Fertilising guide

How to fertilise Wallich's Cranesbill (Geranium wallichianum)— schedule & NPK

Also called Wallich's cranesbill, Wallich geranium.

More about wallich's cranesbill

About Wallich's Cranesbill

Geranium wallichianum · also called Wallich's cranesbill, Wallich geranium · flowering

Geranium wallichianum is a scrambling, trailing hardy perennial from the Himalayas and Afghanistan, bearing large saucer-shaped flowers — typically violet-blue to magenta with a contrasting white eye — from midsummer right through to the first frosts. Unlike upright clump-forming cranesbills, it sprawls across neighbouring plants and the ground, making it excellent for weaving through shrubs or spilling over banks. The famous cultivar 'Buxton's Variety' carries rich blue flowers whose colour fades to pink in summer heat and returns to blue in cooler weather. Considered non-toxic to cats and dogs.

Growth habit: Scrambling, trailing herbaceous perennial

What fertiliser wallich's cranesbill actually wants — and why

Wallich's Cranesbill flowers best on poor soil — feed it and you get a lush leafy plant with very few blooms, the exact opposite of what you want.

Little or nothing. Rich, especially nitrogen-rich, soil pushes foliage at the expense of flowers in this plant — lean ground is the technique, not a deficiency.

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 wallich's cranesbill: 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 wallich's cranesbill, 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 wallich's cranesbill:

A single application of balanced slow-release fertiliser in spring is sufficient; over-feeding promotes lush foliage at the expense of flowers. In practice: no routine feeding at all for wallich's cranesbill — at most a thin compost mulch for soil structure, never a flowering or nitrogen feed.

The dormant-season rule matters more than the exact interval: skip feeding entirely when wallich's cranesbill 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 wallich's cranesbill

None is the correct answer for wallich's cranesbill. The flower-versus-foliage trade-off is the whole point: hold back and you get the display.

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

Signs you are over-feeding wallich's cranesbill

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

Abundant leafy growth and very few flowers (the classic over-rich symptom).
Soft, floppy stems and a sprawling, leafy habit.
Scorched edges and salt crust if it has been fed in a container.

Signs you are under-feeding wallich's cranesbill

Effectively never an issue — these plants flower on poverty.
Only on genuinely dead soil: weak, thin growth and few blooms.
A short-lived plant in completely spent container compost.

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

Flushing and leaching the salts

If wallich's cranesbill has accidentally been fed and is all leaf, a plain-water flush plus a move to leaner soil resets it; otherwise no flushing is needed because you are not feeding it.

Organic vs synthetic feeds for wallich's cranesbill

Organic options

A thin compost mulch for soil structure is the absolute most; mostly, give it nothing. UK/US: leave it lean — no manure, no liquid feed. Poor soil is the active ingredient here.

Synthetic / liquid feeds

None. Synthetic feeds, particularly anything with appreciable nitrogen, directly suppress flowering in wallich's cranesbill.

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 wallich's cranesbill — frequently asked questions

What fertiliser does wallich's cranesbill need?

Little or nothing. Rich, especially nitrogen-rich, soil pushes foliage at the expense of flowers in this plant — lean ground is the technique, not a deficiency. Wallich's Cranesbill flowers best on poor soil — feed it and you get a lush leafy plant with very few blooms, the exact opposite of what you want.

How often should I feed wallich's cranesbill?

A single application of balanced slow-release fertiliser in spring is sufficient; over-feeding promotes lush foliage at the expense of flowers. A single application of balanced slow-release fertiliser in spring is sufficient; over-feeding promotes lush foliage at the expense of flowers. In practice: no routine feeding at all for wallich's cranesbill — at most a thin compost mulch for soil structure, never a flowering or nitrogen feed.

What strength of feed for wallich's cranesbill?