Why the Hot and Humid weather in the Gulf hurts our plants?

As summer is settling here in the Gulf the daytime temperatures hover around 42 degrees Centigrade or108 degrees Fahrenheit. The humidity is also on the rise, going northwards from 70 o 80 % most days. While most of us have heard that our beloved plants need a certain amount of humidity we do see that our plants wilt and die during the four months of summer. Why does this happen and why does the high humidity make our plants struggle? There is a very scientific reason for this and this is why we need to be careful about watering and the shades in summer. In the summer it is very hot and temperatures during the day hit 46-48 degrees centigrade quite often even in coastal areas. The air is still and laden with moisture and hot moisture at that. Imagine sitting in a boiler room all day and night, that is how our plants feel. Some people advise having a fan to circulate air around but I have not tried that. Remember to give as much space as possible between the plants and not crowd them together. This avoids crown rot as well as the spread of mealy bugs etc among your plants. Now for the reason why our plants struggle – Just like we perspire, plants transpire. They let put excess water through their stomata(pores) and cool themselves down. This also is the process that delivers the nutrients from the soils to the tip of the leaves. When the humidity is high the plants cannot lose excess water by opening their pores and letting the water out. Two things then happen. The plant is not able to draw nutrients through the soil as the pressure is not enough to pull the water up as it is not perspiring(transpiring). Also, rot and fungi attacks cause the plant to wilt as the moisture stays in the plant body. Plants will wilt and have yellowing leaves showing signs of root rot and overwatering. Basically, they drown and starve. As I have always said in earlier articles and comments, you will need to water less in the summer when humidity is high and the plants are shaded as the water does not evaporate. So, check before you water

Make sure you aerate the soil regularly and add cinnamon powder to your pots as that will get rid of the ants and therefore mealy bugs. It also reduces the number of fungal attacks on your plant. If you give your plants a shower make sure you do it only about twice a week to remove sand and salt deposits so that the stomata are not blocked.  Some experts advocate deep watering once in three days to ensure the plants get the correct amount of water.

Here is a great video that explains the concept well.

And another simple but very good article that explains the process well.

https://sciencing.com/high-humidity-effects-photosynthesis-12060330.html