The Drosera capensis, commonly known as the Cape Sundew, is a widely cultivated and relatively forgiving carnivorous plant originating from South Africa. This species is often recommended for beginners due to its robust nature and simple care requirements. The ‘alba’ variety is a specific cultivar distinguished by its complete lack of red pigmentation, resulting in an entirely green and white appearance. This means the plant relies purely on environmental conditions, rather than color change, to indicate its health.
Light and Temperature Requirements
Light is a crucial factor determining the health and predatory ability of the Cape Sundew, especially for the ‘alba’ cultivar. Sufficient light is directly responsible for the production of the sticky mucilage, or “dew,” that coats the tentacles and traps prey. Without adequate illumination, the plant will fail to produce this dew.
The plant requires intense, bright light, ideally receiving six to eight hours of direct sun daily to thrive. A sunny, south-facing windowsill is generally the best natural location for indoor growers. If natural light is insufficient, high-output artificial grow lights, such as LEDs or fluorescent tubes, must be used. The lighting system should be positioned to provide at least 12 hours of intense illumination each day to mimic the plant’s native environment.
D. capensis ‘alba’ prefers a moderate temperature range, performing best between 50°F and 85°F (10°C to 29°C). While the plant can tolerate brief periods outside this range, consistently high or low temperatures can cause stress. It is a subtropical species, meaning it does not require a cold dormancy period like many temperate carnivorous plants. Protecting the plant from freezing temperatures is important.
Choosing the Right Substrate and Water Source
The selection of the growing medium and water source is crucial, as standard gardening products contain minerals toxic to the plant. Carnivorous plants evolved in nutrient-poor bogs and cannot process the salts and dissolved solids found in most tap water and commercial potting mixes. The presence of these minerals will rapidly burn the roots, leading to a decline in plant health.
The ideal substrate is an acidic, nutrient-free mixture, typically composed of 50% long-fiber sphagnum peat moss and 50% horticultural perlite or silica sand. Ensure the peat moss and perlite are free of added fertilizers, which are common in general-purpose gardening products. Rinsing the perlite and peat moss thoroughly before mixing helps remove fine dust or residual impurities. Use plastic containers, avoiding terracotta pots which can leach mineral salts into the substrate.
Only low-dissolved-solid water sources are acceptable for watering D. capensis ‘alba’. Acceptable options include distilled water, collected rainwater, or water purified by reverse osmosis (RO water). The water should have a total dissolved solids (TDS) reading of less than 50 parts per million (ppm) to prevent mineral buildup.
The most effective watering method is the “tray method,” which ensures the substrate remains consistently moist. This involves placing the plant’s pot into a saucer or tray that is kept filled with about one inch of purified water. The substrate wicks the water up from the bottom, maintaining the bog-like conditions. The water level should be replenished just as the tray dries out, but before the soil itself begins to dry.
Feeding, Repotting, and Propagation
While Drosera capensis ‘alba’ captures insects, the plant produces its own food through photosynthesis. Manual feeding is only required for plants grown indoors where natural prey are scarce. Appropriate food items include small insects, freeze-dried bloodworms, or fish food flakes. The prey must be small enough to fit entirely onto the sticky tentacles of a single leaf pad.
Feeding should be done sparingly, typically once or twice a month, feeding only one or two leaves at a time. Excessive feeding can stress the plant and may lead to mold or rot if the food item is too large. Never apply fertilizer to the soil, as this will cause root burn.
Repotting is generally necessary every one to two years to refresh the substrate. Over time, the peat component of the soil mix naturally compacts, which can restrict root aeration. Repotting is best performed during the spring or early summer when the plant is actively growing.
The Cape Sundew is one of the easiest carnivorous plants to propagate, frequently producing numerous plantlets from its roots and readily self-seeding. A highly reliable method is leaf cuttings, where a healthy leaf is cut close to the plant’s base. These cuttings can be floated in distilled water or laid flat on a bed of moist, pure sphagnum moss under bright light. Small plantlets will eventually form along the edges of the severed leaf.
Seed Propagation
D. capensis produces abundant seeds from its flowers. When sprinkled on the surface of the proper substrate, these seeds will germinate readily without needing cold stratification.