Because Noblegarden has been extensively reworked, most of what you'll be doing this year is completely new, and some of this guide is going to be comprised of educated (or not-so-educated) guesses as to the difficulty of the achievements on the live realms, and tips on how to get them done. I'll let you know if I just plain don't know something or have to hazard a guess based on PTR information, but fortunately most of the holiday is pretty straightforward. We're only going to cover the achievements you need to worry about for the meta, as everything else you can achieve is really based on luck and doesn't count toward Noble Gardener.
Let's get started!
First things first; you'll want to read our Noblegarden FAQ if you're completely new to the holiday.
Otherwise, these are the basics of the new and improved Noblegarden:
As with Hallow's End, much of the content is centered in and around level-5 towns (e.g. Azure Watch, Dolanaar, Goldshire, and Kharanos for Alliance, and Bloodhoof Village, Brill, Falconwing Square, and Razor Hill for the Horde). Brightly Colored Eggs will spawn in and around these towns for the duration of the celebration (April 26th through May 2nd 2009 or April 4th through April 11th in 2010).
The number of eggs spawned has been massively increased. Judging from what Kisirani wrote on the forums, any player's looting of one egg should automatically spawn another elsewhere. You should have very little difficulty getting enough eggs, although you will likely face competition for the spawn points if you choose to do the holiday in its earliest days.
Buying all of the items you'll need will run you a total of 365 chocolates. This may sound like a lot, but many of the achievement-linked items can also be discovered randomly in eggs. If you get reasonably lucky, you probably won't need 365.
Completing the meta-achievement Noble Gardener will reward the title "(Name) the Noble."
For all those of us who love having Sting trapped in our heads, but this isn't too tough. You'll need Spring Robes (which allow you to plant a flower on a 1-minute cooldown) from a Noblegarden vendor, and that'll run you 50 Noblegarden chocolates or a lucky drop. 4 out of the 5 locations here are in Kalimdor, which will cut down on your travel time somewhat, but you'll still need to make the hike to the Badlands at some point.
The easiest way to do this (short of getting lucky with an egg granting the Noblegarden bunny buff) is to head down to Un'goro with friends who've bought the Blossoming Branch (which is a very easy purchase for 10 Noblegarden chocolates). The Hot Springs are the lake area to the west of the central mountain in Un'goro. Head down, have your friend cast the buff, and wait until you lay an egg (it's a periodic trigger). Be sure to bring your own Branch so you can return the favor.
If you do get the bunny buff from a random egg, it's entirely possible to just run down to Un'goro without any outside help, but be forewarned that you'll lose the buff by shapeshifting, mounting, or taking a flight path. It's a lot less time-consuming to grab a buddy and fly down to Un'goro.
This achievement requires the purchase of a Noblegarden egg from a vendor (5 chocolates). If you're Horde, head to Silvermoon; if you're Alliance, head to Stormwind. Right-click your egg to spawn a Brightly Colored Egg, and you're all set. Interestingly, you can loot the egg after you place it, thus "refunding" yourself a chocolate.
In addition to saving enough chocolates for the purchase of items you need for achievements, you'll need to eat 100 over the course of the week. This sounds like a lot, but it amounts to a little less than 15 chocoates a day if you ration it out instead of saving them up and eating them in one big marathon.
This one will run you 100 Noblegarden chocolates in order to buy the new noncombat pet, the Spring Rabbit. What do you get for your hard-won confectioneries? The pet has a fairly unique behavior; like Stinker, it falls in love, but -- unlike absolutely everything else in this T-rated game, which is a pity -- it makes babies. Leave your Spring Rabbit in proximity to someone else's Spring Rabbit and...you'll get more rabbits. Parents may want to keep their own small offspring away from the monitor for the duration of this holiday unless they want the subject of "the talk" to be prompted by pixelated rabbit goings-on.
I think the highlight of my playing experience in the near future will be seeing a raid full of players with Spring Rabbits out. 10-mans should see 5 nice stable rabbit pairs, but question for 25-mans; is the odd rabbit out left alone, or does he become part of a, um, threesome? And why am I allowing my mind to roam places that frighten and disturb me?
Oh, the achievement. Right. Uh, bring your rabbit to each of the four level-5 towns for your faction and wait for something beautiful and natural to happen with someone else's rabbit. There you go. Does that make you kind of a rabbit pimp? I think it does. I also think I need to stop laughing before I am required to spend the next twenty years of my life in a confessional just because I find this funny.
The player Lostshard on the PTR got video of the bunny and its behaviors, which I've embedded at the bottom of the post if you're interested.
Wow, I'm glad I'm no longer required to write about uncomfortable subjects. Next on the agenda will be placing bunny ears on nubile 18+ players. I mean, level 18+, of course. In the game! The game! Get your mind out of the gutter. You'll need to buy Spring Flowers for 50 chocolates, which let you place bunny ears on other players. You can place bunny ears on your own toon (helpful if you play a female, which lets you knock one of the requirements out right off the bat), but otherwise you're going to have to start hunting down female toons of each race.
As the Wowhead thread notes, on some realms it's pretty hard to find females of certain races (e.g. Trolls, Orcs, Tauren, and Dwarves). If you get desperate and don't yet have a Death Knight, the most expedient means of getting this achievement done might be rolling a female DK of the race your friends need, and having them summoned somewhere convenient (and then having a friend do the same for you).
Please note that the formalwear described in this achievement isn't the white-quality Tailoring stuff anybody can get; you'll need to get these pieces as drops from eggs, or buy them from a Noblegarden vendor. The pants and shirt cost 25 chocolates each, and the dress costs 50, so count on spending at least 50 chocolates for this.
Once you add up all of the items you'll need for the meta-achievement, with a worst-case scenario (i.e. very unlucky with drops from eggs, and you have to buy everything) you'll need to have 365 chocolates stashed away (add 50 more if you also buy an Elegant Dress to help friends who need Blushing Bride). Don't forget that you've got until April 11th to get this done, however. Good luck, and happy hunting!