NPK

American  

[en-pee-key] / ˈɛnˈpiˈkeɪ /

abbreviation

1. Horticulture. a ratio of percentages of the three nutrients—nitrogen, phosphorus, and potassium—that are especially important in a plant fertilizer. A fertilizer’s NPK is given as a series of three numbers, for example, 24–6–6, which means the content is 24 percent nitrogen, 6 percent phosphorus, and 6 percent potassium, so the NPK expressed as a simple ratio is 4:1:1.

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Etymology

Origin of NPK

First recorded in 1900–05; from the chemical symbols for nitrogen ( def. ) (N), phosphorus ( def. ) (P), and potassium ( def. ) (K)

Example Sentences

Lucy Bell-Reeves, NPK Recovery's co-founder, said using a waste product to grow trees was "a circular solution that can revitalise our struggling native species."

From BBC • Apr. 2, 2026

Bristol-based start-up NPK Recovery collects urine from portable toilets during festivals and events, transforming it into fertiliser to help grass grow back on the fields afterwards.

From BBC • Apr. 2, 2026

Because organic fertilizers like fish emulsion have very low concentrations of nitrogen and other elements, he recommends a monthly application of a water-soluble food labeled with a 20-20-20 NPK ratio instead.

From Seattle Times • May 1, 2024

Brazil imported 23.6 million tonnes of crop nutrients including potash and formulated products containing NPK through July, a 15.5% rise compared with the same period a year ago.

From Reuters • Aug. 4, 2022

The strategy also likes the price, as NPK trades for just 12.4 times earnings and 1.6 times book value.

From Forbes • Jun. 2, 2014