HERB-201 Lessons

Year Two, Lesson Eight
Hands-on Herbology

Introduction
Welcome back to round two of water plants, class! This week’s topic is the saltwater cousins of the plants we looked at last week. There are thousands of verdant denizens under the sea, though they may have escaped your notice as they are not as common a sight as a beautiful red rose or a creeping vine at Hogwarts. Since there are so many, and sadly we can cover so few, our focus will be on plants that grow (or can grow) in shallower areas, as they don’t need enormous tanks. Your individual plots in the greenhouses don’t have enough room for ground to ceiling tanks like we have in Greenhouse Four, after all! In addition, we need to touch on some specifics with regards to growing saltwater plants, as well as a topic we overlooked in the plant life cycle: repotting.

Salt Specifics
With Hogwarts being rather far from any ocean or sea, you may be wondering how you are expected to grow saltwater plants. The answer is simple: add salt! While technically you can obtain salt from the castle rather easily, I’d prefer you didn’t plunder the kitchens for your greenhouse needs. With our various potions, lotions, insecticides, and more, I also keep innocuous bags of salt. The proper ratio for seawater is one ounce of salt per every three gallons (35 grams per liter), so if you are attempting to fill a 100 gallon tank, you will need 33.3 ounces, or 2.1 pounds, of salt. Didn’t think you were going to have to do math in Herbology class, eh? I assure you, these greenhouses are full of surprises. Before we move on from ratios and math -- and salinity -- if your plant needs brackish water (slightly salty water), but not quite the full seawater effect, then the ratio is adjusted to only 0.55 ounces of salt per three gallons (20 grams per liter). Brackish water is a little saltier than freshwater, but not as salty as actual seawater, and is found in locations where the two mix, such as deltas, estuaries, and certain swamps.

Keeping saltwater plants in a greenhouse is often a little more difficult than freshwater plants, as many of those require only shallow water. Saltwater plants that grow in the ocean, on the other hand, typically grow far down on the ocean floor. Because of this, many common seagreens are all but impossible -- or at the very least inconvenient -- to grow in captivity due to the space they require. There are still some saltwater plants we can cover today, though, that do not need miles and miles of space.

At the Bottom of the Deep, Blue Sea
As you may be able to tell, I find water plants to be some of the most interesting greens. What a world of variety and hidden secrets! If you are anything like me, the handful of examples we are covering is simply not enough. So, should you desire to learn more about magical water plants -- saltwater ones especially -- Magical Water Plants of the Mediterranean by Hadrian Whittle is an excellent resource right in our own library. The Mediterranean is a very populous place for magical water plants and is absolutely teeming with prime specimens of your common saltwater plants as well as unique aquatic oddities not found anywhere else. This is why many aspiring herbologists study there, as was the case with Mr. Whittle. He also has a secondary volume, Magical Water Plants of the Highland Lochs, though shorter, which pertains specifically to freshwater plants in his native region if you are looking for an extension of our topic from last week instead. Enough talk of books, though! While books are a boon, there’s nothing quite like diving right into the thick of things and experiencing them for yourself.

Manatee Grass
This thin, stringy grass is native to warm, shallow locales, such as the Gulf of Mexico or the Caribbean Sea. Fortunately, these temperatures are mimicked well in greenhouses. For best results, grow in roughly five to ten feet of clear water that gets the rough equivalent of full sun. Manatee grass will grow with less sunlight, but these are the best conditions for rapid growth. To plant, simply insert the seeds roughly an inch into sediment at the bottom of the tank. Obviously, this will be well out of your reach, and I don’t particularly want you sloshing around in school-issued tanks. Therefore, in order to plant a seed at this depth, you will need to take out your wands. The Propulsion Charm is a very easily adapted spell and, in this case, is going to be used to propel your tiny seeds into the sediment in the bottom of the tank. I will include the spell’s details shortly, but while we are on the topic of soil, you should ensure that your sediment and soil at the bottom of the tank has an alkaline pH somewhere around 8.0 to 8.5.

                       
This watery plant, syringodium filiforme, should grow rather rapidly, reaching a maximum height of 20 inches. It can be harvested at any point, and shears are commonly used to do this. Apart from its popularity among manatees -- hence its name -- this seagrass can be dried and ground into a powder and used in potions to sterilize wounds. This practice is particularly prevalent in the areas where it is native. In addition, it can be used fresh in Double-Jointed Draughts.

Neptune Grass
Also known by its less romantic common name of Mediterranean tapeweed, this plant is one of the many that Hadrian Whittle covers in his book. However, we would call this a non-magical plant. I see some confused looks on your faces. In the day and age when Mr. Whittle was traversing the Mediterranean to write his book, the distinction between magical and non-magical plants was much more vague. At the time, a plant was considered magical if it had a magical use. This meant if it could be used in potions, or even if it was consumed by a magical creature, it qualified as magical. Since then, more and more properties of increasingly common plants have been discovered, causing herbologists and theoreticians alike to rethink the previous definition as to what made a plant “magical,” and the definition we use today was settled on.

In any case, Neptune grass, or Posidonia oceanica, grows in shallow areas of the Mediterranean, though it can flourish in much deeper valleys on the seafloor as long as the water is clear enough to allow for light to reach the plant’s leaves and give it at least three hours of sunlight a day (or partial shade). The total range is anywhere from roughly three to 115 feet in depth! It has ribbon-like, bright green leaves that float along the water and can easily get tangled up, forming balls that wash up on the shore. The entire plant will grow as much as it is allowed, depending on age and room available. The longest recorded specimens come in at several hundred feet, but would grow on a much smaller scale in a greenhouse.

The plant is used in fantastically complicated potions to promote longevity, but also enjoys more common use in various beauty serums, and even aging potions (though not the one used commonly in the UK). This plant can be used while fresh or while dried, though many apothecaries and potioneers swear by the fresh stuff!

Gremathea
Now let’s take a look at a plant a little closer to home: Gremathea. This magical purple seaweed is native to essentially all coastal regions of both Ireland and England. It is happiest in the shallows -- roughly just a handful of feet to as much as fifteen feet in depth -- and grows close to the shore. It therefore needs to be carefully managed, for reasons that will be explained shortly. The distinctive purple clumps grow well in slightly acidic soil (6.0 - 6.5), which is native to most parts of Ireland and England. This plant does well in partial shade or partial sun, though the time of day really does not matter. It can certainly take more sunlight than that, but this is not strictly necessary.

Now, to explain just why this plant is magical and needs such looking after: it is devilishly sticky! Boats have been known to brush their hulls against clusters of the magical plant and accidentally anchor themselves to the area (or worse, tear holes in their hull as part of it is left behind, still stuck to the Gremathea). It is also a hazard for swimmers, divers, and general holiday-makers, as it can adhere to the skin and prove possible to remove with loss of limb unless there is prompt intervention from a healer. Therefore, to harvest, you will need to take similar precautions as when harvesting Puffapods -- store the collected specimens with a Repelling Charm on both the plant and the container. It is also absolutely crucial to wear your dragonhide gloves!

Due to this, Ascophyllum lentus is highly regulated and trimmed so as not to spread too far into boat lanes or onto public beaches. However, don’t think the plant is only a nuisance! In addition to pairing very well with stilton cheese and crusty bread when cooked, Gremathea is also used in nest-making by various creatures. There are also a number of medicinal and potion-making uses, such as in Odorous Concoctions and Shouting Solutions, as well as the patented Hangnail Healer.

Gillyweed
Before we end our look at saltwater plans, we really must take a look at Giliac quatus, otherwise known as Gillyweed. This plant is another that is native to the Mediterranean and grows in slimy clumps in tide pools along the shore. It is very adaptable, growing in shade, full sun, and anywhere in between. In fact, it will even grow in freshwater, as we will discuss in a moment. It prefers a rather alkaline soil base, from around 7.8 to 8.4, and will grow up to ten inches in length. Its greyish-silver (or occasionally green) leaves can be harvested at any time. You may need to repot it rather frequently, though, as its roots grow very rapidly!

As far as the effects and properties, the name says it all. Or, well, it at least gives you a hint. Gillyweed grants the consumer roughly an hour of easy breathing underwater via gills along with some modest side-effects, including webbed hands and feet. The hour of breathing underwater is actually not so straightforward, however. Various studies have been conducted that find the average length of efficacy in freshwater is roughly 45 minutes, whereas the efficacy in saltwater averages around an hour and a half (with the longest recorded time being over two hours). However, these findings are slightly contentious, as some herbologists have hypothesized that the disparity between the two is due to the existence of different strains of Gillyweed or different potencies for other reasons, rather than an overall difference based on water content. More study is needed to be sure!

It also has less famous uses. It makes a lovely culinary addition, both in the form of salads and mixed greens as well as in Gillywater. Just be sure the dish you’re eating doesn’t contain too much pure Gillyweed. I imagine you wouldn’t want to sprout gills in the middle of the Three Broomsticks! Don’t be too concerned, though. While the amount varies from person to person, roughly one heaping handful in a sitting is the limit. Current restaurants perfected their recipes long ago, though it doesn’t hurt to ask if you are particularly susceptible. Finally, while not well-known, the roots of this plant can be used to alleviate headaches.

Closing
With that, our second to last lesson of the year draws to a close. We are nearing the end of your practical year, though, as mentioned before, that doesn’t mean we won’t be taking a hands-on approach to Herbology in the future! Next lesson, we will just have a bit of fun with plants and spells -- no mess, no stress -- before concluding the year with your final examinations. I hope you haven’t been forgetting to tend to your dandelions despite the fact that we’ve been looking at nocturnal and water plants these last few weeks. Keep up the good work and I will see you soon.

As a note, sadly, there are no actual books by Hadrian Whittle in the HiH library

Original lesson written by Professor Venita Wessex
Additional portions written by Professor Lily Tudor
Image credits here, here, here, here, and here