A plant requires a combination of several factors to ensure optimal development. Light levels, carbon dioxide in the environment, the humidity present in the air, as well as the water and the amount of nutrients in the substrate, among others, must reach a particular balance that adapts to the particular requirements of each species and that largely replicates the characteristics of the plant's place of origin. The productivity and successful survival of your plants depends directly on this; but there is one element that is often overlooked: temperature.
Whether it is hot or cold, whether it is summer, winter or spring. All these environmental changes are perceived by the plants, which adjust to it, affecting their appearance and performance. While this is much more obvious in plants that produce fruit, changes can also be seen in houseplants and foliage. Not all plants respond in the same way to temperature, this depends on their origin and species, so we will explain in detail the importance of temperature for plants, how it affects their well-being and even what is the ideal temperature for them.
The importance of temperature
When it is very hot or cold, humans and animals have the instinct and the option to protect themselves by seeking shade, cooling off with water or seeking shelter. Plants cannot do this, they are static beings. This makes them a little more vulnerable to sudden changes for which they are not adapted and to some extent makes them a little more dependent on us. But don't think that they are completely passive in the face of these environmental changes.
The temperature issue is not a trivial one, as plants develop according to their circadian clock; an internal biological control that allows them to regulate their physiological life processes to occur at particular times of the day and according to the seasons. Each species has its own rhythm, its own clock, suitable for adapting the plant to the climatic characteristics of its environment. Species native to one region have no problem and require no extra help to fulfil their life cycles because they are prepared to withstand the temperature variations of their region, but if you take it out of this space and into another, it will have problems. In fact, this is a major dilemma in the face of global warming, as abrupt temperature changes are negatively affecting native species.
This biological clock is the reason why each plant species has particular temperature specifications. For example, a Prunus Serrulata or Japanese Cherry tree can withstand temperatures ranging from -18°C to 45°C as these are the typical seasonal temperatures in its country of origin; but a Prunus Serrulata or Japanese Cherry tree can withstand temperatures ranging from -18°C to 45°C as these are the typical seasonal temperatures in its country of origin.but a mango tree must live in a tropical climate of 20°C or more, as it originates from India and that is the minimum temperature in those regions. If I take a Japanese cherry tree to a tropical country there is a slight chance that it will survive (it would be a miracle) but it will not bear fruit or flowers because the tree needs to overwinter in order to accomplish these processes.
Ambient temperature vs. plant temperature
The environmental temperature is a determining factor for the development of certain biological processes of the plant, as it will allow it to determine what season it is in and if it is the ideal time for it. Many processes are accelerated with high temperatures, as it lets the plant know that it is in summer and/or spring and that it is time to grow or produce fruit, for example. It is in these seasons that the perfect combination of environmental factors takes place, which will make fruit production easier and more optimal for the tree.
The temperature of the plant is a different factor and although it is confused with the environmental temperature, they are not necessarily the same. Plants are living beings, so they have certain tools at their disposal that allow them to regulate their temperature. If the external temperature is too high, it can be cooled by evaporation, and if it is too low, it can be heated by irradiation. Like humans, plants have an optimum personal temperature. In humans it is about 37°C, while many trees and plants have an internal temperature of about 21°C, as indicated by a study by the University of Pennsylvania. This does not vary, regardless of the external temperature or the species of tree.
In warm conditions, tree leaves release water, which cools as it evaporates from the surface. It is a process very similar to the sweating of human beings. Plants can also move their leaves at angles that allow them to be less exposed to the sun's rays. In colder climates, trees often close their leaves, preventing heat loss. These processes will allow it to reach that perfect temperature of 21°C, ideal for photosynthesis and other functions necessary for its survival.
However, each part of the plant has a different temperature because it relates differently to the environment. Thus, the fruits of a tree have a temperature very similar to the ambient temperature but will not fluctuate as quickly. Flowers have a higher temperature, because the petals do not transpire as quickly and efficiently as the leaves. The leaves of the plant may also have different temperatures as the lower leaves will be a little cooler than the upper leaves, which receive more sunlight. This makes the regulation of the internal temperature of the plant a complex process, which will be affected by the external temperature.
In order for a plant to reach this perfect internal temperature, there has to be the right relationship between ambient temperature, light and humidity. If there is too much sun, the plant will overheat and will have to invest more resources in order to regulate itself. The plant's metabolism speeds up, demanding more water and more mineral nutrients. If these high temperatures are maintained, fruiting plants will speed up their production and their yields will be affected.
How to know the ideal ambient temperature for plants
Although different plant species have different requirements depending on their origin, you should know that the temperature should oscillate during the day and night, as there are processes that occur during certain times of the day. For example, the transport of sugars occurs during the night and goes to the warmer parts of the plant to facilitate growth and development. This does not happen randomly, because plants have the ability to sense temperature variations during the day. This process is called thermoperiodism and is responsible for the growth, flowering and development of the plant.
Experts are able to use this ability to control plant growth, causing certain morphological characteristics. For example, it is known that a combination of high temperatures during the day and low temperatures at night stimulates stem growth. Without going too far, this is the principle of greenhouses that allow us to have food production all year round, regardless of the season or seasons, as these conditions are artificially simulated.
That said, the ideal temperature for plants should be as close as possible to their place of origin. There is no perfect temperature, in fact it must vary naturally in order to stimulate the plant to carry out certain vital processes. What must be respected is the range of each type of plant. There are more rustic species, which will adapt easily to almost any climate. In fact, there are some that behave like deciduous plants in places with distinct seasons but like perennials in tropical conditions.
Perfect temperature for houseplants
The vast majority of the plants we use for indoor decoration are of tropical or Mediterranean origin, so they will be happy in environments where the temperature is between 15-24°C. The good news is that humans need to be in an environment with a more or less stable temperature, which is usually within this range thanks to technological marvels such as air conditioning and heating.
Indoor plants may also require moderate amounts of light, as they are semi-shaded, although some species tend to require high levels of humidity. These are aspects that you must take care of so that the plant can fulfil all its processes. There is no point in creating a warm environment if there is little humidity, for example, because this will prevent the plant from transpiring or growing. Maintaining a plant is almost like having an orchestra play a song, as all the instruments must complement each other in harmony. In case you are wondering if your plants are in the right temperature environment, pay attention and look for these symptoms.
Symptoms that the temperature is incorrect
- No plant growth or development.
- Flowers wilt too quickly. This is a symptom of too much heat.
- The leaves of the plant look droopy or turn yellow. This can happen because the temperature is too cold or because it has received cold draughts.
- The leaves at the bottom of the stem fall off. The others look wilted and/or have brown edges. This may occur because the temperature is too high.
- Dry leaves and parched substrate. This may be because it is too hot and the plant has started to dry out.
Aspects that affect the temperature of houseplants
While you can't control the climate, you can improve the conditions in which your plants live indoors. Small things can make a big difference to the life of your plant, especially when combined with balancing other elements such as humidity, light and watering.
Heating and air conditioning
The problem with heating and air conditioning is not the temperature, but that they tend to dry out the air too much and rob the plants of moisture. For this reason you should place plants away from the appliances and take measures to ensure that the plants are receiving the humidity they require.
Pay attention to watering
When it is very hot you run the risk of over-watering to compensate for the temperature or you do not adjust your watering patterns according to the season. The problem is that inside your home you don't get the same amount of sunlight, so overwatering is likely to affect the roots, drowning them or causing rotting.
Remove plants from the windowsill
The windowsill is a great place to put planters and pots because they get plenty of light and warmth in spring and summer. But if you are in a place with distinct seasons, you should remove plants from the windowsill in winter as frost can affect them. Move them a little further away from the glass and they will be fine.
Avoid sudden changes in temperature
Most plants tolerate temperatures below or above their ideal limit very well, but the problem occurs when these changes occur suddenly. Sto will cause a thermal shock to the plant. This applies not only to frost and the like, but to young plants that have been raised in semi-shade and will be moved to full sun or outdoors. It is best to acclimatise them slowly.
Beware of dra ughts
Your plants may be happy and protected indoors, but if they are in a draughty place (near a window or door for example) they will start to have problems such as leaf loss and wilting. Keep them away from these places and make sure they are not exposed.
Dedicated to creating an army of cacti, succulents, poodles and cats to help me conquer the world. In the little free time I have left, I play, write and dance.