait that makes it thrilling also gives it two firm rules, and nailing them is half the fun. This plant grew up in nutrient-poor, acidic ground, so ordinary potting soil and fertilizer are off the table for its roots. Water plays by the same rule: tap and mineral water pack salts that build up and poison it, so distilled, reverse-osmosis, or rainwater wins every time.
Sort out those two rules and the Cape sundew rewards you as one of the easiest carnivorous plants going. It powers along on a bright windowsill through every season and flushes a knockout deep red under strong light. Better still, it self-seeds with real gusto, so one plant quickly turns into a whole windowsill of them.
Care
The short version: hand it the brightest sun in the house, keep the pot standing in mineral-free water so the peat mix never dries, and steer clear of feeding the roots or pouring anything but distilled, RO, or rainwater.
Light
Hand the Cape sundew the brightest spot going, ideally several hours of direct sun on a south-facing sill. That strong light fires up the red in the tentacles and locks the rosette into a tight shape, while a dim corner turns it pale and leggy. Short on sunny windows? A strong grow light picks up the slack with ease.
Water
This is the part that decides everything. Pour only distilled, reverse-osmosis, or rainwater, because the salts in tap and mineral water pile up and kill carnivorous plants. Stand the pot in a tray holding 1 to 3 cm of that mineral-free water so the peat mix stays drenched, and back off only a touch in winter, never letting it dry out.
Soil
Pot it in a lean, acidic carnivorous mix, roughly equal parts peat moss or live sphagnum with sand or perlite, sitting at a pH near 4.0 to 5.5. Keep ordinary potting soil, compost, and any fertilized blend far away, since they scorch the roots.
Temperature
Temperature barely fazes this plant, which cruises along anywhere from about 41°F to 86°F (5°C to 30°C). Everyday room temperature keeps it going all year, and it skips the cold winter rest that trips up some carnivorous plants.
Humidity
It thrives with the air on the humid side, around 50% to 80%, and the windowsill water tray bumps that up on its own. It shrugs off average household air better than most carnivorous plants, though a really dry room can slow the dew.
Feeding
Skip feeding the roots entirely. The plant came up in nutrient-poor bogs, so soil fertilizer torches its roots, and it grabs its nitrogen straight from the gnats and flies it snags on its dew. Set indoors, it usually catches everything it needs without any help.
Pruning
There is barely any work here. Just clip off any fully blackened or dead leaves and spent flower stalks at the base with clean scissors to keep it sharp. Leave the sticky dew right where it is, since wiping it away strips the plant of how it catches its meals.
Repotting
Refresh it every 1 to 2 years in spring by shifting it into new carnivorous mix. Jump on it sooner if the roots start circling the pot, the rosettes crowd into a clump, or the old mix breaks down and stays compacted.
Size & spacing
This is a compact little grower, a rosette that tops out at just 2 to 14 inches (5 to 35 cm) tall and spreads 3 to 6 inches (8 to 15 cm) across. That small footprint means it slots onto any bright windowsill with room to spare.
Troubleshooting
Nearly every sundew snag boils down to two culprits: the wrong water or too little light. The leaves flag the problem early, so a quick glance points you straight to it. Match your symptom below and jump on the fix before the plant loses ground.
The dew dries up on the leaves
Dry, dull tentacles almost always trace back to the wrong water, since tap and mineral water dump salts that poison a carnivorous plant. Weak light or bone-dry air can throttle the dew too. Switch to distilled, reverse-osmosis, or rainwater, flush the mix to sweep the salts out, then move the plant somewhere brighter and more humid, and the fresh leaves will glisten right back.
Fix:
- Switch immediately to distilled, RO, or rainwater
- Flush the mix with mineral-free water to leach out salts
- Move to brighter light and raise humidity
Leaves turn black and die back
Blackening leaves usually flag mineral buildup from the wrong water, though a fresh repot or the plant's own leaf cycle can trigger it too. Watch which leaves drop: if only the old ones darken while healthy new growth rockets up, that is just normal turnover. Fix the water, snip the dead leaves at the base, and hold steady wet, bright conditions while it rebounds.
Fix:
- Correct the water source to mineral-free water
- Remove blackened leaves at the base
- Maintain stable wet conditions and bright light during recovery
Pale, stretched growth losing its red
A sundew gone green and leggy is flat-out starved for light. Give it full sun and the tentacles and leaf blades blaze deep red while the rosette pulls in tight and compact. Move it to a sunnier window or under strong grow lights, and crank up the brightness over a few days so the leaves do not scorch.
Fix:
- Move to a sunnier window or add strong grow lights
- Acclimate gradually to avoid scorching
Toxicity
Great news for a home full of pets and kids: the Cape sundew is not toxic to anyone. The sticky dew coating its leaves is a harmless mucilage that might cling to a finger or a paw for a second, then wipes clean with zero irritation. The one thing to keep an eye on is the water tray, which an inquisitive pet could knock over.
Safe for
People · Cats · Dogs · Horses · Rabbits · Livestock · Birds
Cats Safe
A curious cat can sniff or nibble a sundew and stay perfectly fine, since the plant packs no toxin. A bit of dew might cling to the whiskers for a moment, but it washes off and leaves no irritation.
Dogs Safe
Dogs are totally in the clear here. If one chomps a leaf, expect nothing worse than a harmless dab of sticky residue on the muzzle.
Horses Safe
Nothing in this plant would trouble a horse, and its tiny size makes it an unlikely mouthful in the first place.
Rabbits Safe
Rabbits can hang around a sundew with no worries at all. A nibbled leaf brings zero poisoning, just the odd smear of dew on the fur.
Livestock Safe
Goats, sheep, and cattle face no risk from the plant. The dew is sticky, not harmful, and the tiny rosette gives them almost nothing to graze.
Birds Safe
Birds come to no harm around a sundew. Those glistening tentacles are built to catch gnats and flies, never to threaten anything bigger.
People Safe
The plant is safe to handle, and the dew is a simple mucilage that wipes right off skin. Leave it on the leaves, though, since that dew is how the plant feeds itself.
The dew is a harmless sticky mucilage; it may briefly cling to skin or fur but causes no irritation. Avoid wiping it off the plant, as it is the trapping mechanism.
Varieties
Drosera capensis shows up in a handful of easy-to-find forms that split mainly by leaf shape and color. Grab any of these three and you are off to a flying start.
Drosera capensis 'Typical'
The most widely grown form sports narrow green strap-like leaves tipped with red dew, and its easy streak makes it the perfect one to kick off with.
Drosera capensis 'Alba'
This all-green form has dropped its red pigment, so the tentacles stay pale and the flowers open white.
Drosera capensis 'Red'/'Wide Leaf'
Blast this form with bright light and it pushes out broader leaves washed a strong red straight across the blade.
How to propagate
Few plants make copies of themselves as eagerly as the Cape sundew, and that is a blast to work with. Spin up new plants from a single leaf, from the seed it flings around on its own, or by splitting an older clump.
Leaf cuttingsEasy
Spring to summer during active growth · 4-10 weeks for plantlets to form, several months to reach size
Snip a leaf cutting in spring or summer while the plant is charging along. Lay a healthy leaf on damp mineral-free carnivorous mix or float it in mineral-free water, and tiny plantlets pop up along it within 4 to 10 weeks, then spend several more months bulking up to full size.
SeedEasy
Spring; surface-sow on damp peat mix in light · 2-6 weeks to germinate, several months to a mature rosette
Since Drosera capensis pollinates itself and flings seed everywhere, this is the easiest route by far. Surface-sow on damp peat mix in spring and leave it uncovered, because the seed needs light to fire up. Germination rolls in at 2 to 6 weeks with no cold treatment, and a mature rosette follows a few months on.
DivisionEasy
Spring at repotting · A few weeks to re-establish
Come the spring repot, split an established clump into separate plants. Gently pry apart the offset rosettes with their roots attached, pot them into fresh carnivorous mix, and they bounce back within a few weeks.
Myths
Sundews have to be hand-fed insects or they will starve.
A sundew powers itself with photosynthesis like any green plant, and it snags plenty of small insects all on its own. Feeding it by hand is optional, never a requirement, and an indoor plant usually traps every gnat it needs.
You should mist or wipe the leaves to clean off the sticky dew.
That dew is the plant's prey-trapping mucilage, so wiping it off yanks away the exact thing that feeds it. Misting with tap water does double harm, piling on the minerals that poison carnivorous plants.
Carnivorous plants need rich soil and fertilizer to thrive.
Sundews came up in nutrient-poor, acidic bogs, and their roots just cannot take the load. Ordinary soil and fertilizer burn the roots and kill the plant, so a lean peat-and-sand mix is the only safe way to grow one.