Sundew – Drosera
A truly international plant, the Drosera genus is the most diverse of all carnivores with nearly two hundred different Sundew species and hybrids found globally. From Cape sundews, to subtropical sundews, temperate sundews, fork-leafed sundews, tropical sundews, woolly sundews, pygmy sundews, tuberous sundews, climbing tuberous sundews, fan-leafed tuberous sundews, rosetted tuberous sundews, South African Winter-growing sundews, and the King sundew, each is truly a one-of-a-kind plant with a unique beauty. All boast delicate flowers and carnivorous habits with glittering dewdrops that give them their fascinating appearance. Your sundew will definitely turn heads and prompt friendly questions if you keep it in an observable place. Who knew that you could get rid of some of those pesky gnats where you live, and improve the feng shui of your house all in one fell swoop?
Biology of a Sundew
The trap
All Sundews capture prey by using glistening drops of “dew” for which the plant derives its common name. The shape, size, color, and mobility of the leaves vary across varieties yet each is densely covered with small tentacle-like hairs with singular drops of dew at their tips. The multitude of dew drops (healthy plants can have hundreds of dew drops) make the sundew a breathtaking beauty and a sticky death trap for small insects.
Some species of Drosera can be very hearty, proliferating to a point where they become carnivorous weeds popping up where you don’t necessarily want them. This is partially driven by branching root systems and robust seed production, but also from leaves that can, themselves, sprout entirely new plants if they touch soil. What a special plant!
Sub-soil biology & requirements
Being such a diverse genus, sub-soil characteristics of sundews vary widely. Below we’ll highlight each species:
Flowers
Sundew flowers vary dramatically in seasonal timing, shape, size, quantity, and the amount of seed produced, but most are beautiful shades of white, pink, or red and all share common reproductive structures.
Timing for Drosera flowering varies by species and is dependent on what part of the world they originate from and have adapted to. For instance, many will grow alongside other seasonal carnivores flowering around springtime, while others like tuberous sundews will flower between October and December only after they’re adjusted to the northern hemisphere.
A picture’s worth 1000 words:
Many Sundews will self-pollinate when the flower closes, but you’ll see better results if you manually assist the process. Pollen from anthers needs to be transferred to the stigmas. We suggest using something like a toothpick for this. Once pollinated, the pedals will frequently close or fall off and the ovary will begin to swell as seed production begins. The seed pod will take several weeks to mature before viable seed can be collected.
Even with the large array of reproductive methods employed by Drosera, seeds produced by flowers are often the most prolific means of propagation. You have plants like Drosera capensis that will flower and set seed until your entire carnivorous plant collection is infested. There are some exceptions, however – varieties like tuberous sundews will rarely produce seed in cultivation, and pygmy sundews can reproduce more prolifically from gemmae than seed.
Store seeds that won’t immediately be propagated in air-tight jewelers bags or small paper envelopes and refrigerate them. Different Drosera seeds can look very similar, so remember to label your seed packages with the name of the parent plant so that they’re easy to identify when it comes time to germinate.
Where to find Sundews in the wild
The shorter list would include locations around the world where sundews aren’t found. You will discover Drosera on almost every continent, including places in Siberia and Alaska that you’d prefer to avoid as a warm-blooded mammal. Of course, you also find sundews in the tropical wonderlands of Queensland and Brazil. Then we have the bogs of North America and Europe, and southern tips of South American and New Zealand. Click and drag around the map below for a preview of locations.
Cultivation, growing techniques & propagation
Most species do great in 1 part sand
to 1 part peat
, with a few exceptions preferring a sandier mix. Some do better in long-fibered sphagnum moss
.
Drained plastic pots
are a safe bet, but some do well in undrained, glazed ceramics
or glass pots. For drained pots, use water saucers
to maintain soil moisture. Many varieties will eventually form clumps of plants that should eventually be divided and put into separate pots.
Use distilled or reverse osmosis water. This can be inexpensively purchased in most grocery stores, or you can invest in a reverse osmosis (RO) filtration system
that hooks up to a sink (bonus – this also provides great drinking water for humans and pets). Keep the plant in a water tray and fill this tray to maintain wet-to-waterlogged soil. Remember that some species have dormancy periods requiring soil to temporarily dry out.
Sundews enjoy full-to-part sun. Brighter conditions will promote brighter coloration in some species, genotype-permitting. I’ve grown many species with great success in direct, sunny Southern California light.
Large outdoor plants will frequently do what they do best, and snag their own prey like mosquitos, flies, spiders, moths, and crane flies/mosquito hawks. For those indoor plants that require dietary supplements, small ants, gnats and wingless fruit flies
work well.
Completely avoid fertilizing Drosera adelae, D. schizandra, and D. prolifera. Remember, these plants grow naturally in nutrient poor soils – a major reason why they evolved traps to catch insects as their source of nutrients. Fertilizing can burn roots and kill the plant, but advanced growers may foliar feed (applying only to the leaves of the plant) monthly with a diluted (1/4 strength) epiphytic or acid fertilizer. Maxsea
is a good option. This is risky for a beginner and not recommended. As long as you keep your plants fed with bugs, they will be happy.
Transplant during, but towards the end of, dormancy. Many sundews will be fine in one pot for many years.
Sundews can produce offshoots and develop into clumping plants. The effect is beautiful – a shimmering sea of foliage. You can choose to separate these clumps and repot them towards the tail-end of their dormancy period. Do make sure that each crown of leaves has its own root system before dividing.
Leaf Cuttings:
Most Drosera are great candidates for leaf cuttings (except Drosera burmanni and D. regia… darn). Cuttings will result in larger plants faster than most seed-grown plants.
To take leaf cuttings, first sterilize a razor blade or sharp shears (bonsai shears work great) using isopropyl alcohol. Use these to cut loose one or more sundew leaves close to the plant’s main stem. We find the best method for encouraging root and foliage growth from these cut leaves is to simply float them sticky-side-up on purified water in a closed plastic or glass container. Place the container in a lit area and swap in fresh water if algae begins to grow. After a few weeks, you’ll notice bumps on the surface of the leaves which will turn into growing points. Roots will sprout from the bottom of the leaves. After they have sprouted, transfer them to a new home in a pot with soil. Keep the soil moist, and the roots will take hold with the growth point developing into a full plant.
Root Cuttings:
Similar to leaf cuttings, Drosera root cuttings will result in larger plants, faster – often fully mature plants in one growing season. This technique works best with plants like forked sundews, rosetted subtropicals, D. regia, and cape sundews, that have robust, thick root systems.
To take root cuttings, remove the sundew from soil and simply cut off 1.5″-3″ of healthy roots. The best time to do this is during a normal repotting/transplantation towards the end of a dormancy period (if the plant has one). Lay the cut roots horizontally on soil and cover with another 1/2 inch of soil. Keep the cuttings covered with a humidity dome, in bright light, wait several weeks, and viola! You’ll have wee-sundews bursting through the surface of your soil. After a few leaves have formed, remove the humidity dome and place in a sunny location.
For Drosera species that produce seed in cultivation, fertilization and propagation are straight-forward. See the section “Seed creation” above for details on pollination and seed storage.
Sow all sundew seeds in late winter/early spring except tuberous sundew and winter-growing seeds which go in the ground in early autumn. Spread seed sparsely across the plant’s preferred soil and do not cover with soil. Use a seed tray
and cover with a humidity dome, or place in a plastic bag to keep humidity high. After sowing, stratify the seeds by providing several weeks of chilly, damp conditions. Be prepared with fungicide to quickly quell any damp-off (fungus that attacks germinating seeds) flair ups.
Once stratification is complete, move containers to bright but indirect light (avoid overheating), and wait four-to-eight weeks for sprouting. Once greenery appears, remove the humidity dome and enjoy your new plants! Once they have a few leaves, you can transplant them from seed trays to permanent pots, but be gentle!
Sundews do great in tissue culture via sterilized seed and cuttings.
As efficient as sundews are at catching insects, aphids are a pest that can harm them. Infestations are best treated early with carnivorous-plant-safe insecticides like Ortho
. Fungus can also attack during moist, low-light winter conditions and can be treated with fungicide. Physan
works well against most fungi that attack carnivorous plants. Avoid soap-based insecticides on Drosera.
Because sundews grow in varied climates around the world, you’ll need to adjust climate controls based on the species’ origins. Conditions span the spectrum – Mediterranean, tropical, sub-tropical, warm-temperate, temperate, and cold-temperate.
If your outdoor climate mimics the native habitat of your sundew, you’re set. The sweet-spot to grow the widest variety of Drosera is in Mediterranean, subtropical, and warm-temperate climates.
Cool and warm houses will meet most sundew needs, but consider the origins of your plant and if your greenhouse recreates preferred climate conditions.
Most are great candidates for terrariums and enjoy bright florescent
or LED lighting
. Take into consideration the matured size of your sundew, and if a terrarium is enough space.
Subtropical species and cape sundews will handsomely adorn sunny windowsills. In more humid windowsills monstrous plants like Drosera multifida and D. regia will thrive.
You can grow many sundews alongside Venus flytraps (Dionaea) and North American pitcher plants (Sarracenia) in bog gardens. It’s a 1-2-3 combo of carnivorous cousins!
Sundew species & hybrids
Drosera schizandra
You'll fall in love with the heart-leafed sundew, Drosera schizandra! That is, if you can figure out how to keep it happy... It is a beautiful and unusual specimen, and one of the few carnivorous plants that grows on the rainforest floor!
Drosera prolifera
I'm not sure why this sundew isn't more common in collections; it's literally named for its spectacular ability to proliferate. Along with Drosera adelae and Drosera schizandra, it is one of the “Three Sisters from Queensland” as coined by Peter D'Amato in The Savage Garden.
Drosera adelae
Drosera adelae is one queen from Queensland that can be a crown jewel in any collection. It's quick to grow, quick to self-propagate, and produces dew like it's going out of style.
Drosera filiformis
I've heard Drosera filiformis referred to as nature's anti-aircraft gun for its ability to snipe flying insects out of the air. It's more commonly called the thread-leaved sundew due to its slender, filamentous leaves that reach towards the sky in an effort to tempt low-altitude insects into taking a detour to Sticky Town.
Drosera gigantea
"The giant sundew," indeed! This erect perennial tuberous sundew is one of the largest 'dews around, growing up to 3 feet (0.9 m) in height and branching like a carnivorous tree. Neat.
Drosera scorpioides
A titan among tots, D. scorpioides is commonly known as the shaggy sundew and hails from Australia. Even the darn pygmy plants want to kill you in Australia...
Drosera spatulata
known as the spoon-leaved sundew because of its' wee spoon-shaped leaves. The Latin name literally translates to "spatula shaped." One may look like teaspoons, another soup spoons... you get the idea.
Drosera regia
With 2 foot (0.6 m) leaves the King Sundew, Drosera regia, has earned its grandiose name. It is an archaic species and one of the oldest to survive to modern times.
Drosera capensis ‘Narrow Leaf’
Drosera capensis 'Narrow Leaf' This is your typical "common" capensis. Drosera capensis 'Narrow Leaf' is an incredibly hearty sundew that I have found hard [...]
Drosera binata var. dichotoma ‘Giant’
A monster of a forked sundew, D. binata dichotoma 'Giant' generates forked sundew leaves up to two feet long with four to twelve forks. Since individual leaves fan out from the central growth point, you can end up with 4 foot sundews!
Drosera capensis ‘Wide Leaf’
Cape Sundews hail from South Africa, and are some of the heartiest Drosera around. They're easy to grow, producing bountiful flowers atop long flower stalks and thousands of seeds - often becoming weeds growing amongst your other carnivores.
Add A Missing Plant
Are we missing a species, hybrid, subspecies, or plant variety? Help us improve our carnivorous plant database by submitting your own!
