Sundew plants, belonging to the genus Drosera, are carnivorous plants known for their glistening, dew-covered tentacles. These unique plants feature a mesmerizing appearance that attracts and traps insects, making them a fascinating addition to any plant collection. With over 194 species found globally, sundews exhibit remarkable diversity, thriving on every continent except Antarctica. Their sticky leaves are an extraordinary adaptation to their environment.
The Carnivorous Nature of Sundews
Sundews employ a “flypaper” trapping mechanism to capture prey. Their leaves are covered with stalked glands that exude a sweet, sticky mucilage. This “dew” attracts insects, which become ensnared upon contact. Once an insect is trapped, the sundew’s tentacles, and often the entire leaf, slowly coil around the prey, increasing contact with digestive glands.
This coiling motion can take minutes to hours, depending on the species and the size of the prey. The glands then release enzymes that break down the insect’s soft tissues, allowing the plant to absorb essential nutrients like nitrogen and phosphorus, which are scarce in their native habitats. Sundews evolved this carnivorous lifestyle as an adaptation to survive in nutrient-poor environments, such as bogs and fens, where typical soil nutrients are limited. This specialized feeding allows them to supplement their diet and thrive where other plants cannot.
Essential Sundew Care
Light Requirements
Sundew plants require abundant bright light to flourish and produce their sticky dew. Most sundews thrive in full sun, which also encourages their leaves to develop vibrant red coloration. If grown indoors, a south-facing window can provide sufficient light, or supplemental grow lights with at least 2,500 lumens are beneficial. Insufficient light is a common reason for sundews to stop producing dew or appear pale green. Aim for six to eight hours of direct light daily to maintain a healthy, dewy plant.
Watering Needs
Proper watering is paramount for sundew health, and they demand pure, mineral-free water. Distilled water, reverse osmosis (RO) water, or rainwater are the only suitable options, as tap water contains minerals that can accumulate and harm the plant over time. The tray method is recommended: place the potted sundew in a shallow tray and keep 1/2 to 1 inch of pure water in it at all times during the growing season. This ensures the soil remains consistently moist, mimicking their natural boggy habitats, and allows the plant to wick up water from below.
Soil Mix
Sundews require a specific, nutrient-poor, acidic soil mix. Regular potting soil or garden soil is detrimental because its rich nutrient content will harm or kill the plant. A common mix consists of sphagnum peat moss blended with perlite or silica sand. This combination provides the necessary acidity, excellent drainage, and moisture retention while remaining free of excess nutrients.
Humidity and Temperature
Most sundews prefer high humidity levels, ideally ranging from 50% to 70%, which encourages dew production. While some can tolerate lower humidity if gradually acclimated, a lack of humidity can cause the plant to stop producing dew. Placing the plant in a terrarium or using a humidity tray with pebbles can help maintain desirable moisture levels. Most sundews do well at room temperatures, generally between 60°F and 85°F (15°C to 29°C), though some tropical varieties prefer warmer conditions and temperate species may require a cool dormancy period.
Feeding Your Sundew
Sundews can catch their own food, especially if grown outdoors where insects are abundant. Indoor sundews can benefit from occasional supplemental feeding. Appropriate food includes small insects like wingless fruit flies, gnats, or freeze-dried bloodworms, and even crushed beta fish food pellets. Feed one or two leaves every two to three weeks, ensuring the food is small enough to be fully enveloped by the tentacles. Avoid feeding meat or large insects, as these can cause the leaf to rot.
Propagating Sundew Plants
Sundews can be propagated through various effective methods.
Leaf Cuttings
A healthy leaf can be cut or pulled from the parent plant and placed on moist sphagnum moss or floated in pure water. Small plantlets will eventually form along the leaf margins, which can then be separated and potted once they develop roots.
Seed Propagation
Sundew seeds are typically sown on the surface of a moist, suitable soil mix and kept in bright light. Some species may require cold stratification for germination.
Division
Division is also possible for clumping sundew species that naturally produce offshoots. These offshoots can be carefully separated from the main plant and repotted into their own containers once they are of sufficient size.
Troubleshooting Common Sundew Issues
Several common issues can arise when caring for sundews, but most have straightforward solutions.
- A lack of dew on the tentacles, for instance, frequently indicates insufficient light or low humidity. Moving the plant to a brighter location or increasing ambient humidity typically resolves this problem.
- Browning leaves or tentacles often signal stress due to excessive heat, improper watering, or mineral buildup from tap water. Ensuring the plant receives pure water consistently and is not exposed to extreme temperatures can prevent this.
- Stunted growth may point to a lack of light, inadequate humidity, or the absence of nutrient supplementation through prey. Addressing these environmental factors can help restore vigorous growth.
- Common pests like aphids, mealybugs, and thrips can also affect sundews, and these can often be managed by gently rinsing the plant with pure water or using an appropriate, non-toxic insecticidal soap formulated for carnivorous plants.