Photos & differences between annual, perennial & biennial plants (2024)

One of the most useful things I ever learned about plants is how to observe the stages of plant growth.

All plants follow the same basic patterns of growth on their way to maturity and this gives us a better way to identify and understand those plants more deeply.

The simplest way to describe plant growth is with 4 stages:

1. Germination is when the seed first becomes active and starts the whole process of plant growth. Germination is triggered by a specific set of soil, moisture & temperature conditions.
2. Leafy growth – The plant will go through a period of leafy growth to build a strong root system and develop it’s capacity for harvesting energy from the sun. Many plants are at their most difficult to identify at this stage.
3. Flowering happens once the plant is strong enough and has the optimal conditions to bloom. The plant produces colorful blossoms to attract bees & other pollinating insects, or to spread pollen on the wind.
4. Seed distribution is the ultimate goal of every plant. This is what moves their species forward and gradually evolves new genetic diversity.

Knowing these stages gives you a much more intuitive ability to understand plants just by looking at simple patterns that all plants share in common. It’s so simple even a child can learn what to look for.

The cool thing is you don’t even need to know the identity of a plant in order to know what stage of growth that plant is in. And knowing these stages consequently makes plants easier to identify!

Most plants are easiest to identify at specific stages of their development, or have edible/medicinal qualities that require a specific stage for harvesting.

Depending on your personal goals & interests with learning about plants, you may want to use more stages, and different types of plants may require more stages to describe their complete lifecycle.

How Many Stages of Plant Growth Are There?

The number of stages used to describe plant growth typically ranges between 3 and 6, however it’s possible to classify as many as 8 or more stages of plant growth.

How much precision you need all just depends on what your goals are when it comes to plants.Many plants have a dormancy stage that simply isn’t relevant to annual crop farmers so it gets left out.

For the purpose of completeness, here’s an 8 stage model of plant growth to cover all the bases:

8 Stages of Plant Growth:

1. Germination
2. Leafy Growth
3. Budding
4. Flowering & pollination
5. Fruit & seed formation
6. Ripe Harvest/Fruit & seed dispersal
7. Hardening/Die back
8. Dormancy

Some plants can go through each of these stages in a matter of weeks, while others take multiple years to complete the entire cycle.

These stages are all fairly simple to understand, with the possible exception of stage 7 – Hardening/Die Back. This is what happens after the seeds are distributed.

The plant will either die (in the case of annual plants), or in the case of perennial/biennial plants, they move their energy from the leaves down into the roots to survive the winter. Shrubby perennials also put a lot of energy into hardening their tender new growth into wood at this time.

Many plant growth models that focus on food production assume that the final stage of growth is harvesting (which isn’t technically true). In this case, they might only use 5 stages:

5 Stages of Plant Growth:

1. Germination
2. Leafy Growth
3. Budding
4. Flower
5. Harvest

And along these same lines – Some crops also have very delicate needs in the early stages of their development, so food producers might include an extra seedling stage, leaving us with 6 stages:

6 Stages of Plant Growth:

1. Germination
2. Seedling
3. Leafy Growth
4. Budding
5. Flower
6. Harvest

It’s entirely up to you to decide how you want to section up these stages. In reality, these differences are somewhat arbitrary and it really just depends on what your goals are.

The important thing is knowing how to observe these stages with your own eyes, so let’s look at some examples showing how to apply these plant growth stages to several different types of plants.

Growth Stages In Annual Plants

Annuals are plants that complete their entire life cycle in a single year. They grow very fast because they need to germinate, grow & spread viable seed in a very short period of time.

Some common examples of annual plants include many garden vegetables like lettuce or spinach.

Germination

First the seed will germinate and a new plant is born. When conditions are right, annual plants germinate very quickly, typically within a week or two of planting, or even within the first few days.

Germination usually happens underground, so we typically don’t witness this stage of growth. However, we can see the process of germination in the common practice of sprouting seeds for food.

Leafy Growth

As the plant continues to grow beyond it’s seedling stage, it will go through a period of leafy growth, building greater capacity for photosynthesis and harvesting energy from the sun.

As the leaves are growing above ground, there is a complimentary development of the root system which allows the plant to access moisture and nutrients deeper down in the soil.

Many annuals like lettuce and spinach are grown solely for their leafy growth.

In this case, the plants may never get the opportunity to develop onto later stages like flowering & seed production. However it’s important to realize that all plants will try to reach these stages of growth given the right opportunities.

Flowering

Annual plants have a very strong incentive to produce a lot of flowers in the shortest amount of time possible. This is again due to their short lifespan and desire to maximize the chances of reproduction.

In the case of cool weather annuals like lettuce & spinach, this process is triggered whenever the weather gets hot and dry.

The plant will “bolt” which means it sends up a stalk with lots of buds and flowers.

Fruit/Seed Generation

Other annual plants like peas are grown entirely for their fruit, which in this case is seed pods. These are harvested after the flowering stage, but before the seeds are ripe.

Plants produce hormones as their seeds get closer to ripening that tells them to stop making flowers, and to put their energy into completing the seeds.

In order for the seeds to ripen, they need to be left on the vine to dry out.

As you can see, the driving factor of growth stages in annual plants is being able to complete their entire lifecycle before running out of time in the growing season.

If the weather gets too cold before they get to spread their seeds, the plant will never get to pass on it’s genetics.

However there are other types of plants like biennials that adopt a completely different approach to moving through their growth stages.

Growth Stages In Biennial Plants

Biennial plants manage the challenge of reproduction by waiting until the second year to produce flowers and seeds.

This allows biennials to focus all their energy on building strong roots in the first year that ensures a more successful flowering and seed production in year two.

The following image shows 4 stages of growth in the life of a turnip:

• Year one covers germination, root development & leafy growth.
• Then there’s a dormant period during winter.
• And it’s followed by another year of growth the following spring to produce flowers & seeds.

Some common examples of biennial plants include carrots, turnips & parsley.

Simply observing how different plants move through these stages of growth gives you some amazing insider information about plants to help you identify, use & care for them more effectively.

If you notice a plant isn’t making flowers in a given year, this could mean it’s a biennial. Watch carefully and you’ll notice in year two the plant grows very fast and sends up a stalk that produces lots of flowers & seeds.

Growth Stages In Perennial Plants

Perennial plants are capable of living for very long periods of time. This means there isn’t such a big rush to reproduce in the first or second year.

As a result, here are several key differences to know about perennials:

• Perennials typically have much longer germination periods than annuals or biennials.
• They’re very sensitive to extreme weather while young, but can be incredibly tolerant of extreme heat & dry once established.
• Perennial plants sometimes spend many years just growing leaves & roots to get established before eventually producing flowers & seeds.
• Once a perennial is well established, their flowering period can sometimes last for much longer periods of time than annuals.
• Once pollination occurs, the fruits & seeds sometimes require much longer periods of time to ripen. (not always but it’s a common feature of perennial plants).
• At the end of the growing season perennials do not die, and instead will store energy for future growing cycles. This energy is stored differently depending on whether the plant is herbaceous or woody.

I personally love edible perennials because once you get them established, they’re very easy to care for, and often have much greater nutritional or medicinal content than annual plants.

It’s a great way to take care of nature while meeting your own needs for fresh, healthy food & medicine!

Herbaceous Perennials

Herbaceous perennials include common plants like clover, dandelions, valerian & peppermint.

A key thing to notice here is at the end of each growing season, herbaceous perennials store their energy in the roots for winter.

If you watch carefully as the weather gets cold, the plant will appear to completely die. All the foliage above ground will rot away, however the root zone is still alive.

Watch that spot in the following year and you’ll notice the plant grows back, often with even more vigor than the year before.

Woody Perennials

Woody perennials store winter energy in their roots and also in woody structures above ground. This includes plants like blueberries, raspberries, thyme & grapevines like this one:

These above ground structures are a huge advantage for woody/shrubby perennials because they can restart growth next spring starting where they left off.

More Tips & Exercises For Observing Plant Growth Stages:

When you start opening your eyes to these 8 stages of plant growth, you’ll be amazed at just how much easier it is to observe plants as unique individuals.

Studying growth stages will make your plant identification much sharper and more intuitive, while also helping you gain a more natural instinct about how to use and care for your local plants.

To get started, all you have to do is head outside for a plant walk and practice observing the different stages of growth in your local area:

• How many different stages of growth you can find?
• Can you find a plant at every stage of growth?
• Which plants are currently flowering?
• Can you find any with seeds on them?
• Are there any plants that only have leaves on them?
• Which plants are the farthest along in their growth stages right now? Why do you think that is?
• Can you find and compare examples of annual, biennial & perennial plants at a variety of growth stages?
• Which month do different plants leaf out, flower & make seeds or fruit in your area?
• Are there any plants that you can’t identify? What stage of growth are they currently in? Make a note of the location and monitor so you can come back and observe that plant in other stages.

The biggest trick is to always keep observing and ask good questions about your local plants every opportunity you get!