Cold-Hardy Sundew Care

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Get the straight facts from the guys who have grown and propagated thousands of carnivorous plants every year since 1995.
Grow Cold-Hardy Sundews
The United States is home to several species of cold hardy sundews: Drosera anglica, D. brevifolia, D. filiformis, D. intermedia, D. linearis, D. capillaris, D. rotundifolia, and D. tracyi. While there are certain idiosyncrasies that characterize some of the varieties, general care is the same for each of them. Use the following as a guideline to growing cold hardy sundews.
Drosera rotundifolia
Drosera filiformis
Drosera filiformis x intermedia

Where to Grow
Cold hardy sundews grow best outdoors as a container or potted plant on a sunny deck or patio. You may also grow them in a pond or fountain, but keep the crown of the plants above water. Because of their specific soil requirements, avoid planting them directly into the ground.

During the growing season, grow cold-hardy sundews outside in partial to full sun. Provide 4 or more hours of direct sunlight for vigorous growth.

Because D. filiformis and Venus flytraps have the same growing requirements,
they can grow together in the same pot.

Heat Tolerance
Most cold hardy sundews, such as Drosera filiformis, Drosera intermedia, and Drosera trayci, tolerate the summer heat well. They originate from an area where temperatures above 90°F (32°C) commonly occur in summer. Other sundews, such as Drosera rotundifolia, prefer mild temperatures.

Sundews require mineral-free water. If your tap water is relatively pure (less than 50 parts per million in dissolved minerals), then you can safely water your sundews with it. Otherwise, use bottled distilled water. Keep the soil wet at all times. You can do this by setting the plant in small amounts of standing water, no more than halfway up the pot.

Use a soil mixture of 1 part peat moss and 1 part perlite. Never use potting soil, compost or fertilizer; these ingredients will kill your plant.

Winter Care
Cold hardy sundews require 3-4 months of winter dormancy triggered by cold temperatures (below 50°F or 10°C) and shorter daylight hours. As your plants enter dormancy, they will drop their leaves and stop growing altogether. While dormant, your plant can withstand overnight frosts down to 20°F (-7°C). As long as temperatures rise above freezing during the day, you don't need to protect your plants. However, even while dormant, your plant will still need to sit in a small amount of standing water to prevent its soil from drying out.

If you live in zones 7 and 8, protect your plants prior to the onset of an Arctic front, so pay attention to weather alerts. Shelter your plants from freezing wind by covering them with a tarp or bringing them into an unheated enclosure. Resume normal outdoor care when the Arctic front passes.

If you live in zones 6 or colder, areas where the temperature routinely drops below freezing for more than a week at a time, you will need to mulch your container plants for the winter. Maintain soil moisture whenever the temperature rises above freezing. Uncover your plants in early spring.

In stock March-September only.

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  • how sunlight and water affect plant growth.
  • what type of soil and pots to use.
  • if you really need to shelter your plants from snow and ice.
  • how to troubleshoot common plant problems.

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