Track sprayer and field sprayer trials were completed to assess the effect of different nozzles, surfactants and carrier volumes on product delivery to the inner leaves of onion plants using a fluorescent tracer. Track sprayer trials revealed more tracer on the inner leaves of onions using either the TeeJets XR8004 flat fan or D4/DC25 disc-core hollow cone nozzles. In three of four experiments, more tracer was detected on onions sprayed alone or combined with Sylgards 309 at 200 L/ha than plants sprayed with tracer+Companions. When the carrier volume was increased to 400 L/ha, more tracer was detected on onions sprayed alone or combined with Companion. In field trials, the XR8004 delivered more tracer than the D4/DC25 (F ¼ 32.8; Po0.00; d.f. ¼ 1,77). The best coverage was observed on plants sprayed with the flat fan combined with Agrals 90, sprayed at either 400 L/ha (29% coverage) or 600 L/ha (23% coverage).