Flood subirrigation systems for greenhouse production and the potential for disease spread

There was no significant difference between plant height, dry weight, flower number or postharvest quality of poinsettias 'Gutbier V-14 Glory' (Euphorbia pulcherrima) or Easter Lily 'Nellie White' (Lilium longiflorum) when grown using topwatering or flood subirrigation.; Geraniums (Pelargonium X hortorum L. H. Bailey 'Ringo Scarlet') were grown in trays which contained 3 non-inoculated plants and one plant inoculated with Pythium ultimum which were topwatered or subirrigated with recycled solution. Spread of P. ultimum occurred into water and into plants.; Geraniums inoculated with P. aphanidermatum were grown in trays which contained non-inoculated geraniums in either Baccto, Baccto drenched with metalaxyl or Naturally Suppressive Ball Growing Mix 2. There was no significant difference in spread of P. aphanidermatum between plants grown with either irrigation system or between plants grown in either media.