I made this Winter's Kiss farming guide to help out players who want to farm the herbs instead of buying them from the Auction House. You can pick Winter's Kiss with BfA Herbalism skill 1, but the rank 2 and rank 3 requires higher Herbalism skill. Higher ranks allow you to gather this herb more effectively, so you will get more herbs overall.
Winter's Kiss
Winter's Kiss ranks
You will learn rank 1 from your Herbalism trainer at Daz'Alor / Boralus.
Rank 2 is a reward from a small quest chain which starts with 
Meet Sweetflower and ends with Can't Teach on an Empty Stomach. The quest chain unlocks at BfA Herbalism 50, and is given to you by your Herbalism trainer at Daz'Alor / Boralus.
Ranks 3 is a reward from the quest The Frigid Boon. You can get this get after you loot one 
[The Frigid Boon] while gathering Winter's Kiss. It's not 100% drop, and you will need around Herbalism 130 before it can drop for you.
How to speed up farming
Battle for Azeroth introduces three new items that you can use to speed up farming herbs. You should use these if you can find them cheap at the Auction House, or craft it yourself if you can.
[Monel-Hardened Stirrups] - You can gather while mounted.
[Monel-Hardened Hoofplates] - Increase mount speed by 20%.
[Coarse Leather Barding] - Prevents you from being dazed. (mobs won't dismount you)
The one I would recommend the most is [Monel-Hardened Stirrups], which lets you gather herbs while mounted. Every mob scales to your level in Battle for Azeroth, so it will be hard to avoid the mobs attacking you while you try to farm herbs. If you have the 
[Sky Golem] mount, you can use that instead of the Monel-Hardened Stirrups
If your class has a tanking spec, you should switch to that while farming, so you won't get dazed and you don't have to use Coarse Leather Barding.
Don't forget to enchant your gloves with 
[Enchant Gloves - Zandalari Herbalism] or [Enchant Gloves - Kul Tiran Herbalism]! This enchant brings gathering time down from 1.5 seconds to 0.5 seconds. This is really important if you gather while mounted because mobs can still interrupt your casting.
Drustvar - route 1
This route goes through an Alliance town, so horde players might have some trouble here, but you can just run past the guards with mount, they shouldn't kill you.
Drustvar - route 2
Use this route if someone is already farming at the first route, or if you are having trouble going through the Alliance town.
Drustvar - route 3
You will also get some Star Moss, Anchor Weed, and Siren's Pollen here. This is not that good if you only want to get Winter's Kiss, but a great alternative for farming if the other two routes are already taken by someone.
Drustvar - route 4
You will only find Winter's Kiss at Gol Koval, but there are usually 7-8 Herbs there, so you can still get a decent amount of Winter's Kiss, but this is nowhere near as good as the first two routes.
