It’s one thing to think about the cycle of life in terms of seasons. In northern climates, winter is a time of snow cover and cold.
A few plants have specialized to live in these climates, but most begin life in the spring or summer and die (or go dormant) in the autumn. In this article, we answer how that works and dive into the life cycle of a plant.
Looking for more planty knowledge? Look through HerbSpeak’s latest botany articles.
““Seeds generally are the basis for everything. Not only what we eat, but what we wear, nature all about us.””
Other plants may be clones from the parent plant as leaves or stems with the right cells break off and take root, or if the leaves bend into the earth and re-root to create a new connected plant. This is known as vegetative reproduction.
There are other types of plant reproduction as well, however, for the sake of simplicity we will be discussing seed reproduction.
What Are the Stages of Plant Growth?
The basic stages of plant growth are germination, development, fruit and seed, and decay. These four stages are the most basic that you can get. For a more complete view, you will see 7 stages illustrated in the sections below.
First, let’s address the fact that not every plant is the same. Plants have a wide range of growth habits depending on their structure, evolution, and native habitat. What this means is that basic stages of the life cycle of a plant will be the same, but some plants may take more time, or have additional steps.
For general botany, however, these steps are comprehensive enough to give us an overview of plant life.
For example, evergreens don’t go through a full dormancy period, though their photosynthetic processes do slow down.
If it gets cold enough, they may begin to evacuate water from their cells to prevent it from bursting, but for typical cold weather, these plants have developed a sort of anti-freeze from the sugars and proteins they produce throughout the growing season.
Likewise, you may be familiar with perennials if you have a small garden.
These plants are confusing to many people at first, because they don’t go through a full life cycle in a single year – the tuber, bulb, or root, stays active and dormant underground, ready to re-sprout the following growing season.
They will eventually, however, outlive their genetic potential and live out their full life cycle.
1. Seed Germination
When a fruit is fertilized and the seeds inside are dispersed, they land with only a chance of germinating. When the conditions are right, however, the seed can begin to germinate. Each species has different requirements. Some seeds require scratching to break down the seed coat, while others require a certain amount of moisture.
This means that the embryo (baby plant) inside the seed shell breaks through the shell and is starting its journey into the world. As the seed breaks through the surface of the shell, the roots begin growing down, and the stem begins growing up.
2. Seedling Development
As the seedling solidifies its position in the world, anchoring its roots in the soil, it is using energy that is stored inside the seed in a small packet called the endosperm.
Fun fact: This packet of nutrients meant to help the plant grow is why seeds are so nutritious and healthy for you to eat!*
*in non-toxic, edible seeds typically served for culinary purposes
The seedling uses this store of nutrients to develop. When it is ready to start manufacturing its own energy, it develops what is known as ‘true leaves’. These leaves are fully functional, allowing it to generate new energy for further development.
3. Plant Growth
If the plant was lucky enough to land in a place that is compatible for growth, it continues to grow new parts until it has enough leaves.
With enough leaves, it can develop more roots, gaining access to water and nutrients from the soil, and longer stems to reach towards the sun.
4. Plant Maturation
As the plant matures, it has developed a functional and stable support system that helps it get nutrients, sunlight, and water. (That’s the leaves and roots!)
The plant is now generating enough energy to develop flowers (in the case of flowering plants, also known as angiosperms) which allows it to attract pollinators. Pollinators come in a wide range of shapes and sizes, from ants to birds and everything in between.
5. Pollination and Fertilization
Fertilization is an essential part of a plant’s life, allowing it to reproduce. This can be done with help from pollinators, but many plants have a fail-safe where they can pollinate themselves.
Not every plant can do this, however, and pollination between two distinct plants is important to keep its offspring’s genetics varied.
Once the plant is pollinated, the plant undergoes changes to begin developing fruit. In flowers, a fertilization tube grows down into the ovary of the plant, completing the fertilization process.
6. Bearing Fruit and Seed
Once fertilized, the ovary swells and develops into fruit. As the fruit develops, new seeds develop within this fruit.
In this case, ‘fruits’ is being used in the botanical sense, meaning the fertilized ovary of the plant rather than exclusively a culinary fruit you might eat.
Fun fact: This means a botanical fruit can be anything from an apple to a hazelnut.
Depending on the plant, these seeds are then dispersed with help from animals which eat or carry off the seed, or environmental factors like wind and rain.
7. Dormancy and Decay
Once the plant has dispersed its seeds, it is ready to go into the next stage of life. In some plants, this means it begins to wither as colder weather comes in, and it begins to decay.
This decay is excellent for soil health, promoting healthy food for soil workers like worms and beetles. This means the soil becomes richer, more nutritious, and better aerated for future generations.
In some plants, however, they live for multiple years. In this case, they go into a dormancy period. Above ground, the plant may wither and appear dead, however, the plant is just storing its energy in the root or bulb below ground. The above-ground parts that wither are still broken down to provide nutrients to the soil.
Full Life Cycle Stages of a Plant
Let’s recap with a question.
Without going back to look, what is something a plant needs to do before it completes its life cycle?
Below, we review the life cycle of a plant as an overview. The more you dive into a specific plant species, the more detailed the image becomes. Environmental and genetic factors do play into a how any individual plant lives out its life cycle.
Let’s paint an example of how environmental and genetic factors can play into a plant’s life cycle. Let’s say a plant is doused with a chemical that affects it on a genetic level. If the genetic trigger for fruiting is turned off, the plant will not begin fertilization, fruiting, or going to seed. This means that it will skip this step entirely until the genetic factor is turned back on, or the plant expires.
Just like how plants can tell what season they are in, they can tell when it is time to fruit or begin maturing. For example, winter wheat is a common agricultural crop. This wheat requires a cold period to trigger reproduction, which means it does not turn into a harvestable grain, nor does it produce a second crop.
Once the plant senses that cold period, however, it will begin producing seed in the following weeks. This process is known as vernalization.
- Jennifer Duggan, Inside the ‘Doomsday’ Vault, https://time.com/doomsday-vault/