I was looking up some estimates of who the best supports are this season, and I'm not sure why she isn't at the top.
She only has to build 30% CDR to achieve 45% by lvl 9. And her root doesn't require you to position around minions. I'll grant you her Q is weak, but save it for a W combo and I think she's nothing short of vicious. As I'm seeing it predicted, the top supports are Janna, Soraka, Leona, Nautilus, Zilean.
Or are people seeing other options.
Epic Murph6 votesi think it's because she's really squishy early game. Especially when everyone has thunderlords
Zero Skill Tank1 votesThis. She is squishy as hell and has no sustain whatsoever to mitigate the poke, and that + 0 mobility grants her Teemo's level of global taunt.
Twink Lover 694 voteslol. if you're maxing your plants by lvl 9, then you're playing her wrong.
She needs either her vines or Q maxed first. Without both of those maxed first, she is effectively useless.
The plants are just there for extra poke or the added slow combo.
Also, her Q is massive. It hits like a truck. Plus it's AOE.
Maybe you should play more games with her before posting about it.
RookPusher3 votes[{quoted}](name=Prince of Punjab,realm=NA,application-id=3ErqAdtq,discussion-id=2NFEjNcp,comment-id=0001,timestamp=2016-01-19T16:09:17.010+0000)
Maybe you should play more games with her before posting about it.
Maybe you should socialize more before attempting a civil discussion.
Cowgirl Ed2 votesBecause she's a mage and not a real support and Riot doesn't like her going mid?
1374342 votesHer root, while it goes through minions, is slow and she can easily be bullied out of lane/usefulness if she is against an aggressive adc/support.
Ravenhale2 votesZyra is #3 for lowest health in the game (bested only by Gnar and Heimerdinger). Think of her in Sona terms but with less reliable poke and no sustain. She's very reliant on hitting her E which really needs the Lux Q treatment (mana cost reduced by 20 at all levels).
Verxint2 votesSame reason Vel'Koz support isn't a thing
Because Annie exists in her current state.
BluePolarizer2 votesIf you are looking for a poke support, even Sona is safer while Lulu/Annie need less gold and Brand/Vel'Koz scale better.
TeemoJenkins1 votesI use Morgana support, as Thunderlords on her presently is ridiculously good. Zyra's mana costs are so prohibitive that spamming with her runs you dry quickly so other supports who have a better AA range, are more often picked. Her Ult is money in a bot lane, and in later team fights - but she takes a while to get to where that ult is actually relevant damage wise instead of just CC.
VictoryDance961 votesShe is very slow and squishy. She has a lot of good points to be sure, but in a tank meta she can't really fit.
coeurloyal2 votesThe tank meta effectively died with the preseason changes... people are referring to the current state as the 'adc meta'. Tanks lost a lot of power because of all the cheap access to armor shred--which is why we no longer see champs like Maokai, Nautilus, Sejuani, and Gragas.
That being said, poke supports like Zyra/Karma/Vel'Koz aren't very popular in high level play because people tend to look for more utility in their supports and rely on actual carries to bring dps to the party. The one exception we've seen to the rule was support Brand, who only saw play because he was completely broken in terms of base damage. High damage supports like these also tend to be very squishy and need to itemize damage over defensive stats in order to stay relevant, which puts them in a bad spot come mid game because they'll have neither the damage to match the carries nor the defensive stats to stay alive in a fight.
That being said, I think Zyra is incredibly strong in a normal game. She has high DPS, good security with her E, and huge teamfights.
Boulderox1 votesplaying her in aram, you find she can't last long AT ALL (aram is only time i actually play her that is). Her damage is nice, and her spells are very good, but she doesn'tt have anything after she uses her root, her seeds are her true damage form and they are weak and limited when compared to 
turrets persay.
Titanium701 votesZyra has just nothing to offer for her her carry because she was designed to be an APC! Her CC is just enough to peel of some threads. Additionally everything Zyra does is delayed which can be a real problem if the enemy is somehow mobile.
Zyra is still a nice pick if your Team needs some DMG and offensive CC.. but let's be honest. More Jgl gold and Juggernauts doesnt create such scenarios often. Those guys actually create more threads for the ADCs and thats why you need even more peel/utility than before.