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Fertilising guide

How to fertilise Eryngium bourgatii 'Picos Blue' (Eryngium bourgatii 'Picos Blue')— schedule & NPK

Also called Picos Blue Mediterranean sea holly.

More about eryngium bourgatii 'picos blue'

About Eryngium bourgatii 'Picos Blue'

Eryngium bourgatii 'Picos Blue' · also called Picos Blue Mediterranean sea holly · flowering

'Picos Blue' is a compact Mediterranean sea holly prized for intense violet-blue flower cones and silver-veined, deeply cut basal foliage. A tough, sun-loving, drought-tolerant perennial from Spanish mountain origins, it suits gravel gardens and dry borders. The spiny bracts attract bees and dry beautifully, giving long-lasting summer structure and colour.

Growth habit: Compact, clump-forming herbaceous perennial forming a tidy rosette of marbled, spiny leaves topped by branched stems of small, intensely blue cone-and-bract flowers.

Watch for — Leggy, pale growth: Caused by shade or too-rich soil; bracts lose their violet intensity. Grow in full sun and lean ground.

What fertiliser eryngium bourgatii 'picos blue' actually wants — and why

Eryngium bourgatii 'Picos Blue' 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 eryngium bourgatii 'picos blue': 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 eryngium bourgatii 'picos blue', 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 eryngium bourgatii 'picos blue':

Not needed. This species performs best in poor soil; fertiliser encourages lush, floppy foliage at the expense of colour and longevity. Omit feeding entirely. 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 eryngium bourgatii 'picos blue' 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 eryngium bourgatii 'picos blue'

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

Signs you are over-feeding eryngium bourgatii 'picos blue'

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

Signs you are under-feeding eryngium bourgatii 'picos blue'

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

Flushing and leaching the salts

Flush the pot of eryngium bourgatii 'picos blue' 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 eryngium bourgatii 'picos blue'

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 eryngium bourgatii 'picos blue' — frequently asked questions

What fertiliser does eryngium bourgatii 'picos blue' 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. Eryngium bourgatii 'Picos Blue' 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 eryngium bourgatii 'picos blue'?

Not needed. This species performs best in poor soil; fertiliser encourages lush, floppy foliage at the expense of colour and longevity. Omit feeding entirely. Not needed. This species performs best in poor soil; fertiliser encourages lush, floppy foliage at the expense of colour and longevity. Omit feeding entirely. 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 eryngium bourgatii 'picos blue'?

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

What does over-feeding eryngium bourgatii 'picos blue' 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 eryngium bourgatii 'picos blue' 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 eryngium bourgatii 'picos blue'?

Flush the pot of eryngium bourgatii 'picos blue' 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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