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Fertilising guide

How to fertilise Crosswort (Cruciata laevipes)— schedule & NPK

Also called Crosswort, Smooth Bedstraw.

More about crosswort

About Crosswort

Cruciata laevipes · also called Crosswort, Smooth Bedstraw · flowering

Crosswort (Cruciata laevipes, syn. Galium cruciata) is a low-growing native perennial of the Rubiaceae family, widespread across the UK in woodland edges, hedgerows, and calcareous grassland. Its whorls of four hairy, cross-shaped leaves give the plant its name, and tiny pale yellow honey-scented flowers appear from April to June. The most important care point is that it needs moderately fertile, well-drained, neutral to calcareous soil and will spread by rhizomes to form loose ground-covering mats. No records of toxicity to cats or dogs exist; it is considered of low concern but not formally listed as pet-safe by ASPCA.

Growth habit: Low, sprawling perennial forming spreading mats via rhizomes; stems to 60 cm, softly hairy, with whorls of four leaves.

What fertiliser crosswort actually wants — and why

Crosswort 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 crosswort: 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 crosswort, 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 crosswort:

No feeding required; grow in moderately fertile soil without supplemental fertiliser to avoid rank growth that suppresses flowering. 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 crosswort 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 crosswort

Half strength is the safe default for crosswort — 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 crosswort first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the crosswort watering schedule.

Signs you are over-feeding crosswort

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

Signs you are under-feeding crosswort

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

Flushing and leaching the salts

Flush the pot of crosswort 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 crosswort

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 crosswort — frequently asked questions

What fertiliser does crosswort 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. Crosswort 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 crosswort?

No feeding required; grow in moderately fertile soil without supplemental fertiliser to avoid rank growth that suppresses flowering. No feeding required; grow in moderately fertile soil without supplemental fertiliser to avoid rank growth that suppresses flowering. 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 crosswort?

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

What does over-feeding crosswort 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 crosswort 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 crosswort?

Flush the pot of crosswort 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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