General Question About Watering

[King's Indican]

hi! I have a rising question in my mind i try to explain.
im using biobizz light mix and nutrients in 8 liter air pots. currently having afghani and blueberry autos.
lights turn on at 7 pm so i go check them they seem droopy because they were in dark for hours. in an hour or so they rise again. sometimes they dont then i lift the pot feels very light and i water them. they usually spend the night little droopy due to watering and i think biobizz needs more time then organo mineral nutrient solution. but sometimes both the plant look happy and the pot feels light. so I cant decide . this plant 25 days old looks very happy and light at the same time. should I water it? how much of the soil should be dry for next watering?

look at the plant behind that looks droopy. it was very light and i watered it and it doesnt come back immediately as opposed to mineral based nutrients.
what am i doing wrong?

 

[Creeperpark]

I don't think you are doing anything wrong. Plants respond to water in different ways. Plants will droop before and after watering without any major causes. You want to have wet-to-dry cycles so the plants can get water and oxygen equally. Now if you water and the pots are heavy and the plants are drooping its because of water exposure. If the pots are lightweight and drooping then it is from excess oxygen exposure. You need both worlds for a plant to respond productively. It's normal for a plant to droop before and after watering. If you get your timing set where the plants have dry and wet times everything will be fine. if the old leaves turn yellow then too dry. Heres a before and after droopy plants on watering day.

 

[Creeperpark]

Its very important to know exactly how much water your containers of soil hold before ever planting your seed. If you know how much water it holds then you will know how much to give without over or under-watering.

For example I have a 3gallon pot of soil that holds 3 liters of water when completely dry. Now I only give them 2 liters on a watering day because one is still in the container. Knowing how much water the pot holds is key to water management.

 

[Creeperpark]

Roots need oxygen, too!
In the ground, air and water are held in little pockets called soil pores. If the soil is dense and compacted (with no soil pores), there will not be enough oxygen available for respiration. Too much water in the soil will also limit the amount of oxygen the roots can take in. Google

Lastly, I would rather have a few older yellow leaves from under-watering than over-watering root damage. Watch the plant leaf petiole because it will tell you a lot about the turgor pressure.

Turgor pressure is best known in plant cells but also occurs in walled cells of other organismal kingdoms. The build-up and maintenance of turgor pressure requires five key components: water, solutes, a selectively permeable membrane, a wall and metabolic energy. Google

 

[Creeperpark]

Here are the same plants after 30 days. I'm using 3 different size containers in this grow. I'm using two different soils that have different water-holding capacities which require 3 and 5-gallon pots. Since I know exactly how much water each container holds I can better manage the plant's water and nutrient requirements without a lot of waste

 

[Creeperpark]

Watching the humidity is becoming a crucial part of watering now that the flower tops are set. When the calyxes swell and have fewer minute leaves they become dense, and the water transpiration slows almost to a stop. There are almost no stomata in the buds for the water and gas to exchange. Water will get trapped in the stems without an exit when plants are watered too much. And with extra outdoor wet weather, I need to be very observant of the amount of water I give the plants.

 

[Creeperpark]

Out of the six plants, 3 are not taking in much water and 3 are needing more water every day. Knowing this I can better manage my water intake without over or underwatering. If I watered them all at the same time with the same amount of water I would run into problems. Water management is best when each pot is watered individually and not all watered in a group.

 

[Creeperpark]

The outdoor humidity is staying very high for many days in a row. The indoor growing environment is in the high 50s and low 60s hitting 70 for brief moments. My growing environment houses many houseplants as well, so the air and dew point are very high. All I can do is limit the water transpiration on all my plants and vent the wet air out. I'm only giving the plants enough water to stay alive. 1 liter per day. When the wet weather changes into dry conditions I will give all the plants full watering with a little runoff to rehydrate them.

 

[Creeperpark]

The most crucial factor in horticulture success is water management. That's where it all starts and where it ends.

 

[LungCooking]

Great Topic! Well done

 

[King's Indican]

thans for amazing answers. I succesfuly finished that grow and got some blumats to use with next grows.