Fertilising guide

How to fertilise Geranium sylvaticum (Geranium sylvaticum)— schedule & NPK

Also called Wood cranesbill, Woodland geranium.

More about geranium sylvaticum

About Geranium sylvaticum

Geranium sylvaticum · also called Wood cranesbill, Woodland geranium · flowering

Wood cranesbill is a clump-forming hardy perennial from European woodland margins and damp meadows, bearing saucer-shaped violet-blue to mauve flowers with pale centres in early summer above deeply lobed leaves. It thrives in dappled shade and moist soil, flowers around May to July, dies back over winter and returns reliably each spring.

Growth habit: Clump-forming, upright herbaceous perennial that forms a mound of deeply palmate, lobed foliage topped by branching flower stems. Spreads slowly by rhizomes to make weed-suppressing colonies; dies back to the ground in winter.

What fertiliser geranium sylvaticum actually wants — and why

Geranium sylvaticum 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 geranium sylvaticum: 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 geranium sylvaticum, 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 geranium sylvaticum:

The dormant-season rule matters more than the exact interval: skip feeding entirely when geranium sylvaticum 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 geranium sylvaticum

None is the correct answer for geranium sylvaticum. 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 geranium sylvaticum first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the geranium sylvaticum watering schedule.

Signs you are over-feeding geranium sylvaticum

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

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 geranium sylvaticum

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 geranium sylvaticum care brief covers soil, humidity and the common problems for this species.

Flushing and leaching the salts

If geranium sylvaticum 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 geranium sylvaticum

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 geranium sylvaticum.

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 geranium sylvaticum — frequently asked questions

What fertiliser does geranium sylvaticum 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. Geranium sylvaticum 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 geranium sylvaticum?

Undemanding. An annual spring mulch of compost or leaf mould usually supplies enough nutrients; a single balanced general fertiliser application in spring suffices on poor soils. Avoid heavy feeding, which encourages floppy growth at the expense of flowers. Undemanding. An annual spring mulch of compost or leaf mould usually supplies enough nutrients; a single balanced general fertiliser application in spring suffices on poor soils. Avoid heavy feeding, which encourages floppy growth at the expense of flowers. In practice: no routine feeding at all for geranium sylvaticum — at most a thin compost mulch for soil structure, never a flowering or nitrogen feed.

What strength of feed for geranium sylvaticum?