Water from Above or Below

[OlderStoner]

Long ago I read a book on growing cannabis and the author said they prefer to water their plants from the bottom. I still marvel at how a pot filled with potting soil will soak up lots of water when you let it stand in a basin of some kind with just a couple of inches of water in it. Provided it's got some holes in the bottom of it or it's just porous.

Yesterday, for the first time in three grows, I let some of the 6" pots set in a basin with about 1" of water and in about 45 minutes the soil was soaked from top to bottom. The moisture could be seen from the top. This would seem to me to be a better way to deliver water to the plant because you're getting the entire medium wet without flushing it. Of course I have good drainage and the water is taken up by the plant or evaporated within a few days. I know that cannabis likes to dry out now and then to get it's roots going deeper so I'm not trying to flood them. And I prefer to let my plants get almost to the point of wilting before I give them water. And I'm amazed at how long they go with the pots feeling very light and the soil dry. The growth is good even with the dry soil.

The only drawback I see with it is that later in the plant's life, it's not always easy to lift it and get it into a basin or even the bathtub. When the plants get bigger and they are in bigger pots and full of water, lifting and moving them is harder than one would think. I like soil grows so I think one day I will design and build the perfect trickle up and then down system that requires only the opening and closing of valves rather than moving 35 - 40 lbs of wet potting soil into the bathtub and back.

 

[Fuzzy Duck]

Plant pot dishes/saucers big enough to hold flower pot may help...


Also they is a system called Autopot which is based on a gravity feed res with the pots sitting in tray like thing with a valve to allow flow of water/nutrients to X level before shutting off to prevent flood... not seen very many people use this system tho !

 

[Growdad420]

Above the way god intended. Watering from the bottom makes no sense to me since it doesnt happen in nature, I am not sure why or how this would be a good idea. But if you do intend on growing this way I would love to read and see your grow journal. Good luck.

 

[Roy Growin]

Above the way god intended. Watering from the bottom makes no sense to me since it doesnt happen in nature, I am not sure why or how this would be a good idea. But if you do intend on growing this way I would love to read and see your grow journal. Good luck.

Roots grow down because that's where they expect to find water, so perfectly natural
So long as the frequency and quantity are correct, top or bottom watering is not really a question
The real benefit of top watering is that it draws in more oxygen to the root zone

 

[Emilya Green]

I am totally against the idea of bottom watering and would never even consider abusing my plants in such a way. I consider it an inferior and lazy person's way of watering our plants. Even most commercially available commercial auto watering setups, do it from the top.

Weeds have a top set of roots that will not be done any favors with this method, getting their only water for just a small window of time from that which manages to seep up through the soil. You also totally lose control of the water cycle, having no idea how much water your plants are using and therefore you also have no idea how good or bad the roots may be. It is nearly impossible to build a rootball in the entire container using this method, so very large producing plants are hard to create. Stagnant water in the grow area is always a problem and this method requires it. Gnats would no doubt have a field day in that room. Constantly wet soil can be a huge problem and you will have to take care to avoid dampening off, molds and mildews. Lastly, how in the world do you get oxygen into the roots using this method without also oxygenating this water pool?