Fertilising guide
How to fertilise Woolly Lavender (Lavandula lanata)— schedule & NPK
Also called Woolly lavender, White-woolly lavender.
More about woolly lavender
About Woolly Lavender
Lavandula lanata · also called Woolly lavender, White-woolly lavender · herb
A distinctive Spanish mountain lavender with conspicuously white-woolly stems and broad silver-white leaves that give the plant a striking textural appearance unlike any other lavender. It produces long, slender spikes of deep violet-purple, strongly fragrant flowers in summer and is moderately cold-hardy for a Mediterranean species. Sharp drainage and full sun are non-negotiable; this species comes from high-altitude, dry limestone habitats in southern Spain. Lavender is toxic to cats, dogs, and horses according to the ASPCA.
Growth habit: Compact, upright, evergreen dwarf shrub with distinctively broad, white-felted leaves and tall, slender flowering spikes.
What fertiliser woolly lavender actually wants — and why
Woolly Lavender is a soft, fast leafy herb that you harvest hard — a modest balanced feed keeps tender growth coming without tipping it into bland or bolting.
A balanced general feed (even N-P-K) at modest strength — enough nitrogen to keep replacing the leaves you pick, but not so much that flavour thins or it bolts to seed.
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 woolly lavender: 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 woolly lavender, 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 woolly lavender:
Feed very sparingly or not at all; a single light application of slow-release, low-nitrogen granules in early spring is sufficient. Rich feeding ruins plant habit and reduces hardiness. In practice: a balanced liquid feed every few weeks through the main growing and harvesting season (spring through early autumn), more often the harder you are picking it.
The dormant-season rule matters more than the exact interval: skip feeding entirely when woolly lavender 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 woolly lavender
Half strength is a sensible default for woolly lavender — enough to fuel regrowth after cutting, gentle enough that the leaves stay aromatic rather than watery.
Feeding always goes onto already-damp soil, never dry roots — water woolly lavender first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the woolly lavender watering schedule.
Signs you are over-feeding woolly lavender
Over-feeding is far more common — and more damaging — than under-feeding for most plants. The classic tells for woolly lavender:
- Fast, soft, pale growth with diluted, less aromatic flavour.
- Early bolting (running to flower) and a bitter edge.
- Salt crust and scorched tips on container plants.
Signs you are under-feeding woolly lavender
- Pale, slow regrowth after cutting and small leaves.
- A tired, stalled plant that cannot keep up with harvesting.
- Yellowing older leaves in a long-spent pot.
If the symptoms point at watering, light or roots rather than nutrition, the full woolly lavender care brief covers soil, humidity and the common problems for this species.
Flushing and leaching the salts
Pot-grown woolly lavender builds up feed salts quickly — water until it drains each time and flush the pot with plain water every few weeks, especially on a sunny windowsill.
Organic vs synthetic feeds for woolly lavender
Organic options
A diluted seaweed feed or worm-casting tea keeps soft growth coming without overdoing it. UK: dilute seaweed or Westland; US: Espoma Garden-tone or Neptune's Harvest. Gentle, hard to overdo, flavour-friendly.
Synthetic / liquid feeds
A balanced liquid feed at half strength through harvesting — UK: Phostrogen, Baby Bio or Westland; US: Miracle-Gro all-purpose at half strength. Fast regrowth; just do not overdo the nitrogen.
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 woolly lavender — frequently asked questions
What fertiliser does woolly lavender need?
A balanced general feed (even N-P-K) at modest strength — enough nitrogen to keep replacing the leaves you pick, but not so much that flavour thins or it bolts to seed. Woolly Lavender is a soft, fast leafy herb that you harvest hard — a modest balanced feed keeps tender growth coming without tipping it into bland or bolting.
How often should I feed woolly lavender?
Feed very sparingly or not at all; a single light application of slow-release, low-nitrogen granules in early spring is sufficient. Rich feeding ruins plant habit and reduces hardiness. Feed very sparingly or not at all; a single light application of slow-release, low-nitrogen granules in early spring is sufficient. Rich feeding ruins plant habit and reduces hardiness. In practice: a balanced liquid feed every few weeks through the main growing and harvesting season (spring through early autumn), more often the harder you are picking it.
What strength of feed for woolly lavender?
Half strength is a sensible default for woolly lavender — enough to fuel regrowth after cutting, gentle enough that the leaves stay aromatic rather than watery.
What does over-feeding woolly lavender look like?
Fast, soft, pale growth with diluted, less aromatic flavour. Early bolting (running to flower) and a bitter edge. Salt crust and scorched tips on container plants. Over-feeding woolly lavender with strong nitrogen is the usual mistake — it grows fast and lush but the leaves turn bland and it bolts to flower sooner, ending the useful harvest early.
Should I flush the soil of woolly lavender?
Pot-grown woolly lavender builds up feed salts quickly — water until it drains each time and flush the pot with plain water every few weeks, especially on a sunny windowsill.
Keep reading
- Woolly Lavender care — the full brief (light, soil, humidity, problems, pet safety)
- How often to water woolly lavender — the watering schedule
- The houseplant fertiliser schedule — feeding through the year
- NPK ratio explained — what the three numbers on the bottle mean
- How to fertilise golden oregano
- How to fertilise cuban oregano
- How to fertilise purple sage
- All 10153 fertilising guides in the Growli library