Propagation of Jacob’s Ladder (Polemonium caeruleum) can be done through three different methods: cuttings, division, or seeds. Each method has its own advantages and may be suitable depending on the specific situation.
1. Softwood tip cuttings: This method is best done in the spring months when the plant is actively growing. Select young shoots that are still soft and not yet woody. Cuttings should be around 4-6 inches long and taken from the tips of the plant. Remove the lower leaves from the cutting and dip the cut end in rooting hormone powder to encourage root development. Place the cuttings in a well-draining potting mix, keeping them moist but not waterlogged. Provide them with indirect light and maintain a warm temperature. Within a few weeks, roots should start to develop, and the cutting can be transplanted into a larger container or directly into the garden.
2. Division: Established clumps of Jacob’s Ladder can be divided every 3-4 years to maintain plant health and vigor. This is typically done in early spring or early fall when the plant is dormant. Dig up the entire clump and carefully separate the plant into smaller sections, ensuring each section has a good amount of roots and foliage. Replant the divisions at the same depth as they were originally growing, spacing them apart according to their mature size. Water thoroughly after replanting and continue to provide regular care until they become established.
3. Seeds: Jacob’s Ladder can also be propagated from seeds. This method is best done in late fall or early spring. Prepare the soil by removing any weeds and loosening it with a garden fork or tiller. Sow the seeds directly into the garden, scattering them over the prepared soil and lightly covering them with a thin layer of soil or compost. Water gently to settle the seeds in place. In the spring, as the weather warms, the seeds will germinate and begin to grow. Thin out the seedlings when they are large enough to handle, allowing enough space for each plant to grow and develop. Keep the soil consistently moist during the germination and early growth stages.
It’s worth noting that Jacob’s Ladder may also self-seed in the garden, producing new plants without any intervention. These self-seeded plants can be transplanted or left to grow where they appear, depending on personal preference.
In my personal experience, I have successfully propagated Jacob’s Ladder through softwood cuttings and division. Both methods have yielded healthy and thriving plants. I find the softwood cuttings to be particularly rewarding as I can quickly create new plants from the parent plant and have them ready for planting within a few weeks. Division is also a great way to rejuvenate an established clump and maintain its vigor over time. Jacob’s Ladder is a relatively easy plant to propagate, and experimenting with different methods can be a fun and rewarding gardening experience.