Sowing

Key takeaways

Sowing belongs to science; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Sowing to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Sowing from memory before moving on to harder problems.

Reference excerpt

Sowing is the process of planting seeds. An area that has had seeds planted in it will be described as a sowed or sown area.

Plants which are usually sown Among the major field crops, oats, wheat, and rye are sown, grasses and legumes are seeded and maize and soybeans are planted. In planting, wider rows (generally 75 cm (30 in) or more) are used, and the intent is to have precise; even spacing between individual seeds in the row, various mechanisms have been devised to count out individual seeds at exact intervals.

Depth of sowing

In sowing, little if any soil is placed over the seeds, as seeds can be generally sown into the soil by maintaining a planting depth of about 2-3 times the size of the seed.

Sowing types and patterns For hand sowing, several sowing types exist; these include:

Flat sowing Ridge sowing Wide bed sowing Several patterns for sowing may be used together with these types; these include:

Rows that are indented at the even rows (so that the seeds are placed in a crossed pattern). This method is much better, as more light may fall on the seedlings as they come out. Symmetrical grid pattern – using the quincunx pattern described in The Garden of Cyrus

Types of sowing

Hand sowing Hand sowing or (planting) is the process of casting handfuls of seed over prepared ground: broadcasting, that is, broadcast seeding (from which the technological term is derived). Usually, a drag or harrow is employed to incorporate the seed into the soil. Though labor-intensive for any but small areas, this method is still used in some situations. Practice is required to sow evenly and at the desired rate. A hand seeder can be used for sowing, though it is less of a help than it is for the smaller seeds of grasses and legumes.

Hand sowing may be combined with pre-sowing in seed trays. This allows the plants to come to strength indoors during cold periods (e.g. spring in temperate countries).

Seed drill In agriculture, most seed is now sown using a seed drill, which offers the best precision; seed is sown evenly and at the desired rate. The drill also places the seed at a measured distance below the soil, so that less seed is required. The standard design uses a fluted feed metering system, which is volumetric in nature; individual seeds are not counted. Rows are typically about 10–30 cm apart, depending on the crop species and growing conditions. Several row opener types are used depending on soil type and local tradition. Grain drills are most often drawn by tractors, but can also be pulled by horses. Pickup trucks are sometimes used, since little draft is required. A seed rate of about 100 kg of seed per hectare (2 bushels per acre) is typical, though rates vary considerably depending on crop species, soil conditions, and farmer's preference. Excessive rates can cause the crop to lodge, while too thin a rate will result in poor utilisation of the land, competition with weeds and a reduction in the yield.

Open field

Open-field planting refers to the form of sowing used historically in the agricultural context whereby fields are prepared generically and left open, as the name suggests, before being sown directly with seed. The seed is frequently left uncovered at the surface of the soil before germinating and therefore exposed to the prevailing climate and conditions like storms etc. This is in contrast to the seedbed method used more commonly in domestic gardening or more specific (modern) agricultural scenarios where the seed is applied beneath the soil surface and monitored and manually tended frequently to ensure more successful growth rates and better yields.

Pre-treatment of seed and soil before sowing

Before sowing, certain seeds first require a treatment prior to the sowing process. This treatment may be seed scarification, stratification, seed soaking or seed cleaning with cold (or medium hot) water. Seed soaking is generally done by placing seeds in medium hot water for at least 24 to up to 48 hours Seed cleaning is done especially with fruit, as the flesh of the fruit around the seed can quickly become prone to attack from insects or plagues. Seed washing is generally done by submerging cleansed seeds 20 minutes in 50 degree Celsius water. This (rather hot than moderately hot) water kills any organisms that may have survived on the skin of a seed. Especially with easily infected tropical fruit such as lychees and rambutans, seed washing with high-temperature water is vital. In addition to the mentioned seed pretreatments, seed germination is also assisted when a disease-free soil is used. Especially when trying to germinate difficult seed (e.g. certain tropical fruit), prior treatment of the soil (along with the usage of the most suitable soil; e.g. potting soil, prepared soil or other substrates) is vital. The two most used soil treatments are pasteurisation and sterilisation. Depending on the necessity, pasteurisation is to be preferred as this does not kill all organisms. Sterilisation can be done when trying to grow truly difficult crops. To pasteurise the soil, the soil is heated for 15 minutes in an oven of 120 °C.

Illustrations

Worked examples

Example 1 — a first encounter with Sowing

Start with the simplest possible case. Write down what Sowing claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In science, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Sowing before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Sowing ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Sowing

In research: Sowing appears in science research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Sowing in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Sowing is common in secondary-school and first-year university syllabi. It links to neighbouring topics Agricultural practices, Agronomy, Habitat management equipment and methods, so understanding it makes those chapters shorter.
In everyday life: Look for Sowing outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

How to study Sowing in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Sowing means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Sowing out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Sowing in simple terms?

Sowing is the process of planting seeds. An area that has had seeds planted in it will be described as a sowed or sown area.

Why does Sowing matter?

Because it connects several science ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Sowing?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Sowing.