Fertilising guide

How to fertilise 'Borlotto' Bean (Phaseolus vulgaris 'Borlotto Lingua di Fuoco')— schedule & NPK

Also called Borlotti bean, Cranberry bean, Tongue of fire bean.

More about 'borlotto' bean

About 'Borlotto' Bean

Phaseolus vulgaris 'Borlotto Lingua di Fuoco' · also called Borlotti bean, Cranberry bean · edible

'Borlotto Lingua di Fuoco' is an Italian heirloom common bean (Phaseolus vulgaris) grown mainly for drying, with cream pods splashed in fiery red streaks and matching mottled seeds. Available as bush or climbing forms, it is sown after frost, grown for fat shelling beans, and left to dry on the plant before podding for storage.

Growth habit: Available as compact bushy or twining climbing forms; herbaceous annual producing clusters of streaked pods that ripen and dry on the plant.

Watch for — Halo blight and mosaic viruses: Spotting, mottling and stunting spread by aphids or infected seed; control aphids and source certified disease-free seed.

What fertiliser 'borlotto' bean actually wants — and why

'Borlotto' Bean 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 'borlotto' bean: 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 'borlotto' bean, 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 'borlotto' bean:

Minimal feeding needed thanks to nitrogen fixation; a single dose of compost at planting suffices. A light high-potash feed at flowering can improve pod fill in poor soils. 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 'borlotto' bean 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 'borlotto' bean

Follow the crop-feed label rate for 'borlotto' bean — 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 'borlotto' bean first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the 'borlotto' bean watering schedule.

Signs you are over-feeding 'borlotto' bean

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

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 'borlotto' bean

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 'borlotto' bean 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 'borlotto' bean 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 'borlotto' bean

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 'borlotto' bean — frequently asked questions

What fertiliser does 'borlotto' bean 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. 'Borlotto' Bean 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 'borlotto' bean?

Minimal feeding needed thanks to nitrogen fixation; a single dose of compost at planting suffices. A light high-potash feed at flowering can improve pod fill in poor soils. Minimal feeding needed thanks to nitrogen fixation; a single dose of compost at planting suffices. A light high-potash feed at flowering can improve pod fill in poor soils. 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 'borlotto' bean?

What does over-feeding 'borlotto' bean 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 'borlotto' bean 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 'borlotto' bean?