NOVELTY - Composting green waste comprises: forming a mulch of screened green waste consisting of grass and hedge cuttings and adding to this 2-5% dry weight of a density modifier and optionally a nitrogen additive; pre-wetting the mulch mixture for 20-100 hours; wetting, blending and rotating the mulch mixture for 3-4 days; arranging the mulch mixture in rows or stacks and turning it every 24 hours for 4-5 days; adding further water to obtain a moisture level of 75%; and pasteurizing the mixture.    USE - The method is useful for composting green waste, which is useful as a growth media for fungi (claimed).    ADVANTAGE - The method provides the growth medium: for growing fungi with enhanced flavor and shelf life; which completely avoids the use of animal by-products, particularly excreta; in significantly less time with desired characteristics of nutrient base, nitrogen levels and growth progression for cultivation of fungi; which reduces composting time from 15 days to 8 days; and with reduced amounts of certain additives e.g. nitrogen additives, Sporavite (RTM: Compost activator rich in molasses) and various growth enhancers that may be reduced without affecting overall growth characteristics. The method provides faster mycelial growth and increased mushroom yield.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for:    (1) growth media for fungi, comprising the mulch of green waste, density modifier and nitrogen additive;    (2) a growth medium for enhancing growth and availability of water and nutrients during the growth progression of spawn into harvestable fungi, comprising the screened mulch of green waste, the density modifier, the nitrogen additive and a casing material, where the growth medium is capable of retaining a substantially evenly distributed reservoir of moisture within it;    (3) growing fungi of enhanced flavor and shelf life comprising: forming a bed of growth media formed from the mulch of green waste which includes an inoculum of the desired species of fungi; overlaying the bed of growth media with the casing material having suitable moisture retaining properties; elevating the ambient temperature and carbon dioxide levels to that known to be optimum for the species of the inoculum; and harvesting the fungi, where the mulch precludes the use of animal excreta and like materials, thus avoiding substantial contamination with bacteriological agents, and thus the fungi produced have increased shelf life and coincidentally enhanced flavor characteristics;    (4) mushroom spawn comprising growth media formed from the mulch of green waste and inoculum of the desired species of fungi, where the growth medium is prepared using graded green waste with a density modifier, and provides a source of nutrition for the mycelia and the density modifier ensures the structure of the medium to ensure adequate oxygenation, thus faster mycelial growth and increased mushroom yield is realized;    (5) making the mushroom spawn comprising the growth medium and inoculum of the desired species of fungi or already-formed mycelia;    (6) the casing material comprises a finely graded mulch of green waste and peat in a ratio of 4:1 and 2:3 (80:20-40:60% dry weight), having a pH modifier to control the pH to 6.6-7.8 (a pH of in the region of 8.8 when taken as a 1:5 dry extract is considered acceptable) and added water to adjust the moisture content to 74-76%;    (7) a growth medium (I) for fungi comprising the screened mulch of green waste and the density modifier, where the growth medium has a composition (measured as on a dry matter basis in) including ammonium nitrogen (12 mg/kg), nitrate nitrogen (106 mg/kg), phosphorus (1732 mg/kg), potassium (8753 mg/kg), magnesium (1623 mg/kg), sodium (1010 mg/kg), calcium (22958 mg/kg), sulfur (1655 mg/kg), iron (11006 mg/kg), manganese (205 mg/kg), where the medium has a bulk density of 350 g/l, and a water holding capacity of 50-76%;    (8) a compost material suitable for domestic and more general horticultural use, where the compost material comprises the green waste mulch based growth media; and    (9) a soil cleanser and/or improver comprises the green waste mulch based growth media.