pH Affects Seed Germination of Eight Bedding Plant Species

Abstract

Seeds of eight commonly grown bedding plant species [Ageratum houstonianum Mill., Begonia × semperflorens Hort., Impatiens wallerana Hook., Lobularia maritima (L.) Desv., Petunia × hybrida Hort., Pelargonium hortorum L.H. Bailey, Salvia splendens F. Sellow, Tagetes patula] were germinated at pH values from 4.5 to 7.5 at 0.5 increments. Seeds were germinated in petri dishes on filter paper saturated with buffer solutions or in petri dishes containing a 50 sphagnum peat: 50 coarse vermiculite (peatlite) medium moistened with buffer solutions. Germination on filter paper was affected by pH for all species tested. Peatlite medium pH affected germination of all species tested, except Salvia splendens. Species response to similar pH values differed between the two germination procedures. Total percent germination of seeds germinated was less in peatlite medium than on filter paper.