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Fertilising guide

How to fertilise Persian Catmint (Nepeta mussinii)— schedule & NPK

Also called Persian Catmint, Mussini Catmint.

More about persian catmint

About Persian Catmint

Nepeta mussinii · also called Persian Catmint, Mussini Catmint · flowering

Persian Catmint is a compact, low-growing species native to the Caucasus and Iran, producing dense spikes of small violet-blue flowers above soft, silvery-green aromatic foliage. It is an excellent front-of-border or edging plant, highly attractive to bees and pollinators. Drought-tolerant and easy to grow in well-drained sunny positions.

Growth habit: Low-mounding, spreading herbaceous perennial

What fertiliser persian catmint actually wants — and why

Persian Catmint is an easy, light foliage feeder — a half-strength balanced liquid feed through the growing months keeps it green without forcing weak, sappy growth.

A balanced general houseplant feed (roughly even N-P-K) is exactly right — it is grown for foliage, so steady, moderate nitrogen for healthy leaves is the goal, not a bloom or root formula.

For the language behind the three numbers on the bottle — what nitrogen, phosphorus and potassium each do — see the NPK ratio explained entry. The short version for persian catmint: match the feed to the job the plant is doing right now, not to a generic “plant food” on the shelf.

How often to feed persian catmint, and which months

Feeding only earns its keep while the plant is in active growth and can use the nutrients — pour feed into a dormant or low-light plant and it simply builds up as root-burning salt. For persian catmint:

Apply a light balanced feed in spring only if the soil is very poor. Excessive fertility leads to lax growth. This species thrives in lean, unfertilised conditions typical of its native range. Treat that as sparingly through the growing season between spring through early autumn (roughly March to September); ease off in autumn and stop entirely in the low light of winter.

The dormant-season rule matters more than the exact interval: skip feeding entirely when persian catmint is resting. For the wider context on indoor feeding rhythms across the seasons, the houseplant fertiliser schedule walks through the year month by month.

What strength to mix for persian catmint

Half strength is the safe default for persian catmint — houseplant feeds are formulated strong, and the diluted dose is gentler on the roots while still ample for foliage.

Feeding always goes onto already-damp soil, never dry roots — water persian catmint first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the persian catmint watering schedule.

Signs you are over-feeding persian catmint

Over-feeding is far more common — and more damaging — than under-feeding for most plants. The classic tells for persian catmint:

Signs you are under-feeding persian catmint

If the symptoms point at watering, light or roots rather than nutrition, the full persian catmint care brief covers soil, humidity and the common problems for this species.

Flushing and leaching the salts

Flush the pot of persian catmint with plain water until it runs freely from the base every couple of months in the feeding season — it washes out the fertiliser salts that cause brown tips.

Organic vs synthetic feeds for persian catmint

Organic options

A diluted seaweed or worm-casting feed, or fish emulsion if you can tolerate the smell indoors. UK: Westland or Baby Bio Organic, dilute seaweed; US: Espoma Indoor! or Neptune's Harvest fish & seaweed. Slow, gentle and hard to overdo.

Synthetic / liquid feeds

A general-purpose houseplant liquid at half strength — UK: Baby Bio, Westland Houseplant Feed or Phostrogen; US: Miracle-Gro Indoor Plant Food or Schultz. Convenient and fast-acting; the only risk is overdoing it.

Brand names are examples, not endorsements, and UK and US ranges differ — check the label’s own NPK and dilution rate, since formulations change.

Fertilising persian catmint — frequently asked questions

What fertiliser does persian catmint need?

A balanced general houseplant feed (roughly even N-P-K) is exactly right — it is grown for foliage, so steady, moderate nitrogen for healthy leaves is the goal, not a bloom or root formula. Persian Catmint is an easy, light foliage feeder — a half-strength balanced liquid feed through the growing months keeps it green without forcing weak, sappy growth.

How often should I feed persian catmint?

Apply a light balanced feed in spring only if the soil is very poor. Excessive fertility leads to lax growth. This species thrives in lean, unfertilised conditions typical of its native range. Apply a light balanced feed in spring only if the soil is very poor. Excessive fertility leads to lax growth. This species thrives in lean, unfertilised conditions typical of its native range. Treat that as sparingly through the growing season between spring through early autumn (roughly March to September); ease off in autumn and stop entirely in the low light of winter.

What strength of feed for persian catmint?

Half strength is the safe default for persian catmint — houseplant feeds are formulated strong, and the diluted dose is gentler on the roots while still ample for foliage.

What does over-feeding persian catmint look like?

Brown, crispy leaf tips and edges with no sign of underwatering. A white, crusty salt deposit on the soil surface or pot rim. Weak, pale, stretched new growth that flops. Lower leaves yellow and drop while the soil is correctly watered. Feeding persian catmint year-round on a fixed schedule, including dark winter months, is the most common mistake — it cannot use the nutrients in low light and the surplus simply burns the roots and crusts the soil.

Should I flush the soil of persian catmint?

Flush the pot of persian catmint with plain water until it runs freely from the base every couple of months in the feeding season — it washes out the fertiliser salts that cause brown tips.

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