Why do plant leaves turn red?

In autumn many plants turn red

Image – Wikimedia Commons / Jorge Franganillo

How come some plants turn red when fall comes? And why are there others who do it at other times of the year? The truth is that the reason will depend a lot on the season in which we find ourselves, and on the state of health of the plant itself.

So I think it is interesting to explain them so that, in this way, you can know Why do plant leaves turn red?and whether or not something needs to be done about it.

It is his reaction to the drop in temperatures

The red of the leaves usually appears in autumn

The red of the leaves usually appears in autumn

Or what is the same: it is autumn, it starts to get cold, and then little by little it stops feeding those leaves. Why? Because If I kept feeding them, if I kept sending them sugars and starches from the roots, when frosts came I would suffer a lot.: not only would it lose the leaves, but it would also have to expend energy closing the buds -which is where the foliage sprouts from-. And no matter how fast she is, she couldn’t help but have a bad time. In fact, I would venture to say that you could lose even the most tender branches.

But how come they turn red? This is due to the pigments they have in the leaves.: the main and best known is the clorofila, which is what makes them look green, but they also have carotenoids and flavonoids, including anthocyanin. Well, the first to start producing less and less is chlorophyll; For this reason, the other two, although their production also drops, does so at a slower rate.

Now, we would be short if we left it here, because, yes, the cold is a reason, but… why do some have red leaves and not another color? Well, American researchers discovered that this is due to the amount of nitrogen in the soil where they are growing If it is poor in this nutrient, the plants will tend to produce more red pigments.such as anthocyanin, so that as chlorophyll is lost, the red pigments will become more exposed (here! you have the link to the discovery).

He is very thirsty

If we have a tree that turns red in the fall, but is very thirsty in the summer, its leaves may turn that color prematurely.. Of course, this will only happen if the soil, in addition to being dry, is poor in nitrogen, as we have just discussed.

But although a red plant is very pretty, It is important that we water it if it is thirstyespecially if we have it in a pot since that is when the substrate dries much faster than the garden soil.

They use red pigments to protect themselves

Cordyline fruticosa requires little careCordyline fruticosa requires little care

Image – Flickr / barloventomagico

There are several plants that are red, or partly red, all year. For example, him Cordyline fruticosa of red leaf, or the Fagus sylvatica lime atropurpurea (red leaf beech). There are even succulents that, as a consequence of continued sun exposure, end up with the tips of their red leaves, like the but the palmers.

Japanese maple turns red in fallJapanese maple turns red in autumn

Related article:

10 plants with red leaves

Well, these are not like that because of the cold, but because of the Sun. And it is that what the red pigments do is protect the leaves from ultraviolet rays, and also prevent them from producing free radicals -these are unstable molecules that, when produced in large quantities, damage other molecules, accelerating aging-. So the more anthocyanins and other red pigments they produce, the longer they can last. But does this mean then that we have to protect green plants? Nope.

The plants, each and every one of them, are genetically prepared to grow either in shade, in semi-shade, or in full sun. Regardless of the color of its leaves, it is important that we know where to place them so that they grow correctly. Of course, we will have to be more careful if we have one that has to be exposed to the sun, but it had never hit it before, since not being used to it would burn it. In this specific case, what we would do is put it in semi-shade, and slowly and gradually expose it to the sun.

As you have seen, there are three very interesting reasons why plants can turn red at some time of the year.

Why do plant leaves turn red?

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