Effects of compost media on growth and flowering of parviflorous garden pansy (Viola x wittrockiana Gams.). Part II. Plant flowering and decorative value

Abstract

The purpose of the studies was to determine the effects of media containing composts from sewage sludge and potato pulp on the flowering and decorative value of 'Butterfly Yellow with Blotch' parviflorous pansy. In the experiment 14 potting media, including 12 media made of 4 composts, were tested. The percentage of compost mixed with sphagnum peat was 25%, 50% and 75%. The components of particular composts were as follows: I - municipal sewage sludge 70% and straw 30%; II - municipal sewage sludge 70% and sawdust 30%; III - municipal sewage sludge 35%, potato pulp 35% and straw 30%; IV - municipal sewage sludge 35%, potato pulp 35% and sawdust 30%. Two control potting media were used: 1 - sphagnum peat with Osmocote Exact Lo-Start at the dose 5 g×dm^-3 and 2 - sphagnum peat with Azofoska at the dose 2.5 g×dm^-3. There was no top-dressing during cultivation. The pansies for whose cultivation a slow-release fertiliser was used turned out to have most flowers, but the plants cultivated in compost with peat at the ratio 1:1 had equally abundant flowering. At the generative stage, the pansies in control media were the most decorative and those growing in 25% of compost I, 75% of compost II and 50% of compost III and IV. On the basis of plant valuation scale, quality assessment and the abundance of flowering it was found that the media containing 50% of composts were optimal for pansy cultivation.