Three compost products [biosolids (SYT), refuse derived fuel residues (RYT), and municipal solid waste (MSW)] were compared to a commercial bedding plant medium of 60% Sphagnum peat: 25% shredded bark: 15% aerolite to support Impatiens wallerana `Accent Red' growth. The treatments consisted of 100% compost as a stand alone medium plus blends in which compost was combined with control medium components at 60% compost or 30% compost. Shoot dry mass of plants grown in 100% SYT and RYT was greater than shoot dry mass of Impatiens plants grown in 100% MSW. Plants grown in SYT showed an increase in shoot dry mass from 1.29 to 1.64 g as the percentage of compost in the mix increased from 0% to 100%, while plants grown in MSW showed a linear decrease in. shoot dry mass from 1.29 to 0.18 g. Shoot dry mass of plants grown in RYT did not differ significantly from 0% to 100% compost in the media.
Kimberlv A. Klock and George Fitzpatrick
H.M. Mathers, S.B. Lowe, C. Scagel, D.K. Struve and L.T. Case
in the nursery industry today are pine bark, hardwood bark, sand, soil, industrial clays and aggregates, composted yard, garbage and animal wastes such as biosolids/sludge, rice hulls, peanut hulls, mushroom compost, peatmoss, coir (a by-product of
S.M. Scheiber, Richard C. Beeson Jr and Sudeep Vyapari
practices. Incorporation of organic matter or compost in annual landscape beds is widely recommended to improve water and nutrient-holding capacities, particularly in sandy soils ( Warren and Fonteno, 1993 ). However, organic matter is highly variable
Danielle D. Treadwell, Nancy G. Creamer, Greg D. Hoyt and Jonathan R. Schultheis
compost and cover crops are integral components in organic management systems. Compost is applied to promote soil biological activity ( Raviv, 2005 ), suppress disease ( Stone et al., 2003 ), increase soil organic C ( Jackson et al., 2004 ) and supply
George Kotsiris, Panayiotis A. Nektarios and Angeliki T. Paraskevopoulou
( Beattie and Berghage, 2004 ) with an organic matter that varies according to the green roof type ( FLL, 2008 ). In most cases, the organic matter of green roof substrates is composed of peat but composts offer an appropriate alternative in an effort to
Bernadine C. Strik, Amanda Vance, David R. Bryla and Dan M. Sullivan
immobilize a considerable amount of the N applied from fertilizers ( White, 2006 ). Some growers are using compost in addition to sawdust to provide additional nutrients and organic matter ( Gale et al., 2006 ; Larco et al., 2014 ). Municipal yard debris
Allen V. Barker
Activators are suggested as adjuvants to accelerate rates of composting of plant residues. Three activators, two microbial preparations and one enzyme-based material, were assessed. The feedstock for composting was a 1:1 volumetric ratio of vegetative food wastes and autumn leaves from broadleaf trees. Composting was conducted in 0.35-m3, covered, plastic bins. In one experiment, the bins were filled to capacity twice, once at treatment initiation and at 1 week later. Treatments included no activator, an addition of each microbial preparation individually, addition of the enzyme-based activator individually, and additions of one of the microbial preparations and the enzyme-based activator in combination. The individual applications were at full-strength according to recommendations on the labels, and the combinations were at full-strength or at half-strength according to the recommendations. Piles in the bins were turned weekly, and activators were added weekly or only once according to the manufacturers' recommendations. Composting proceeded for 60 days. In a second experiment, the same protocols were followed with the modification that feedstock was added to each bin weekly for 60 days, followed by a 30-day curing period. Temperatures of the compost were recorded weekly. Piles were moistened weekly after turning. None of the activators accelerated the rate of composting relative to the rate with no activators. Rate of composting was evaluated by comparison of the weekly temperatures of the piles, the volume of compost produced, and the texture of the compost. Tomato (Lycopersicon esculentum Mill.) plants grew equally well in composts from each of the treatments. The conclusion was that compost activators did not modify the process or quality of compost produced from food and tree-leaf residues.
Ronnie W. Schnell, Donald M. Vietor, Richard H. White, Tony L. Provin and Clyde L. Munster
soluble nutrients and organic C to soil ( Johnson et al., 2006a ), a high C- to-N ratio of composted municipal biosolids (CMB) reportedly limited turfgrass growth rate and development of dark green color ( Linde and Hepner, 2005 ). If the balance of N
Kimberly K. Moore
The ornamental horticulture industry uses a variety of materials as ingredients in growing substrates for many ornamental plants. There are many attributes that make growing substrates effective, including good aeration and drainage, availability at an acceptable price, and chemical attributes conducive for plant growth. In recent years there has been a trend in which more traditional organic components, such as Canadian sphagnum peat, have been partially replaced by an increasing array of waste-product compost. Plant response to increasing quantities of compost in the potting mix, and to different types of compost are variable. This paper reviews some important issues in the utilization of urban waste compost products.
Theodore J.K. Radovich, Archana Pant, Ian Gurr, Ngyuen V. Hue, Jari Sugano, Brent Sipes, Norman Arancon, Clyde Tamaru, Bradley K. Fox, Kent D. Kobayashi and Robert Paull
imported fertilizers increased from $300 to $1000 per ton between 2006 and 2008, which increased the demand for local organic fertilizers to keep local producers competitive. Compost, meat meal, and seaweeds are good sources of nutrients, although