Mustard Cake: Fast Organic Nitrogen
The residue left after pressing mustard oil is a fast-acting nitrogen source for vegetables. How to apply it dry or ferment it as foliar feed.
Vaibhav Dhama2 min readOrganicN ~4-5%, P ~1-2%, K ~1%Updated 3 August 2026
Mustard Cake
A fast-release organic nitrogen source from pressed mustard seed — reached for when a vegetable crop needs a push, not a slow build.
- Composition
- N ~4-5%, P ~1-2%, K ~1%
- Form
- Golden-brown cake / powder
- Price
- Moderate-high
- Best for
- Fast organic N for vegetables
Overview
Mustard cake is what remains after mustard seed is pressed for oil. It carries roughly 4–5% nitrogen with a little phosphorus and potassium, and unlike most organic inputs it releases that nitrogen relatively quickly — closer to a fast top-dressing than a slow soil-builder.
It can be worked into the soil dry or fermented in water to make a foliar and soil-drench liquid. Because it competes with the animal-feed market for supply, it is one of the pricier organic nitrogen sources, so growers use it as a targeted boost rather than the bulk of a fertility programme.
What it is and when to reach for it
- A fast-releasing organic nitrogen source — reach for it when a vegetable crop needs a visible push, not for slow, season-long soil building.
- It also supplies a little phosphorus and potassium, but growers reach for it mainly for the nitrogen.
- It doubles as livestock and fish feed, so its price tracks the feed market rather than the fertiliser market.
How to use it well
- Work 100–200 kg/acre into the soil, or apply around the base of vegetable plants and hoe it in.
- Split the dose — part at planting, part as a top-dressing three to four weeks later — since its nitrogen comes fast.
- Ferment 1 kg of crushed cake in 10 litres of water for about a week for a liquid foliar feed, then dilute several times before spraying.
Common mistakes
- Applying the fermented liquid undiluted — the raw ferment is strong enough to scorch leaves and roots.
- Relying on it alone for long-term soil health — it feeds a crop quickly but builds soil less than compost, FYM or green manure.
- Skipping phosphorus where the crop needs more than mustard cake’s modest 1–2% can supply — pair it with bone meal.
Crops it is used on
Open a crop for its full nutrient schedule.
Guides
Long-form guides on this fertiliser, with the rates and timings worked out.
Common questions
How much mustard cake per acre?
Roughly 100–200 kg per acre worked into the soil for a field crop, or applied around vegetables. Because it releases nitrogen relatively quickly for an organic input, split it — some at planting, some as a top-dressing — rather than applying it all at once.
How do I make mustard cake liquid fertiliser?
Soak about 1 kg of crushed cake in 10 litres of water, cover loosely and let it ferment for a week or so, stirring daily. Filter, then dilute the liquid several times before using it as a foliar or soil drench. Never apply it undiluted — the raw ferment can scorch leaves and roots.
Is mustard cake better than neem cake?
Different jobs. Mustard cake releases nitrogen faster, so it suits a crop that needs a quick push. Neem cake is slower and also suppresses nematodes. Many growers use both — mustard cake for a boost, neem cake to build the soil and hold pests down.
Composition and doses follow ICAR / Soil Health Card guidance; prices are the notified subsidised rates for the season shown and are guidance, not a quote. A soil test for your field always beats a general rate. See our editorial policy.