Propagating rosemary is a rewarding and cost-effective way to produce new plants for your garden. Jason, from Fraser Valley Rose Farm, shares his tried-and-true method for taking rosemary cuttings and ensuring high success rates. This guide expands on Jason’s advice, offering insights into every step of the propagation process while addressing common questions and challenges. Whether you’re a beginner or an experienced gardener, these tips will help you grow healthy rosemary plants from cuttings.
Why Propagate Rosemary?
Rosemary is a versatile, fragrant herb that’s easy to grow and widely used in cooking and landscaping. Propagation allows gardeners to multiply their plants without spending a fortune, and it’s also a way to rejuvenate older rosemary shrubs. Jason emphasizes that even a small herb pot can yield 15–20 cuttings, making propagation both economical and practical.
Step 1: Choosing the Right Cuttings
Successful propagation starts with selecting the right type of cutting. Rosemary is a sub-shrub, meaning it combines woody and herbaceous growth. This unique growth habit requires a careful balance when taking cuttings.
- Softwood vs. Hardwood: Cuttings taken from the soft, green tips of new growth are too delicate and often fail to root. On the other hand, cuttings from the woody base of the plant take much longer to root. Jason recommends selecting semi-hardwood cuttings—firm but still pliable stems that are ideal for propagation.
- Node Selection: Nodes, the points where leaves emerge, are key to successful rooting. Aim for cuttings with at least three nodes, as these are the areas most likely to form roots.
Step 2: Preparing the Cuttings
Once you’ve selected suitable stems, preparation is straightforward:
- Trim the Cutting: Cut just below a node, ensuring the cutting is about 3–4 inches long.
- Remove Lower Leaves: Strip off leaves from the bottom two nodes to expose the area where roots will form.
- Apply Rooting Hormone: Dip the cut end into a rooting powder to encourage root growth. While optional, this step improves consistency and speeds up the process.
Step 3: Potting Mix and Setup
The potting medium plays a vital role in propagation. Jason uses a well-aerated mix of composted bark mulch and shredded wood fiber, which holds moisture while allowing air circulation. Alternative mixes, such as peat and perlite, coconut coir, or sand, also work well.
Avoid Garden Soil: Garden soil is rich in microorganisms that can cause rot in vulnerable cuttings. A clean, low-pathogen medium is essential to protect cuttings from early failure.
Fill your propagation tray with the chosen medium and insert cuttings gently, ensuring at least one node is buried in the soil.
Step 4: Creating the Right Environment
Rosemary cuttings require stable conditions to root successfully:
- Humidity: Place the tray under a humidity dome or cover it with a clear plastic bin with ventilation holes. This maintains a high-humidity environment without causing stagnation.
- Temperature: Keep the cuttings in a warm, stable location. Ideal rooting temperatures range from 21–27°C (70–80°F).
- Light: Position the tray in bright, indirect light. In fall or winter, supplement natural light with grow lights to extend daylight hours.
Step 5: Patience During Root Formation
Rooting can take several weeks, depending on the season and cutting quality. Jason notes that rosemary cuttings taken in fall may root slower than those taken in spring due to shorter days and the plant’s natural dormancy cycle.
During this time, avoid disturbing the cuttings and ensure consistent moisture levels. Overwatering can lead to rot, so allow the top layer of soil to dry slightly between waterings.
Step 6: Transplanting Rooted Cuttings
Once roots form, usually within 3–6 weeks, the cuttings are ready for transplanting. Gently remove the rooted cuttings from the tray and pot them individually into small containers with well-draining soil. Begin feeding with a dilute liquid fertilizer to support healthy root and shoot growth.
Tips for Long-Term Success
- Prune Your Parent Plant: Rosemary benefits from regular pruning to remove woody growth and encourage fresh shoots. Pruning also keeps the plant productive and reduces the risk of winter dieback.
- Prepare for Winter: In climates where rosemary is only semi-hardy, Jason advises gardeners to prune back top growth and cover the plant during cold spells. Alternatively, propagate new plants to replace older ones lost to winter damage.
Key Takeaways
- Select the Right Material: Semi-hardwood cuttings with 2–3 nodes are ideal.
- Prepare Properly: Use a clean, aerated potting mix and apply rooting hormone for the best results.
- Maintain Optimal Conditions: High humidity, warm temperatures, and consistent light are essential for rooting.
- Be Patient: Rooting can take weeks, but proper care ensures healthy new plants.
A 70% Success Rate in Propagation
Jason’s propagation method resulted in a 70% success rate for his rosemary cuttings, producing robust plants ready for spring planting. By following these steps, you can achieve similar success and enjoy a thriving rosemary garden. Whether you’re growing for culinary use, landscaping, or as a fragrant addition to your garden, propagating rosemary is an easy and rewarding project.
