How to Grow Catmint (Short-stemmed)
Grow Guide #2628
Binomial name: Nepeta subsessilis
Life Cycle: Perennial
This 'How to Grow' guide details everything a home gardener needs to know to plant, grow and care for Short-stemmed catmint (Nepeta subsessilis).
When to Sow Short-stemmed catmint Seeds
Short-stemmed catmint is a perennial plant that grows year round in most climates. Use the table below to identify the best time of year to sow short-stemmed catmint seeds in your climate.
Short-stemmed catmint plants are best grown in full sun or part shade. Choose a location that will receive at least 3 hours of full sun each day.
Short-stemmed catmint plants are perennial, meaning they live for several years. Choose a permanent position where plants can grow undisturbed by regular digging or other disturbance.
Short-stemmed catmint plants need a well drained soil enriched with plenty of organic matter. Prepare soil by weeding it thoroughly, digging it over to loosen it and adding aged animal manure or compost. Keep the area free of weeds until planting. Learn more about preparing soil for planting here.
Short-stemmed catmint plants can be grown in containers. If possible choose a variety that’s recommended for container growing. Use a good quality potting mix and make sure your container is large enough for mature plants; a minimum of 10 litres is recommended for short-stemmed catmint. During the growing season, keep in mind that container grown plants may need additional fertiliser to encourage healthy growth.
How to Sow Short-stemmed catmint Seeds
Short-stemmed catmint seeds do not require any treatment (eg soaking, stratification) before sowing.
Short-stemmed catmint seeds grow best when they are raised in trays or other containers and transplanted to the garden once established.
- Fill trays, punnets or jiffy pots with a good quality seed-raising mix, or use soil starter pellets.
- Sow seeds 10mm deep.
- Keep soil moist but never wet or dry.
- Seeds should germinate in around 10-20 days at a soil temperature of 21-27°C.
- Transplant seedlings to the garden once they have their first true leaves and are large enough to handle (usually 5-10cm tall).
- Plant out, spacing plants 60cm apart.
Optional: In cool climates short-stemmed catmint seeds can be sown indoors 6 weeks before the last expected frost. Grow them in a warm position with plenty of natural light.
How to Grow Short-stemmed catmint
Short-stemmed catmint plants need regular watering during the growing season. Do not let soil dry out; keep soil evenly moist but not waterlogged. Water deeply in the early morning or late afternoon. Avoid watering the leaves of plants to avoid fungal diseases. Learn more about watering here.
If soil was well prepared no extra fertiliser should be necessary. In poor soil or to give your plants an extra boost, application of a high-potassium fertiliser or one formulated for flowering plants can be beneficial:
- Apply slow release fertiliser at the recommended rate when transplanting or when seedlings are 5-10cm tall.
- Apply liquid fertiliser at the recommended rate and frequency while plants are fruiting or flowering.
Short-stemmed catmint plants should flower in approximately 105 days.
Deadhead short-stemmed catmint flowers regularly during the growing season. Using sharp secateurs or snips cut fading or dead flowers off just above a set of leaves. Removing old flowers regularly will encourage plants to produce more flowers. Learn more about deadheading flowering plants here.
When plants have finished flowering prune them back to neaten them and encourage strong new growth. Using sharp secateurs or snips, cut individual stems just above a set of lower leaves.
Common Problems when Growing Short-stemmed catmint
Like all plants, short-stemmed catmint is susceptible to some pests, diseases and other problems. Below is a list of the most common problems gardeners encounter when growing short-stemmed catmint plants:
- Aphids are small (2-4mm long) sap-sucking insects that congregate on the new shoots or the undersides of leaves. They can cause leaves to wilt or become discoloured, and also excrete honeydew which can attract ants and other insect pests. To manage aphids, remove them by spraying with a garden hose, apply a soap or alcohol spray, or encourage predatory insects to your garden. Read more about aphids here.
- Slugs and snails are molluscs that feed on tender leaves and shoots, mostly at night, leaving slimy trails behind them. Control them by removing their hiding places, keeping free range poultry, collecting them by torchlight or by placing traps. Read more about slugs and snails here.
- Whitefly is a sap-sucking insect related to aphids. They are often found in large numbers on the underside of leaves and will swarm in clouds when disturbed. Plants may have yellowing leaves or may wilt, and growth will be slowed. Whitefly can be removed with a garden hose or sprayed with soap spray. Badly affected plants should be destroyed. Attracting beneficial insects that will prey on whitefly can be beneficial. Read more about managing whitefly here.