Thanks for the suggestions. I do all the other stuff (low quality, spam the button, position mouse in advance etc.).

Currently I use

Alpinia (700 Spd, + 150 Squad Spd)
Anthurium (not evolved as only level 32, 700 Spd)
Edelweiss (515 Spd, + 50 Squad Spd)
Setaria (720 Spd)
Gaillardia (560 Spd, + 50 Squad Spd)

My squad speed is 889.

I take out Anthurium or Setaria and my squad speed drops.

Dipladenia is only level 32 at the moment too. I will try go evolve one of Anthurium/Dipladenia for next time!