fastest ~1m/sec: slowest (some hormones) ~1cm/hour: most (thorough vascular system) 1-8mm/sec
||Trewavas A. The foundations of plant intelligence. Interface Focus. 2017 Jun 6 7(3):20160098. doi: 10.1098/rsfs.2016.0098. p.6 left column 2nd paragraphPubMed ID28479977
||P.6 left column 2nd paragraph: "Probably the fastest communicating signal moves through plant tissues at about 1 m/sec and the slowest at about 1 cm/hour for some hormones. But most average 1–8 mm/sec through the vascular system. The action potential was first reported over a century ago in the sensitive Mimosa and even earlier in the Venus fly trap [ref 39]. Mechanical signals may operate directly through mechano-sensitive calcium channels [refs 45, 57]."