I think the plants are good, but i miss smite buffs.
The only one i have an issue with is the Scryer, it far outweighs the others in terms of power, being able to sweep almost an entire jungle for wards and champions is just insane. The blast one is fun, i have escaped invades, i have been invaded and they have gotten away too. It is very fun to play around and it rewards a good planner. The health plant is definitely good because it has trade offs, slows you down and you have to go to the river to acquire it. (aka trading clearing time for hp/mana)
that being said i do miss smite buffs. Either add new plants to do more interesting things and lower the spawn rate of scryer or balance is better and i think they will end up being pretty good overall.