Brown Thumb Ach. Fail -- Any ideas?

In the Fell Foliage group mission, there is the Brown Thumb Achievement.

It reads: "Kill all the sprouting succulents before they can mature."

So... we planted the seed and killed the Monstrous.

I then tanked the Cactiikii and the Bludgeoning, while the rest took out the sprout.

Then we all took out Cactiikii and the Bludgeoning in short order.

I am not a tracker -- but we took them out fast and as far as I know another Sprout did not appear.

Any idea what went awry here? Is this achievement really about just taking out the boss and ignore the sprout? Or could it be bugged?

You may have missed one, they aren't always close. I used a hot key to target the sprout.

As did we. I talked to the tracker in group and was told nothing came up.

You likely missed one. Depending on your dps/lag it may have even spawned as you were finishing off the boss.

Where did you setup camp?

I seem to remember fighting in the hall way leading from the town to the NPC. It helped confine where the adds popped.

There were two achievements:
1 - allow the sprouts to grow up and merge into mega mob.
2 - keep all the sprouts down.

You need to get on them early. You've got like 15-20s to kill them. Finding the little green disks can be challenging and depending on where you fight they can actually pop in places you can't get to them.

Step one: keep doing what your doing from previous attempt.

Step two: hold him at 10% health. Wait for a fresh seed to spawn.

Step three: kill seed and boss in quick succession.

Might be the key.