Dicksonia antarctica, also known as the Tasmanian Tree Fern or Soft Tree Fern, is a stunning, prehistoric-looking fern that adds a lush, tropical feel to gardens. Here’s how to plant and care for it:
Planting Dicksonia antarctica
Choose the Right Location:
- Shade or Partial Shade: This fern prefers shade to partial shade, as direct sunlight can scorch its fronds. Ideal locations are under tree canopies or in shaded parts of the garden.
- Sheltered Spot: Choose a location that is protected from strong winds, which can damage the delicate fronds.
Soil Preparation:
- Moist, Well-Draining Soil: Dicksonia antarctica thrives in rich, organic, well-draining soil that retains moisture. You can improve soil structure by adding compost or leaf mold.
- Slightly Acidic Soil: The plant prefers slightly acidic to neutral soil (pH 5.5 - 6.5), which can be achieved by incorporating organic matter.
Planting Process:
- Dig a Generous Hole: Make a hole that is twice as wide and slightly deeper than the root ball. If planting a larger, trunked fern, dig deep enough to accommodate the trunk so that it stands securely.
- Position the Fern: Place the root ball (or trunk) into the hole. Make sure the crown (where the fronds emerge) is level with or slightly above the soil surface. For trunked ferns, plant the trunk directly in the soil, with 6-12 inches buried for stability.
- Backfill and Water Thoroughly: Fill in the hole with soil, gently pressing it around the roots or trunk to remove air pockets. Water thoroughly after planting to help the plant settle.
Caring for Dicksonia antarctica
Watering:
- Keep Soil Moist: Consistent moisture is crucial for Dicksonia antarctica, but avoid waterlogging. The soil should remain evenly moist, particularly during dry periods.
- Water the Trunk: One unique aspect of caring for this tree fern is that it absorbs water through its trunk. In dry weather, it’s important to water the trunk directly, ensuring it stays moist. This can be done by spraying it with a hose or using a drip irrigation system.
- Mist the Fronds: If the humidity is low, misting the fronds can help maintain the humidity levels around the plant, which is beneficial for its health.
Fertilizing:
- Regular Feeding: During the growing season (spring through summer), feed with a balanced, slow-release fertilizer or a liquid seaweed extract every 4-6 weeks. Use a diluted mixture to avoid over-fertilizing, which can harm the plant.
- Organic Matter: Adding compost or well-rotted manure around the base of the plant can help provide nutrients and retain moisture.
Pruning:
- Remove Dead or Damaged Fronds: Trim off any dead, yellowing, or damaged fronds to keep the plant looking tidy and healthy. Cut them close to the base of the trunk.
- Leave the Older Fronds: It’s best to leave older, healthy fronds in place, as they can help protect the crown from harsh weather and temperature changes.
Mulching:
- Maintain Moisture: Apply a thick layer of mulch around the base to retain moisture and regulate soil temperature. Mulch also adds organic matter to the soil as it decomposes, which benefits the plant.
- Avoid Covering the Trunk: Keep mulch away from direct contact with the trunk to prevent rot.
Pest Management:
- Relatively Pest-Free: Dicksonia antarctica is generally pest-resistant, but slugs and snails might occasionally feed on the fronds. Handpick them or use non-toxic slug repellents if needed.
