Cultivating the versatile perennial herb catnip (Nepeta cataria) begins with deciding when to plant the seeds. As a member of the mint family, catnip is a robust plant known for its hardiness and ability to thrive in varied conditions. Its uses range from attracting feline friends due to its nepetalactone content to being brewed into a calming herbal tea.
Starting Catnip Seeds Indoors
Starting seeds indoors provides the earliest start to the growing process. Begin approximately six to eight weeks before the final expected frost date in your region. This allows the plant to develop a strong root system before the spring planting season. Use a sterile, fine-textured seed-starting mix in trays for the best early growth environment.
Catnip seeds require light to germinate, so sow them on the surface of the growing medium or barely cover them with soil or perlite, no deeper than 1/8 inch. Maintain a consistent soil temperature between 70°F and 75°F, often achieved with a heat mat. The soil must remain evenly moist but never saturated. Once seedlings have several sets of true leaves and outdoor temperatures are reliably warm, they require “hardening off.” This involves gradually acclimating the young plants to outdoor conditions, such as wind and direct sun, for about a week before transplanting.
Direct Sowing Catnip Seeds Outdoors
Catnip can also be planted directly into the garden soil, which is less labor-intensive but requires warmer weather. Direct sowing should occur only after all danger of frost has passed and the soil has warmed considerably. For best germination, the soil temperature should register between 65°F and 75°F.
Preparing the outdoor seedbed involves loosening the top few inches of soil and ensuring it is free of debris or weeds. Plant the seeds very shallowly, pressing them lightly onto the soil surface, as they need light exposure to sprout. Covering the seeded area with a light layer of fine compost or sand helps prevent the seeds from washing away during watering. This method is often performed in early spring or mid-summer, though newly sown seeds must be protected from neighborhood cats.
Essential Steps for Successful Germination and Growth
Catnip requires between 7 and 21 days to sprout, depending heavily on consistent warmth and moisture. Once seedlings emerge, they require a location that receives full sun, which promotes the highest oil concentration and strongest aroma in the foliage. Although full sun is best, the plant is adaptable and tolerates areas that receive partial shade.
Catnip thrives in average, well-draining soil and does not require rich earth, often growing vigorously even in poor or sandy conditions. Overly wet soil is detrimental to the plant’s health and must be avoided. When seedlings reach a few inches in height, thin them out to ensure proper air circulation and resource availability, leaving 12 to 18 inches between each plant.
After the plants are established, their maintenance needs are minimal, demonstrating resilience to dry conditions. Water only once the top few inches of soil have dried out completely. Pinching back the growing tips of young plants encourages a bushier, more compact growth habit. Once established, catnip requires little intervention, providing a steady supply of fragrant leaves.