Greenhouse #1 Lesson
Here we are, inside our first Greenhouse! This area, as well as the second Greenhouse, will cover the most common herbs in the Wizarding World, which might be dangerous if not handled properly, but definitely not dangerous on their own (with a few exceptions).
Alihotsy
This looks like an ordinary herb, with no special characterizations. However, consuming the leaves of Alihotsy in anyway can induce hysteria at all living beings. What makes it very harmful is that the effect can last for quite long unless an antidote is used. The reversing effect can be achieved only with "Glumbumble Leaves".
Aloe Vera
Aloe Vera doesn't really possess any special magical properties, but it still finds its use in the Wizarding World. It's a stemless herb with serrated leaves, that can be found everywhere in the world. The specialty of the herb lies in the fact that it's very fresh and juicy, and it soothes the human skin. Because of that, this herb is used for the creation of various deodorants, perfumes, body lotions, etc. It became famous for its use in "Lowdour", a magical brand of deodorant without a fragrance.
Bouncing Bulb
As you might notice from the "bouncing" in the name, this herb is actually capable of moving. Its stem looks like a purple blob, or bulb, if you must, and it has a couple of long thin leaves sprouting from the top of its head. When young, a Bouncing Bulb is quite small and harmless, but as they grow up they can become enormous (with the size of a doorway even), and are very difficult to handle.
What makes them dangerous in general is that they aren't really peaceful, but quite aggressive. They're protective both of their territory and their offspring, so don't make them feel threatened or you might not get out alive unless you know you way with a wand, as a Knockback Jinx and an Incendio Charm can help you deal with a bulb.
Bubotuber
This herb has two different parts, one is underneath the ground and the other is above the ground. The second part, which is visible to us, resembles a thick and black slug with huge dimensions, and it has the power to squirm by its will. What makes this a harmful herb is that it spits out yellowish-green pus with the scent of petrol whenever someone gets nearby, and the undiluted Bubotuber pus can really harm your skin in various unappealing ways.
However, this herb also has pus in the protrusions that cover its body, and if squeezed out and processed properly it has the counter effect - it's helpful for your skin, especially for curing acne. This healing effect of the Bubotuber pus was discovered by Sacharissa Tugwood (1874 - 1966), who also invented some of the earliest Beautifying Potions in the Wizarding World. Nowadays, her gravestone, which is probably in Scotland as that's where Bubotuber is endemic to, reads "Thanks to Sacharissa Tugwood, the world is a more beautiful place."
Cocoa Bean
Cocoa Bean isn't actually a herb with magical properties, it's just the seed of the cocoa tree. However, they are quite commonly used in the Wizarding World, specifically for sweets, such as Treacle fudge. This fudge can be bought at Hogsmeade's sweets-shop, Honeydukes, though there are any home-made versions as well. Rubeus Hagrid for once, has always made them at home, and has grown all the ingredients in his garden.
Daisy
The Daisy is a wildflower common to both Muggle and Wizarding Worlds, but it finds more use in the latter, and even though it is found only in Europe, it is used all around the world. The flowers, which can be yellow or white in color, don't have much use. The roots on the other hand, are minced and used in the "Shrinking Solution", a potion that makes the user shrink in size or decrease in age. And they are also used for the creation of alcoholic beverages, the most famous from which is the "Daisyroot Draught" (not really a draught!).
Devil's Snare
This is probably one of the most dangerous herbs in the Wizarding World, and definitely the most dangerous one that we will study in this Greenhouse. The name comes from the fact that it has the ability to wrap around its victim and constrict over time with such strength that it could easily choke people and break their bones with its tendrils and vines. To make things worse, if you struggle, it will apply greater force and strangle you quicker, though if you stay calm and relaxed it will attack at a slower pace. It's quite easy to deal with it with a single fire or light charm of any type, but unfortunately it binds anyone it comes in touch with, so if you want to be saved, it will have to be someone who is not trapped by it as well.
This is a very rare herb, as it is endemic only to Scotland, and it also occupies only dark and damp places, but it is the most common assassin in the Wizarding World. Rumors have it that it's related to the "Flitterbloom" but there's honestly no real proof for that.
Dirigible Plum
This is actually a fruit bush/tree that resembles something between an orange and a radish. Its fruits grow upside-down and it's found only in England. Certain people believe that it enhances the ability of accepting the extraordinary at human beings, but that's just an assumption/belief.
Fanged Geranium
This is another flower from the Wizarding world. It really doesn't differ a lot from the usual flowers that we know, the only difference is the fact that the Fanged Geranium has teeth (sharp ones!) and they can be very dangerous if people don't pay attention (constant vigilance!) and don't know how to protect themselves. The flowers aren't poisonous, but they can literally eat a human being bite-by-bite.
Fire Seed Bush
As you can notice from the name, this herb is actually set on fire, and it can only live if it stays on fire. It's said that it is endemic only to Britain, though it has been noticed around the world as well (it prefers closed areas, such as caves). It looks like a flaming red spikey bush and it is extremely hot, though it is not really dangerous unless you yourself rush into it and get burned.
If you know your way with charms, you can hit the bush with a freezing charm, which would result in the bush dropping "Fire Seeds", a not-so-common potion ingredient. However, in order to collect the seeds, one first must wait for them to cool down or cast another freezing charm to achieve the same for a shorter time. These seeds can later be used even for maintaining a high temperature (useful when breeding creatures like dragons).
Flitterbloom
The Flitterbloom is almost identical to the "Devil's Snare" discussed above. The only difference is that this one is harmless and wouldn't hurt anyone, otherwise they look the same (long swaying tentacles, vines, tendrils, etc. you can easily mix the two up). Please go back and read about that herb if you haven't done so yet. And always be careful around herbs of this type, because you may think it's a Flitterbloom but it might end up being a Devil's Snare.
Floo
A simple branching herb whose flowers can be used for extracting "Floo Powder", an essential item for traveling from one place to another in the Wizarding World, especially when doing it regularly and trying to hide it from the Muggles. However, not many examples of this herb are left, the Ministry of Magic is currently trying to control all the Floo Powder connections and is the only producer of this powder.
Flutterby Bush
This bush shakes and flutters even when there is no wind around. It looks much prettier than the common bushes, because it has pretty leaves and a nice odor, but it's not of much unless you need a plant for decoration purposes. It is believed that it can adapt its scent to attract the unwary, once a century, but I personally do not believe in that.
Fluxweed
Fluxweed is actually a mint herb. Its more important use is for the "Polyjuice Potion", a potion that lets you take the look of someone else for a while, but in order for to have the effect for this potion, Fluxweed must be picked at full moon (you need exactly 16 scruples).
Germander
This is another herb without any magical properties at all. However, just like the "Cocoa Beans" that we talked about earlier, it is still commonly used in the Wizarding World because of its use in sweets, specifically the "Treacle Fudge" (at least the recipe by Rubeus Hagrid).
Gillyweed
Gillyweed is a quite known herb in the Wizarding World, even though it is only endemic to the Mediterranean Sea. It lower part looks like a bunch of slimy rat tails with a specific color, something gray-greenish, and the upper part looks just like normal green leaves, medium sized and with no special characteristics.
When witches and wizards consume this herb, they grow gills and webbing between their fingers and toes, which would help them move faster underwater, almost fish-like. This effect lasts about an hour, though it is unknown if it has a different duration in fresh and salt water (you can check that out yourselves). Furthermore, gillyweed is used for making drinks such as "Gillywater", which I personally haven't tried and can't tell you what it tastes like.
Ginger
This is another non-magical herb, though it is considered as a spice with a very strong flavor and scent so it serves a wide culinary purpose. Just like the muggles, we wizards and witches also have sweets created with Ginger, such as "Ginger Newts" (biscuits). The root of this herb is also used in potion-making. For example, it is one of the required ingredients for the "Wit-Sharpening Potion" which helps the user think more clearly.
Certain wizards and witches believe that the Ginger also has minor healing powers, and use it in the medicine against cold, flu, stomach pains, etc.
Goosegrass
Goosegrass is also known as "Cleavers", "Stickyweed", "Catchweed", and many more similar names. It can reach a height of up to 2 meters, it has simple leaves, both the stem and the leaves are covered with hairs, and its flowers are super tiny and their color can vary from white to green. However, when the herb becomes dry it changes its color to yellow-ish, and this is when it can be picked up for potion-making purposes.
It is endemic only to North America, and is very rare, so it holds a high price in the apothecaries, though its use in potions is unknown to me (make a note to bug your Potions teacher!).
Gravity-Resistant Tree
Yes, there are things like that in the Wizarding World as well. It looks like something between a bush and a tree, just smaller compared to actual trees, and it floats in air. This tree has no special characteristics, it's only there to make a Wizarding Garden look prettier.
Gurdyroot
This herb looks like a green onion, and it smells and tastes even worse than an onion (yep it's horrid), yet it can be found all around the world but obviously not anywhere near inhabited places. A proof that it has a horrible taste is the "Gurdyroot Infusion" drink which despite its lovely purple color has a disgusting taste. Certain wizards and witches believe that this herb is good for warding off various "Plimpies" (small and weird fish creatures).
That was a lot for one lesson though, give yourself a small, well deserved break, and then feel free to proceed to the the Assignment.
Credits
Graphics References:
Banner made by the lovely Bianca Delacroix!
Plants and plant product graphics in the gallery bellow are copyright of Pottermore.
Lesson References:
Harry Potter Wikia
HP Lexicon
Pottermore
Wikipedia