Updated: July 18, 2023

Lehmann’s plant (Phlomis fruticosa), also known as Jerusalem sage, is a beautiful and versatile perennial that can add vibrant color and texture to any garden. Native to the Mediterranean region, this plant features attractive silver-gray foliage and produces stunning yellow flowers in the summer months. If you’re a fan of Lehmann’s plant and want to multiply your collection, propagating it is a great way to do so. In this article, we will guide you through the process of propagating Lehmann’s plant successfully.

Understanding Lehmann’s Plant Propagation

Before we delve into the specific propagation techniques, it’s essential to understand the two main methods used for propagating Lehmann’s plant: seeds and stem cuttings.

Seeds: Propagating Lehmann’s plant from seeds is relatively straightforward. However, it may take longer for the new plants to establish themselves and start flowering.

Stem Cuttings: This method involves taking a healthy stem from an existing Lehmann’s plant and encouraging it to develop roots. Stem cuttings generally root faster than seeds and can result in identical genetic clones of the parent plant.

Now that we have an overview let’s dive into the step-by-step process for each method:

Propagating Lehmann’s Plant from Seeds

  1. Collecting Seeds: Wait until the flowers have faded, and the seed heads have formed. Collect these seed heads by cutting them from the plant using sharp, clean scissors or shears.

  2. Preparing the Seeds: Place the seed heads in a paper bag or envelope and allow them to dry for several weeks. Once dry, gently rub the seed heads between your hands to release the seeds.

  3. Sowing Seeds: Fill small pots or seed trays with well-draining potting soil or a seed-starting mix. Sprinkle the seeds evenly over the soil surface and cover them with a thin layer of soil. Mist the soil lightly to moisten it.

  4. Germination and Care: Place the pots or trays in a warm, bright location, such as a sunny windowsill. Keep the soil consistently moist but not waterlogged. Germination typically occurs within two to four weeks. Once the seedlings develop their second set of true leaves, you can transplant them into individual pots or directly into the garden.

Propagating Lehmann’s Plant from Stem Cuttings

  1. Selecting Cuttings: Choose a healthy, non-flowering stem from an established Lehmann’s plant. The stem should be approximately 4-6 inches long and have at least three sets of leaves.

  2. Preparing the Cuttings: Using sharp, sterilized pruning shears, make a clean cut just below a node (the point where a leaf is attached to the stem). Remove any leaves from the lower half of the cutting, leaving only a few leaves at the top.

  3. Rooting Hormone (Optional): While not necessary, applying a rooting hormone powder or gel to the cut end of the stem can encourage faster root development.

  4. Planting Cuttings: Fill a small pot or container with well-draining potting soil or a propagation mix. Make a hole in the soil using a pencil or your finger and insert the cutting into it, ensuring that at least one node is below the soil surface.

  5. Rooting Process: Place the pot in a warm area with bright, indirect light. Mist the cutting and soil lightly to maintain moisture levels without overwatering. You can cover the pot with a plastic bag or place it in a propagator to create a humid environment that aids rooting.

  6. Transplanting: After several weeks, gently tug on the stem to check for resistance, indicating root development. Once roots have formed, transplant the cutting into a larger pot or directly into the garden, ensuring it receives adequate sunlight and water.

Caring for Newly Propagated Lehmann’s Plants

Whether you’ve propagated Lehmann’s plant from seeds or stem cuttings, it’s essential to provide proper care to ensure the success of your new plants:

  • Watering: Water newly propagated plants regularly to keep the soil consistently moist but not soggy. As they establish themselves, gradually reduce watering frequency.

  • Sunlight: Place your Lehmann’s plants in a location that receives full sun or partial shade, depending on your local climate. Provide at least six hours of direct sunlight daily for optimal growth and flowering.

  • Fertilization: Apply a balanced, slow-release fertilizer once a month during the growing season to provide essential nutrients. Follow the package instructions for appropriate dosage.

  • Pruning: Regularly remove dead or damaged foliage from your Lehmann’s plants to promote healthy growth. Pruning can be done in late winter or early spring before new growth emerges.

By following these propagation techniques and caring for your newly propagated Lehmann’s plants, you can successfully expand your collection and enjoy their beauty throughout your garden.

Remember, patience is key when propagating plants. Don’t get discouraged if you don’t see immediate results. With time and proper care, you’ll soon have a thriving collection of Lehmann’s plants to admire and share with others.