Fertilising guide
How to fertilise Lavandin (Lavandula × intermedia)— schedule & NPK
Also called lavandin, Dutch lavender, hybrid lavender.
More about lavandin
About Lavandin
Lavandula × intermedia · also called lavandin, Dutch lavender · herb
Lavandin is a vigorous sterile hybrid of English and spike lavender, grown for its long, camphor-scented flower spikes and abundant essential oil. A woody Mediterranean sub-shrub, it demands full sun and sharp drainage, tolerates drought and poor soil, and resents wet, heavy ground. Larger and later-flowering than English lavender.
Growth habit: Rounded, woody evergreen sub-shrub forming a dense mound of grey-green foliage, with long aromatic flower spikes held well above the leaves in mid- to late summer.
Watch for — Poor flowering in shade or rich soil: Too little sun or over-feeding yields lush foliage but few spikes. Give full sun and lean soil, and hold back on nitrogen.
What fertiliser lavandin actually wants — and why
Lavandin is a lean, aromatic herb — the essential-oil flavour you grow it for is strongest in poor soil, so feeding it actively makes it worse.
Little or nothing. If anything, a very weak balanced feed or a thin compost top-dress — never a rich nitrogen feed, which dilutes the aromatic oils and produces soft, bland, floppy growth.
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 lavandin: 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 lavandin, 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 lavandin:
Very light feeder. Avoid rich feeding, which produces soft, floppy growth and fewer flowers. A light dressing of compost or a low dose of balanced fertilizer in spring is ample; lean conditions concentrate the fragrance. In practice: a spring compost top-dress at most, and otherwise leave lavandin unfed — lean, sharp-draining soil is exactly what concentrates its flavour.
The dormant-season rule matters more than the exact interval: skip feeding entirely when lavandin 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 lavandin
As weak as it gets for lavandin, or none at all. The flavour-versus-growth trade-off runs the opposite way to leafy crops: restraint is the technique.
Feeding always goes onto already-damp soil, never dry roots — water lavandin first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the lavandin watering schedule.
Signs you are over-feeding lavandin
Over-feeding is far more common — and more damaging — than under-feeding for most plants. The classic tells for lavandin:
- Lush, soft, fast growth with noticeably weaker scent and flavour.
- Floppy stems, sparse essential oils, and poor cold/wet hardiness.
- Salt crust in containers and scorched leaf tips from over-feeding.
Signs you are under-feeding lavandin
- Rare — these herbs thrive on lean soil.
- Only on truly exhausted soil: pale, thin, very slow growth.
- A short-lived, weak plant in a long-spent container.
If the symptoms point at watering, light or roots rather than nutrition, the full lavandin care brief covers soil, humidity and the common problems for this species.
Flushing and leaching the salts
Over-feeding is so unlikely with lavandin that flushing is rarely needed; if a container has had feed, a single plain-water flush and a switch to a leaner, grittier mix resets it.
Organic vs synthetic feeds for lavandin
Organic options
A thin spring mulch of garden compost or leaf-mould is the most these want. UK: a little garden compost; US: a light Espoma Garden-tone top-dress at most. Lean and gritty beats fed and rich every time.
Synthetic / liquid feeds
Generally none for lavandin. At absolute most, a very dilute balanced feed once or twice in a container; in the ground, nothing — synthetic feeds work directly against the flavour.
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 lavandin — frequently asked questions
What fertiliser does lavandin need?
Little or nothing. If anything, a very weak balanced feed or a thin compost top-dress — never a rich nitrogen feed, which dilutes the aromatic oils and produces soft, bland, floppy growth. Lavandin is a lean, aromatic herb — the essential-oil flavour you grow it for is strongest in poor soil, so feeding it actively makes it worse.
How often should I feed lavandin?
Very light feeder. Avoid rich feeding, which produces soft, floppy growth and fewer flowers. A light dressing of compost or a low dose of balanced fertilizer in spring is ample; lean conditions concentrate the fragrance. Very light feeder. Avoid rich feeding, which produces soft, floppy growth and fewer flowers. A light dressing of compost or a low dose of balanced fertilizer in spring is ample; lean conditions concentrate the fragrance. In practice: a spring compost top-dress at most, and otherwise leave lavandin unfed — lean, sharp-draining soil is exactly what concentrates its flavour.
What strength of feed for lavandin?
As weak as it gets for lavandin, or none at all. The flavour-versus-growth trade-off runs the opposite way to leafy crops: restraint is the technique.
What does over-feeding lavandin look like?
Lush, soft, fast growth with noticeably weaker scent and flavour. Floppy stems, sparse essential oils, and poor cold/wet hardiness. Salt crust in containers and scorched leaf tips from over-feeding. Feeding lavandin like a leafy vegetable is the defining mistake — rich nitrogen gives you a big, soft, fast plant whose leaves are watery and bland, with weak winter-rot resistance.
Should I flush the soil of lavandin?
Over-feeding is so unlikely with lavandin that flushing is rarely needed; if a container has had feed, a single plain-water flush and a switch to a leaner, grittier mix resets it.
Keep reading
- Lavandin care — the full brief (light, soil, humidity, problems, pet safety)
- How often to water lavandin — 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 basil
- How to fertilise herb garden
- How to fertilise mint
- All 2464 fertilising guides in the Growli library