Fertilising guide
How to fertilise Water Forget-me-not (Myosotis scorpioides)— schedule & NPK
Also called Water Forget-me-not, True Water Forget-me-not, Scorpion Grass.
More about water forget-me-not
About Water Forget-me-not
Myosotis scorpioides · also called Water Forget-me-not, True Water Forget-me-not · flowering
Water Forget-me-not is a delightful native European perennial producing a long succession of tiny, sky-blue flowers with yellow eyes from May to September along stream banks, pond margins, and in boggy ground — one of the longest-flowering native marginal aquatics. Its creeping stems root at the nodes, forming a mat of soft, hairy, lance-shaped leaves that spread across the water surface. A magnet for bees and hoverflies and an excellent wildlife pond plant. Not listed as toxic to cats or dogs by the ASPCA.
Growth habit: Low, spreading, semi-aquatic perennial with creeping stems that root at nodes; soft, hairy, lance-shaped leaves; small, five-petalled, sky-blue flowers with yellow eye produced in curling cymes (typical scorpioid cyme of the Boraginaceae family)
What fertiliser water forget-me-not actually wants — and why
Water Forget-me-not 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 water forget-me-not: 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 water forget-me-not, 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 water forget-me-not:
Little or no feeding required. In aquatic baskets, one slow-release fertiliser tablet in spring provides enough nutrition for the season. Over-feeding promotes lush, soft growth susceptible to powdery mildew and reduces the long flowering period. 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 water forget-me-not 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 water forget-me-not
Half strength is the safe default for water forget-me-not — 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 water forget-me-not first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the water forget-me-not watering schedule.
Signs you are over-feeding water forget-me-not
Over-feeding is far more common — and more damaging — than under-feeding for most plants. The classic tells for water forget-me-not:
- 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.
Signs you are under-feeding water forget-me-not
- Uniformly pale or yellow-green leaves, oldest first.
- Noticeably small new leaves and stalled growth in good light and season.
- A generally tired, lacklustre look despite correct watering and light.
If the symptoms point at watering, light or roots rather than nutrition, the full water forget-me-not care brief covers soil, humidity and the common problems for this species.
Flushing and leaching the salts
Flush the pot of water forget-me-not 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 water forget-me-not
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 water forget-me-not — frequently asked questions
What fertiliser does water forget-me-not 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. Water Forget-me-not 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 water forget-me-not?
Little or no feeding required. In aquatic baskets, one slow-release fertiliser tablet in spring provides enough nutrition for the season. Over-feeding promotes lush, soft growth susceptible to powdery mildew and reduces the long flowering period. Little or no feeding required. In aquatic baskets, one slow-release fertiliser tablet in spring provides enough nutrition for the season. Over-feeding promotes lush, soft growth susceptible to powdery mildew and reduces the long flowering period. 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 water forget-me-not?
Half strength is the safe default for water forget-me-not — houseplant feeds are formulated strong, and the diluted dose is gentler on the roots while still ample for foliage.
What does over-feeding water forget-me-not 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 water forget-me-not 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 water forget-me-not?
Flush the pot of water forget-me-not 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.
Keep reading
- Water Forget-me-not care — the full brief (light, soil, humidity, problems, pet safety)
- How often to water water forget-me-not — 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 prunus maackii
- How to fertilise arisaema griffithii
- How to fertilise arisaema consanguineum
- All 10153 fertilising guides in the Growli library