Gardening Notes

Sometimes when I’m burned out from writing final exam questions and having fever dreams about the same, I start to think about everything in exam question format. This is an effort to document that, for gardening-related questions. I offered these as examples of the format of questions I might ask students for my Fall 2020 Information Security Management class. They’re sloppy, they’re unsourced, and they’re probably full of inaccuracies, but that’s science! (⌐■_■) Submit a pull request to fix!

Quiz question that may appear on the exam because I think it is just so interesting – why do plants – tree branches, etc – grow upwards, but only if exposed to the sun? For example, a branch shaded by upper branches would grow laterally until it came out from under shade, after which it would grow upwards. Why?

I don’t remember all the vocabulary, but there is a growth ring around every growing branch. The material in that ring can be affected by two main factors - (1) gravity, and (2) sunburn death. For a laterally growing branch exposed to the sun, both factors would cause a higher concentration of growth material on the bottom of the ring than on the top, which would cause the bottom to curve upward because of faster growth. Once the branch is growing straight up, gravity is no longer a differential factor, and sun is equal. Tada!

Second, why are some trees shaped like cones? Consider a spruce, Christmas tree shape. Its branches would be triangularly-shaped – narrowest always at the growing tip, but wide further down the branch away from the tip. The tree itself would be wider at the base than at the top.

The growing tip contains a hormone that suppresses lateral growth, but only the tip has that. The further away a branch gets from the tip, then the further away it gets from hormone growth suppression, and therefore can grow more.

It is commonly known that lightning storms lead to greener grass, assuming it also rains. Why?

There’s a ton of nitrogen in the air we breathe, and plants love nitrogen – nitrates/nitrogen is the number one component of most plant fertilizers like Miracle-Gro. But nitrogen in the atmosphere, two nitrogen molecules bonded together, nitrogen dioxide – is not usable by plants. But lightning explodes the bond of nitrogen dioxide (chemical change) which makes the free nitrogen molecules free to bond with oxygen, which it does, which then can dissolve in water, which then gets rained down, which is essentially liquid fertilizer.

What do you call it when succulents get abused at places like Walmart, home depot, etc, and they drop their leaves on the floor, then people like me check the floors and put the fallen leaves in our pockets (with the blessing of store employees who would have swept them up and thrown them away anyway), then take them home and neglect them further, until in desperation they put out roots in a last ditch attempt at survival, then we plant them in animal shaped containers?

Proplifting. Propagation shoplifting.

When is the proper time (month) to start pepper plants from seed, to have fruit born in the proper season?

Like January!

If you enjoyed playing with legos as a kid, then look into “drip irrigation” for gardening

(This is not a quiz question)

Compost piles should be turned often. If they are not turned, then the contents inside will rot. Rotting is not composting. If they’re turned, then composting may happen. Wtf?

Composting relies on aerobic bacteria – bacteria that breathes, needs oxygen. These bacteria do not stink. Rotting, on the other hand, is an anaerobic process– does not require oxygen. I’m fuzzy on this but I think there’s also bacteria involved that don’t need oxygen. This kind smells something fierce. Don’t turn, then you’re welcoming anaerobic bacteria.

I told the students:

btw, questions in the style like the above are kinds I might actually write on the exam. A statement, followed by a question, and then “select all that apply” with a list of questions that might or might not explain or support the statement.

Like for the lightning storm one, One of the MC options might have said basically what I said in the threaded response, except calling it a state change instead of a chemical change. Assuming that understanding state vs chemical change were a learning objective of the course

that’s what I mean by conceptual understanding

and another option might have said something besides nitrogen, or something about the manner in which it becomes available to plants, or another option might have refuted the statement with a correction

On January 20th, the next semester with the same grad students as the previous semester, it happened again. I got burned out from creating assignments.

Welcome to another class session of Gardening with Me – a class focused on giving you cocktail-party-level mastery of gardening

In y’olden days, American settlers needed cash. What they had was land, and the land had lots of trees. They got cash by clearing out the trees, and burning it down for the ashes. The ashes contain potash, which can be used to make glass and soap. Settlers could basically clear their land for zero-sum cost – it cost about as much to hire a laborer to clear the land as the income they would get from selling the ashes.

while sitting around a backyard firepit, i had an offhand curiosity in knowing how I would go from the campfire ashes to DIY soap. Turns out that bloggers on the internet are very confused on the topic.

On their video blogs and etsy whatever crap shows, they bring out a bottle of sodium hydroxide crystals – lye – aka drain cleaner, roadkill decomposer. They don their fancy etsy crap rubber gloves and goggles. then they offhand say something like this: “lye is used to make soap. Lye is also called ‘potash’. You can also get lye from campfire ashes, because you get potash from campfire ashes.”

Exam question – what is wrong with the above statement?

Answer – and this is a doozy, and I’m still weak on my understanding of this – there are several different chemistry “kinds” of potash. e.g., potassium hydroxide, potassium carbonate.

something that is a “lye” has to be a hydroxide. but potassium hydroxide does not come from plant (wood) ashes – carbonates do. but potassium carbonate (not a lye) can be used to make soap and glass, just as potassium hydroxide (a lye) can.

90% of wood ash is chalk and sand. You can convert potassium carbonate into potassium hydroxide by baking the chalk and sand at 1000 degrees celcius, which, when combined with water, gives you slated lime. mix the slated lime with a carbonate, and you get a hydroxide. But dag nabbit, none of those bloggers are doing crazy crap like that. they just leach the ashes by adding in a bunch of water, which sucks the potash out of the ashes, and then the potash solution drips down into another bucket, and they call this “lye water.” That it is not!

Another exam question: Blogs will also say you need to burn hardwood, not softwood, to get the potash. Why?

A: because hardwoods usually have higher concentrations of potassium carbonate, whereas softwoods have higher concentrations of sodium carbonate. The latter is good for liquid soaps, the former for bar soaps.


Q: what do you get when you electrocute potash?

A: potassium. In fact, this is how potassium was originally discovered – electrolysis of potassium carbonate (potash)

Q: what do plants use potassium for?

A: I don’t remember, but a lot of things.

Q: bananas have a lot of potassium, can you stick a banana in the ground as a source of potassium for plants?

A: no.

Potassium is radioactive, and therefore bananas are radioactive.

Plants need a salt form of potassium in order to have access to it. Read – a water-soluble form of potassium. Things like miracle-gro are so dang expensive because they make the essentials– nitrogen, phosphorous, and potassium– available in a water-soluble form

Q: how do plants get nutrients,

A: tiny tiny hairs on the tips of roots wick up the water in the soil, along with its nutrients

What do the rows in the periodic table of elements represent? (edited)

Shape and number of available orbits of electrons. The further right you go in a row, the more the next unfilled orbit gets… filled. Once they’re all full, start a new row.

I might be wrong on that in some way. But that one took me a while to figure out.