Growing Catnip Indoors: Pot Size, Thinning, and Care

Catnip (Nepeta cataria) is a vigorous perennial that prefers outdoors, but can be grown inside with effort.

Seed Starting & Thinning

• Sow on moist sterile mix, press lightly, cover 1/8".
• Bottom heat (70°F) speeds germination (7–14 days).
• At 2–3" tall, thin to 3 strongest seedlings per 10–18" pot.

Indoor Requirements

• Light: 6+ hours direct sun (south window) OR 16h grow lights.
• Pot: 12"+ deep, wide. Drainage essential.
• Soil: Compost-rich, well-drained.
• Water: Moist, not soggy. Allow surface dry.
• Feed: Liquid fish fertilizer every 3 weeks.
• Airflow: Fan on low prevents fungal issues.
• Prune: Cut 1/3 from tips every 3 weeks for bushiness.

Outdoor Advantage

Catnip thrives outdoors: huge plants, self-seeds, returns yearly, deters rodents. If possible, move pots outside spring–fall. Bring in before hard freeze.

Medicinal Note

Traditionally used for menstrual discomfort (tea, 1 tsp dried/cup, week before cycle). Consult herbalist for personal use.

Mice/rats avoid catnip—bonus for indoor growers!