Being able to tell whether or not a flower has been pollinated is a valuable skill that anybody interested in growing plants should have at their disposal, regardless of what you’ve got growing in your garden. Pollination is an essential step in the process of how new plants are grown and can also affect the characteristics of the plant that you may wish to control.
To tell if a flower has been pollinated, look out for these signs:
- The presence of pollinating agents.
- Pollinated flowers begin to wilt.
- The ovule of the flower shows swelling.
- Seeds appear in pollinated buds.
- Your flower will change color.
Understanding the signs of pollination will allow you to control which plants flourish and which you wish to prevent from spreading into unwanted garden areas. Please read on to discover the classic signs of pollination to help you achieve your gardening goals.
1. The Presence of Pollinating Agents
Plants have evolved and adapted over the years to form symbiotic relationships with the natural world around them. This symbiosis has allowed many plants to develop relationships with animals where the animal benefits from some resource (usually nectar or other nourishment) and, in turn, helps spread that plant’s pollen to other plants.
You can see these natural processes at work in your own garden to get an early indication that pollination has taken place. Look out for bees, hummingbirds, butterflies, and other common pollinators as a sign of pollination in your garden.
Certain pollinators tend to be drawn toward specific types of plants. For example, bright flowers with tubular shapes attract butterflies, while beetles prefer dull white or green flowers with a sizable bowl-like shape.
You can also plant flowers that attract pollinators to encourage pollination in your garden.
2. Pollinated Flowers Begin to Wilt
One purpose of plants’ bright-colored flowers is to attract pollinators to help the plant reproduce. Once this process has occurred, the plant no longer needs the flower. The flower will begin to wilt, so the plant no longer needs to maintain it to use its energy and nutrients efficiently.
Wilting occurs relatively quickly, usually within 24 hours of pollinating the flower. What this stage of a plant’s reproductive cycle looks like varies from plant to plant, but you should be able to notice the plant’s flowers diminishing after pollination.
3. The Ovule of the Flower Shows Swelling
Identifying the different parts of a flower so that you can look for signs of a change is another good way to determine whether or not a plant is pollinated. Flowering plants go through visible changes after pollination, so once you know what to look for, you can know whether or not a flower has been pollinated.
Look for the ovule, which is the part of the plant in the inner part of the flower that will develop into a seed after fertilization. Once pollination occurs, the ovule will begin to swell as a sign of the early stages of seed development.
4. Seeds Appear in Pollinated Buds
Pollination ultimately leads to the plant growing seeds to reproduce and spread their offspring in the same way that humans and other animals do, albeit by a different process. Once pollination occurs, seeds will form as the culmination of the plant’s reproductive cycle.
The exact time frame for when seeds develop after pollination varies from plant to plant. Some seeds may be outwardly visible, while others are contained inside buds the plant forms around them for protection. Temperature changes can cause seeds to emerge.
5. Your Flowers Will Change Color
Along with the primary signs of fertilization and the appearance of seeds, pollination causes other changes in some plants. This change is due to senescence, a process that ultimately leads to the death of a bloom.
The color changes affected by pollination can affect the whole flower, or they can be localized according to the type of pollinators that frequent the plants. Color changes are typically due to the presence of the water-soluble pigment anthocyanin, which occurs in 68 families of flowering plants.
Flower species are particularly adept at using color changes in pollination. One flower, the Desmodium setigenrum, can even change color repeatedly if the initial pollination is unsuccessful. The color reversion signals pollinators that the flower is open for business!
If you’re growing vegetables, you should be aware that the flavor of some vegetables, such as lettuce, changes once seeds have begun to form. For example, framers often leave carrots to go to seed before being harvested for the changes in flavor this creates.
How Do Plants Become Pollinated?
Now that you’ve seen the signs of pollination in a plant, you may be wondering how pollination occurs in the first place.
Here are some pollination strategies that plants use in their reproductive process:
Self-Pollinating Plants
Pollination is how male and female plants reproduce to create fertilized seeds. Most plants come in male or female variations and have to use some method to get pollen from one plant to another for fertilization.
However, some plants grow with both male and female reproductive capacities to circumvent this issue by pollinating themselves. Sometimes referred to as ‘perfect plants,’ these plants are among the easiest to grow.
Many vegetables fall into this category, including:
- Broccoli
- Beans
- Onions
- Other commonly-grown crops
Because these plants need no external forces for pollination to occur, they can flourish without much intervention on your part.
Animal Pollination
As we previously discussed, many plants rely on a symbiotic relationship with the animals around them to pollinate other plants of their kind.
Animals such as bees and hummingbirds feed off of plants and get pollen attached to them. When they fly to another flower to feed more, they bring that pollen with them to facilitate the plants’ reproduction.
Planting flowers that attract these pollinators can help the health of your garden. You should also ensure that any fertilizers, pesticides, or other products in your garden aren’t harmful to bees or other pollinators.
Growing a pollinator-friendly garden will positively benefit all the plants you grow, not just the ones you plant to attract pollinating animals.
Pollination by Wind or Water
Other natural forces can also assist with the pollination process. Pollen is light enough to be carried on the wind from one plant to another.
Many plants take advantage of this, using airborne pollen in their seeding process. Plants of this kind will cross-pollinate simply by being close to one another.
A small subset of plants also pollinates through the water. Currents in the water take up the pollen and carry the pollen downstream to other plants to further the cycle of pollinating new seeds. These tend to be aquatic plants that aren’t common in a garden.
Manual Pollination
Along with letting natural processes occur to pollinate your plants, you can also step in and manually facilitate pollination yourself. This process will take some guesswork out of wondering whether or not pollination has occurred since you did it yourself.
Once you’ve manually pollinated the plants, all you’ll need to do is wait for seeds to form.
In some cases, you can achieve this straightforwardly by carefully rubbing the male and female flowers together to cross-pollinate the two. You might also use a paintbrush to delicately take pollen from one flower to another.
If you are wondering how to pollinate indoor plants, this article is for you: How to Pollinate Indoor Plants (8 Easy Methods)
Final Thoughts
When you understand more about how your plant’s reproduction works, it can help you become a better gardener. Pollination is one of the essential processes in a plant’s life cycle. You can encourage a plant to flourish by seeding or preventing pollination in cases where you don’t want seeds to develop.
Whether your plants are self-pollinating, pollinating using animal vectors, or require manual pollination is an important consideration when planning your garden. In the case of plants that pollinate with the help of animals, having a pollinator-friendly garden is the best way to encourage your garden to flourish.
