Fertilising guide

How to fertilise Mung Bean (Vigna radiata)— schedule & NPK

Also called Mung Bean, Green Gram, Golden Gram, Moong.

More about mung bean

About Mung Bean

Vigna radiata · also called Mung Bean, Green Gram · edible

Mung bean is a fast-growing warm-season annual legume widely cultivated for its protein-rich seeds and edible sprouts. It fixes atmospheric nitrogen, improving soil fertility. Plants mature in 60–75 days and tolerate heat and moderate drought. Seeds are eaten whole, split as dal, or sprouted; young leaves are also edible.

Growth habit: Erect, bushy annual with trifoliate leaves; nitrogen-fixing root nodules. Pods borne in clusters near top of plant.

What fertiliser mung bean actually wants — and why

Mung 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 mung 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 mung 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 mung bean:

Light phosphorus and potassium application at planting. Use Rhizobium group inoculant on seeds before sowing to maximise nitrogen fixation. Avoid nitrogen-heavy fertilisers; the plant provides its own supply through root nodules. 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 mung 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 mung bean

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

Signs you are over-feeding mung bean

Over-feeding is far more common — and more damaging — than under-feeding for most plants. The classic tells for mung 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 mung 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 mung 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 mung 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 mung 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 mung bean — frequently asked questions

What fertiliser does mung 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. Mung 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 mung bean?

Light phosphorus and potassium application at planting. Use Rhizobium group inoculant on seeds before sowing to maximise nitrogen fixation. Avoid nitrogen-heavy fertilisers; the plant provides its own supply through root nodules. Light phosphorus and potassium application at planting. Use Rhizobium group inoculant on seeds before sowing to maximise nitrogen fixation. Avoid nitrogen-heavy fertilisers; the plant provides its own supply through root nodules. 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 mung bean?

What does over-feeding mung 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 mung 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 mung bean?