Moisture Meters

[BenToken]

I would like to ask everyone's opinion on Moisture meters. Do they work? Are they specifically soil or will they be accurate with a soil less medium (ie...Coco Coir) I just ordered one (Amazon Add-On Item) it comes in this Thursday. I thought it would be a good idea as I have seedlings started in 5 gallon Smart Pots. I don't want to over-water them. (Number 1 reason noobs like I kill their babies). These are my last 2 auto seeds and I really did not want to transplant them nor kill them.

 

[SiriusFourside]

I've never used a moisture meter when I've grown in coco and I don't think many people do; a Google search doesn't turn up much either. When it comes to watering, I use the same rule as Nebula: water until you see 20% runoff, wait until the top inch of coco is dry and water again. It's not as exact as using a meter I would guess, but it does work very well!

If you're worried about killing seedlings, try starting your seeds in Rapid Rooters. Rapid Rooters will give you a great buffer so your seedlings won't dry out too fast or stay too wet. Plus, with a Rapid Rooter all you really have to do is make sure to not constantly water or let them completely dry out.

 

[ZigZag]

I got a moisture meter for my first grow_ saw it the store and thought it might be a good idea...sound familiar? Anyway after using it for a month or so I haven't used it much since. It measures moisture at different depths so you can get an idea of how moist it is at say 3,6 or 12 inches. But watering when the top inch of coco is dry does the trick, just follow Nebula's formula. When growing in coco I usually just feel the top inch and lift the smart pot to see how heavy it is. If it feels heavy but is dry on top I feel the bottom to see how wet it is. The 5 gallon smart pots sit on top of a grid that fits inside the tray so the bottom has air circulating all around the entire pot. I used the meter once to confirm how wet the bottom was...the leads weren't long enough to get to the bottom so I had to poke a hole on the outside about an inch from the bottom and push the meter in from there. It did go all the way to "wet" so I waited and watered the next day. But I would have done the same thing even if I didn't have the meter, unless the plant showed signs of being thirsty. Pay attention to your plants_ they will tell you what they need. GWE provides all the info you need to interpret plant language_ I would have been lost without it!

 

[BenToken]

Thanks for the tips. I did a good watering last night and the meter will come in today. I guess I will use it more of a statistical item instead of relying on it.

 

[Flockshot]

I have only had 3 grows and have used 2 moisture meters. Personally, I have little faith that I can water properly using a meter. I found a 'yard sale' scale that goes up to 25 lbs and now use that to measure the water content of my pot.

I charged 6 gallons of ProMix HP with one gallon of water (8 1/3 lbs water weight) and then used 1/2 gallon of water to 'water in' my transplant (4 1/6 lbs). So I know that I have 12+ lbs of water in the pot. The total weight of the pot was 22 lbs.

If I weigh the pot and it comes in a 14 lbs, I know that one gallon of the water has left the pot. I am not saying that this is the correct amount of water for the plant (I think it is too much) but want to give an example of how to determine the amount of water in my pots.

After lifting the pots onto the scale for a entire grow I can get a 'feel' for the weight I am looking for and hope to stop using the scale. Reading that the pot should be 'light' is open to interpretation and I got it wrong. I felt that if the leaves never droop from lack of water, and the pots were 'light', that is was doing a good job watering, but a root autopsy after the grow indicated significant under watering with all the best roots in the bottom half of the pot (top half too dry for good roots).


My warning to a first time grower is to not UNDER water and do not UNDER feed, as I did.

Peace

 

[Weed Pharma]

I use a moisture meter, mostly because you can get root readings.
The meter spent a couple of grows in a drawer, as I did not think it was accurate.

I was determined to find objective signs when watering was needed/where it was needed. SO:

I drilled a hole in the side of the bucket about 4-6" from the top to stick the meter in so the meter accessed the root ball or bottom 1/3 of the container.
Whenever I get a reading of #2 or below- I then lift the pot- and that determines if watering is needed- or another day is needed.
This has worked for me incredibly well. Keeps me from overwatering and also easy in adjusting for changes in temp/humidity in the grow tent.

Now, as far as the pH accuracy- Not at all- always reads between 7-8.