How do plants know when it’s time for flowers to bloom?



How are they able to determine the time of year and when to bloom or shed their leaves?

In: Biology

Some plants do so based upon how much light they get. Other plants flower based on conditions in the growing medium and environment (nutrients, temperature, moisture, weather conditions etc.).

Some do so purely based on their genetics and time alive.

This is the simplest way I can answer this without getting technical or into specific plants.

Edit: A couple typos

They don’t, they are just reacting to external & genetical factors.
See, as a human, you are growing up following the big plan in your DNA, and the nutrients from your food, and other stuff, the same goes for the flower.
There is no time in life where you think, humm, this week would be a great week to grow up.

It’s usually based on the length of the day/hours of sunlight. As the days grow longer or shorter throughout the year, this activates signals in the plant to grow, bloom, shed leaves, etc.

That’s why you can influence… *certain* plants to flower indoors by manipulating the light cycle from something 18 hours (“summertime”) down to like 12 hours and make them flower.