Thresh vs Zyra

Open with Flay (E) before Death Sentence (Q): the slow makes the hook much easier to land.

In lane, space out your autos: Flay (E) charges them passively, and the longer you wait between two autos, the more damage they deal.

Don't recast Death Sentence (Q) on reflex: the target is already being pulled toward you, and jumping on them often exposes you for nothing.

Throw Dark Passage (W) toward an ally in trouble before they need it: they can click it to come back to you, with a shield.

Place The Box (R) right after a successful hook: to escape, the target has to break a wall, and the first wall broken slows them and deals full damage.

Get out of the line of Grasping Roots (E): the roots pass through minions and root every enemy hit, then her plants hit the trapped target.

Step on her seeds to destroy them before she grows them: Rampant Growth (W) seeds reveal you for a moment, but leave her no plant.

Take down the plants born from Garden of Thorns (passive), or back off until they die: they take fixed damage, like a ward, and don't live long.

Get out of the Stranglethorns (R) zone as soon as it appears: the vines knock you into the air 2 seconds later, and her plants are empowered inside.

If you can engage, go for Zyra when her plants are far from her: the Thorn Spitter from Deadly Spines (Q) only fires at 575 range.