Catmint (Nepeta) is a popular perennial herb. It is cherished for its attractive, often gray-green, aromatic foliage and lavender-blue flowers that bloom for an extended period. It attracts pollinators like bees and butterflies, is deer resistant, and enhances garden aesthetics. Propagation allows gardeners to expand plantings, share with others, or replace older plants.
When to Propagate Catmint
Timing is important for successful catmint propagation. For cuttings, early summer is ideal, as the plant is actively growing, producing fresh, pliable stems that root easily. Division is best performed in spring or early autumn when temperatures are moderate, reducing transplant stress. Sowing seeds indoors occurs in early spring, six to eight weeks before the last expected frost, to give seedlings a head start. For direct outdoor sowing, wait until after the last frost to ensure optimal germination conditions.
Propagating Catmint from Cuttings
Selecting and Taking Cuttings
Select healthy, non-flowering stems that are actively growing. These stems should be pliable enough to snap when bent. Using sharp, clean pruners or a knife, take cuttings that are about 4 to 6 inches long, making the cut just below a leaf node, where roots will form. Take cuttings in the morning when the plant is well-hydrated.
Preparing Cuttings for Planting
Remove the leaves from the lower half to two-thirds of each stem, to prevent foliage submersion. This prevents rot and directs energy towards root development. Dipping the cut end into rooting hormone powder can encourage faster root formation. Prepare a well-draining rooting medium like perlite, sand, or seed-starting soil.
Planting and Rooting Cuttings
Create small holes in the prepared rooting medium, then insert each cutting about 1 inch deep. Gently firm the medium around the stem. Water the cuttings thoroughly, keeping the medium consistently moist. Placing the pot in a location with bright, indirect light and creating a humid environment will aid rooting. Roots develop within two to three weeks, indicated by new top growth or slight resistance.
Propagating Catmint by Division
Preparing for Division
Division is an effective method for rejuvenating overgrown catmint plants every three to four years. Identify a mature plant that shows signs of reduced flowering or is too large. Have a sharp spade or sturdy knife ready to separate the root ball.
Dividing the Plant
Carefully dig around the entire catmint clump, lifting it from the ground, keeping the root ball intact. Gently shake off excess soil. Use your hands or a sharp tool to divide the plant into smaller sections, ensuring each new section has roots and several shoots. For very large clumps, use a sharp spade to slice through the root ball.
Replanting Divisions
Prepare the new planting sites by loosening the soil and amending it with compost for drainage and fertility. Plant each division at the same depth it was originally growing. Backfill with soil, gently firming it around the roots. Water the newly planted divisions thoroughly immediately after replanting to settle the soil and reduce transplant shock. Consistent watering is important during establishment.
Propagating Catmint from Seeds
Sowing Catmint Seeds Indoors
Sowing seeds indoors allows for earlier blooms. Begin six to eight weeks before the last spring frost, using a seed-starting mix in trays or small pots. Catmint seeds require light for germination, so press them lightly onto the soil surface. Maintain consistent moisture by misting, and place the trays in a warm spot, ideally between 65-70°F (18-21°C), with indirect light. Germination occurs within 7 to 20 days.
Sowing Catmint Seeds Outdoors
Direct sowing outdoors is an option once frost danger has passed and soil temperatures are suitable. Prepare the garden bed by weeding and loosening the soil, adding compost. Scatter the seeds thinly on the soil surface, lightly pressing them in. Ensure the soil remains consistently moist through germination. Once seedlings are established and have a few true leaves, thin them to their recommended spacing, 12 to 18 inches apart.
Caring for Newly Propagated Catmint
Newly propagated catmint plants require attentive care. Consistent watering is important, but avoid overwatering to prevent root rot. Allow soil to dry slightly between waterings. For plants started indoors or from cuttings, gradually acclimate them to outdoor conditions over a week or two before transplanting, a process known as hardening off. Provide new plants with a location that receives full sun to partial shade. Protecting young plants from extreme weather or pests helps ensure their success.