Hello everyone welcome back to the podcast hope you're having a good day.

Today we are talking about the effect of artificial lights on plants so we know in nature you have a natural rise and fall of light levels

throughout the year. Summer solstice of course is the longest day of the year

but in the world of plants that also is the longest day of the year but in the world of plants that also is the shortest

night and as the summer keeps going the days get shorter and the nights get longer.

If you are a temperate plant, they understand. They see what's going on and at a particular

ratio of light to dark, there will start to be a change to prepare for the dormancy of winter.

Now there are plants that need an uninterrupted dark period.

They need it to be dark when it's dark and not a little bit light.

And that helps it prepare for winter,

but there's also certain plants that that helps initiate flower buds. So the harsher the winter, the earlier those changes are going to happen

and those native trees can go ahead and get cold-hardy and prepare for dormancy so they can

survive the winter and then they come back.

Now what's interesting is you see trees in urban environments, trees that are lining streets,

etc, they're going to be exposed to light for much more than a say a rural tree on the side of the road

would because of artificial lighting and street lights in the city.

So what happens then is the leaves, the buds nearest to the source of light are going to say oh I guess

summer isn't ending I guess it's keeping on and and I don't need to prepare for dormancy. I don't need to initiate

buds and flowers. So it's pretty hard to see if you're just watching day by day, but as the weeks and months go on, you can see,

oh my gosh, some of these plants just really aren't turning.

You know, fall isn't happening to some of the plants and there's actually a really crazy

picture of a plant that is right next to a streetlight specifically azer

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