Abstract We tested the efficacy of matrix-based
fertilizers (MBFs) to improve Kentucky bluegrass
(Poa pratensis L.) growth while reducing NH, NO3,
dissolved reactive phosphorus (DRP), and total
phosphorus (TP) compared to commercial slowrelease
fertilizer (SRF) Polyon®, ESN®, and Avail®
in greenhouse column studies. The MBFs covered a
range of inorganic N and P in compounds that are
relatively loosely bound (MBF6) and more tightly
bound compounds (MBF7) with Al(SO4)318H2O
and/or Fe2(SO4)33H2O and with high ionic exchange
compounds starch, cellulose, and lignin. The total
amount of NO3 and NH4 leached was greater from
columns receiving Polyon® and ESN® fertilizers than
all other treatments. The MBF6+Avail® or MBF7+
Avail® fertilizers leached 64–68% less NO3 than
Polyon® (43-0-0) and ESN® (46-0-0), and 73–76%
less TDP and TP than Avail® (10-34-0). A greater
amount of NO3 was leached from the MBF6+Avail®
and the MBF7+Avail® treatments than the other MBF
fertilizer treatments. Shoot and root biomass were
greater when plants received the Avail®, MBF6+
Avail®, and MBF7+Avail® fertilizer treatments than
the other fertilizer treatments. When combined with
small quantities of commercial SRFs, these new MBFs
were able to maintain plant growth while reducing N
and P leaching. These new MBF formulations do not
depend on organic or inorganic coatings to reduce N
and P leaching and with further testing and development
could be effective commercial fertilizers
