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Fertilising guide

How to fertilise Agastache 'Blue Fortune' (Agastache 'Blue Fortune')— schedule & NPK

Also called Blue Fortune hyssop, Anise hyssop.

More about agastache 'blue fortune'

About Agastache 'Blue Fortune'

Agastache 'Blue Fortune' · also called Blue Fortune hyssop, Anise hyssop · flowering

A robust, award-winning anise hyssop hybrid (A. foeniculum x rugosa) topped from midsummer into autumn with dense, powder-blue bottlebrush flower spikes. The anise-scented foliage is loved by bees and butterflies and shunned by deer. More cold- and wet-tolerant than most Agastache, this upright, sterile-flowered perennial blooms for months and makes a magnet for pollinators in sunny borders.

Growth habit: Upright, clump-forming herbaceous perennial with sturdy stems topped by long-lasting flower spikes. Sterile (sets little to no seed), so it blooms longer and does not self-sow aggressively.

What fertiliser agastache 'blue fortune' actually wants — and why

Agastache 'Blue Fortune' 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 agastache 'blue fortune': 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 agastache 'blue fortune', 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 agastache 'blue fortune':

Very light feeder; thrives in lean soil. A light spring compost top-dressing is sufficient. Avoid rich feeding and excess nitrogen, which cause weak, floppy stems and reduced 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 agastache 'blue fortune' 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 agastache 'blue fortune'

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

Signs you are over-feeding agastache 'blue fortune'

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

Signs you are under-feeding agastache 'blue fortune'

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

Flushing and leaching the salts

Flush the pot of agastache 'blue fortune' 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 agastache 'blue fortune'

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 agastache 'blue fortune' — frequently asked questions

What fertiliser does agastache 'blue fortune' 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. Agastache 'Blue Fortune' 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 agastache 'blue fortune'?

Very light feeder; thrives in lean soil. A light spring compost top-dressing is sufficient. Avoid rich feeding and excess nitrogen, which cause weak, floppy stems and reduced flowering. Very light feeder; thrives in lean soil. A light spring compost top-dressing is sufficient. Avoid rich feeding and excess nitrogen, which cause weak, floppy stems and reduced 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 agastache 'blue fortune'?

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

What does over-feeding agastache 'blue fortune' 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 agastache 'blue fortune' 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 agastache 'blue fortune'?

Flush the pot of agastache 'blue fortune' 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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