Does anyone here know of a table that shows pot size inches/gallons? Example Wallmart sells standard 15 inch pots but some people say they are 7 gallons and some say 5 gallons. I am horrid at math and this confuses me so.
Thanks for your help
Gallons/ pot diameter
The volume depends on the pot diameter but also its height and how it tapers down (are the sides straight, or is the bottom of the pot much narrower than the top). The plain old black pots that you get things in from the nursery may be standardized a bit more in terms of height and tapering, but the pots you are buying at WM, HD, etc are going to vary quite a bit from one pot to the next. So you could have a 15 inch diameter pot that's 7 gallons and another one that's 5 gallons because of differences in the other dimensions.
The pots I speak of are the "standard" pots you can just about get anywhere. If there was some reference to just say a 10 inch pot is a 3 gallon pot or whatever that would make things so easy.
Clay pots?
No plastic
There just has to be a site that has it. I'll search tomorrow morning.
http://www.noveltymfg.com/retailers/retPrPatio.html
It's probably not what you wanted but it's all I could find so far.
Thats better than most of the stuff I have found looking myself. Thanks. You're a gem to take your time to do this.
You can try this one but I find it confusing: http://www.botanical.com/botanical/cvsoilix.html
Plug the drain holes, get a measuring cup and start pouring water in it until it fills up. Don't go by any set rules because you will be sorely disappointed. As ecrane says you have to take in the taper and the height of the pot as well.
The formula if you really want to know it is:
Volume of a cylinder = PI * Radius ^ 2 * Height
where PI can be rounded off to 3.14 and the caret symbol denotes raising a
number to a power
Since this is a tapered pot you will have to get the average radius or diameter. To get the average diameter measure the inner diameters of the top and bottom since the thickness takes up some volume (don't measure the outside unless you subtract twice the thickness).
The average diameter would be:
Avg_Dia = (Top_Diameter + Bottom_Diameter) / 2
Radius = Avg_Dia / 2
Measure the height vertically from the floor to the top (not along the taper!)
So now you can calculate the volume but this would be in cubic inches.
Convert it to cubic feet by dividing by 12 ^ 3 which is 1728 CI in one CF
There are roughly 8.5 gallons in one cubic foot so multiply the previous number by 8.5
So if you had a 15 inch pot that was 13 inches high (vertically) and the bottom diameter was 12 inches it would hold:
3.14 * ((15 + 12) / 2 / 2) ^ 2 * 13 / 1728 * 8.5 ~ (roughly) 7 gallons
Alrighty then
I was wrong on the gallons per CF and the calculation too. It is almost 7.5 gallons per CF instead of 8.5 therefore the gallons in the pot example would be roughly: 8 gallons. The calculation on the first example should've come out to around 9.2 gallons to boot. Goes to show you that calculations are too much work for potting purposes - just eyeball it and keep it simple.
http://www.google.com/search?hl=en&q=gallons+in+a+cubic+foot
Amen to that. Your first post made my brain hurt.
Thank you ever so for the help though, seriously.
Generally, what is sold as a 1 gallon container, is about 6 to 6 1/2 inches across. This is called a "trade gallon". If you calculate the cubic inches of this container, you will find that it is not really a full gallon, but this is what's sold in the trade as 1 gallon. ( A gallon is approx. 231 cubic inches.) What is sold as 2 gallon is about 8 inches across. 3 gal. is 10 inches. 5 gal. is about 12 inches. 7 gal. is 14 inches
1 gallon = 6-6½ “
2 gallon = 8”
3 gallon = 10”
5 gallon = 12”
7 gallon = 14”
10 gallon = 20”
If you can read the name and any numbers on the bottom of the pot I might be able to give you exact numbers
Rev thanks ever so. EXACTLY what I needed.
Krnbrohl no need but thanks (they are in the garage and I have snow up to my ears right now).
Don't thank me, I found this somewhere some years ago, probably on Garden Web. I printed it up and put it on my bulletin board so I can always refer to it.
I just wrote down the information. Thanks, Revclaus.