Fertilising guide

How to fertilise Nasturtium 'Empress of India' (Tropaeolum majus 'Empress of India')— schedule & NPK

Also called Garden nasturtium, Indian cress.

More about nasturtium 'empress of india'

About Nasturtium 'Empress of India'

Tropaeolum majus 'Empress of India' · also called Garden nasturtium, Indian cress · edible

'Empress of India' is a compact, bushy nasturtium with deep blue-green leaves and vivid crimson-scarlet flowers. Both peppery leaves and flowers are edible, and it flowers best on poor soil in full sun. A fast, trouble-free hardy annual, it sows direct after frost, trails or mounds well in beds and pots, and self-seeds freely.

Growth habit: Compact, mounding to lightly trailing bushy annual with rounded leaves, well suited to bed edges, baskets and containers.

Watch for — All leaves, no flowers: Soil too rich or over-fertilised drives lush foliage. Grow in poor soil and withhold feed to push flowering.

What fertiliser nasturtium 'empress of india' actually wants — and why

Nasturtium 'Empress of India' feeds in two distinct phases — balanced to build the plant, then high-potassium the moment flowering starts to set and fill a heavy crop.

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 nasturtium 'empress of india': 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 nasturtium 'empress of india', 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 nasturtium 'empress of india':

Do not feed for flowers. On very poor soil a single weak balanced feed is enough; nitrogen-rich fertiliser gives masses of leaves and very few flowers, the classic nasturtium mistake. So: a balanced feed or compost at planting, then a high-potash liquid every 1-2 weeks from first flower through harvest across the main season (spring through early autumn).

The dormant-season rule matters more than the exact interval: skip feeding entirely when nasturtium 'empress of india' 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 nasturtium 'empress of india'

Follow the crop-feed label rate for nasturtium 'empress of india' — these are calibrated for hungry vegetables. Consistency through fruiting matters more than strength; erratic feeding causes problems like blossom-end rot.

Feeding always goes onto already-damp soil, never dry roots — water nasturtium 'empress of india' first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the nasturtium 'empress of india' watering schedule.

Signs you are over-feeding nasturtium 'empress of india'

Over-feeding is far more common — and more damaging — than under-feeding for most plants. The classic tells for nasturtium 'empress of india':

Vigorous dark-green leafy growth but few flowers or fruit (excess nitrogen).
Lush foliage hiding the crop; soft growth prone to pests and disease.
Salt crust on the soil and scorched leaf edges in containers.

Signs you are under-feeding nasturtium 'empress of india'

Pale, yellowing lower leaves and stunted growth.
Small fruit, poor set, and a quickly exhausted plant.
Blossom-end rot and weak cropping from erratic or insufficient feeding.

If the symptoms point at watering, light or roots rather than nutrition, the full nasturtium 'empress of india' care brief covers soil, humidity and the common problems for this species.

Flushing and leaching the salts

In containers, fertiliser salts build up fast — water nasturtium 'empress of india' thoroughly so excess drains from the base each time, and flush pots with plain water every few weeks to prevent a damaging salt build-up.

Organic vs synthetic feeds for nasturtium 'empress of india'

Organic options

Garden compost or well-rotted manure dug in before planting, plus a liquid comfrey or seaweed feed once fruiting starts. UK: comfrey feed or organic Tomorite; US: Espoma Tomato-tone or Neptune's Harvest. Builds soil and feeds in one.

Synthetic / liquid feeds

A balanced feed at planting then a high-potash tomato feed in fruiting — UK: Growmore at planting then Tomorite (Levington) or Phostrogen; US: a balanced 10-10-10 then Miracle-Gro Tomato or a bloom booster.

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 nasturtium 'empress of india' — frequently asked questions

What fertiliser does nasturtium 'empress of india' need?

Balanced (even N-P-K) at planting for roots and frame, then switch to a high-potassium ("high-potash") tomato-style feed once the first flowers open — potassium is what sizes and ripens fruit, not nitrogen. Nasturtium 'Empress of India' feeds in two distinct phases — balanced to build the plant, then high-potassium the moment flowering starts to set and fill a heavy crop.

How often should I feed nasturtium 'empress of india'?

Do not feed for flowers. On very poor soil a single weak balanced feed is enough; nitrogen-rich fertiliser gives masses of leaves and very few flowers, the classic nasturtium mistake. Do not feed for flowers. On very poor soil a single weak balanced feed is enough; nitrogen-rich fertiliser gives masses of leaves and very few flowers, the classic nasturtium mistake. So: a balanced feed or compost at planting, then a high-potash liquid every 1-2 weeks from first flower through harvest across the main season (spring through early autumn).

What strength of feed for nasturtium 'empress of india'?

What does over-feeding nasturtium 'empress of india' look like?

Vigorous dark-green leafy growth but few flowers or fruit (excess nitrogen). Lush foliage hiding the crop; soft growth prone to pests and disease. Salt crust on the soil and scorched leaf edges in containers. Staying on a high-nitrogen feed once nasturtium 'empress of india' starts flowering is the classic error — you get a huge leafy plant and a disappointing crop. Switch to high-potash the moment flowers appear.

Should I flush the soil of nasturtium 'empress of india'?