lenght times width equals square footage. Easy chart is
1 =12 inches apart
4= 6 inches
9= 4 inches
16= 3 inches apart per sqft

You can take the spacing off of the seed packet.
6 inches aprt=4 per sqft
leaf lettuce
dwarf marigolds
parsley
basil

9 per sqft = 4inches
bush beans beets

16 to a sq 3 inches apart
carrots
radish

Watch your depth of the container for root crops and bigger plants (tomato), you can use bigger containers for tomato plants.

If you get Mel's book on sqft gardening, there is a chart for spacing more plants.

Hope this helps

Stan

kawaiineko_gardener, I've read Mel's All New Square Foot Gardening book, and I'm going to try to incorporate the SFG method with container gardening. I can't build 4x4 boxes as he suggests, my back yard is too small. But I'm going to try to use his spacing suggestions to use the pots I already have and place them around the patio/porch.

For example, leaf lettuce needs to be 6 inches apart, I'm going to measure a 6" square and plant a lettuce seed/plant in the center of that square. I don't want to go buy all new containers, so I'm hoping this will work.

Any luck with your attempts? Anyone else tried this?

Yes, it's the spacing I use in my containers. As et14 said, it appears to be the same recommended seed spacing that's on the seed packets. Of course, it isn't easy. Most of my containers are round, so I have to eyeball it a little.

The information you posted just tells me how much to plant per square foot, it doesn't tell me how many square feet are in my container.

Regarding checking out a book on the New Square Foot Gardening book, I have done so in the past. All he really does is specify how many square feet are in his specific containers, not give a general guideline for how many square feet are in containers in general. Essentially all he does is give the dimensions and square footage for his planting system. Since I'm not using his planting boxes, but rather the method itself, this doesn't help me.

Thank you for the information and for taking time out of your schedule to post it. Unfortunately I'm aggravated the information given wasn't the information I asked for and I still don't have my original question answered. I'm sorry if this comes off as rude; I'm not trying to instigate a fight.

Telling me how much can be planted per square foot gives me good planting guidelines for container gardening, but this information is useless to me if I don't know how many square feet are in each of my containers.

Somebody also told me that when it comes to volume (which they said can be applied to my containers) the formula for square footage can't be used with volume because the square footage formula is used for area, not volume.

That formula is what ended up confusing me in the first place since it can't be used for volume, since square footage is used for area, not volume.

Can you please just tell me how many square feet are in my containers like I asked for in the first place. I apologize if I come off as rude, but it gets extremely frustrating when I ask for specific information and people give me information that is helpful, but not what I asked for.
This is the information that was given to me in regards to the square footage of my containers. Unfortunately they converted it using a formula I don't understand. If somebody could please give me clarification as to how they converted the dimensions of my containers from inches to what they gave below (from inches to feet) then I would appreciate it. This makes no sense to me; I'm really really bad with math, when I try to understand it, it just ends up confusing me.

If people here are good with math fine. However don't assume that because you're good with math, it should be the strength of everybody else around you. Such is not the case with me.

19" div. by 12" = 1.58' and
14" div. by 12" = 1.16'
1.16' X 1.58' = 1.832 sq. feet. Call it almost 2 sq. feet.

You can do the basic math on all of them but all your listed containers are 2 to 4 sq. feet. The last one on your list is 4.28 sq. feet.

Try this:

you have a box (container) that is 2 feet by 4 feet.
you do 2x4 which equals 8 squares.

Take your container:
18 gallon container
Length:23"
Width: 17"
Depth: 15"

ok let's do the square foot the easy way, length is 23 inches rounded off to 24 which will equal 2 feet. Now your width is 17 inches rounded off to 18 inches which will equal 1.5 feet. Take your length (2 feet) times the width (1.5 feet) and you get 3 square feet. take this a multiply times your square footage.

Now let say you want to do radish which would be 16 to a square or 3 inches apart. Just take that times the number of squares you want to do.

Thing to remember it does not have to be exact. I think you are getting footage and volume confused. Volume comes into play for root crops and larger plants. Let's say a tomato plant, some people say one plant one square foot. Five gallon bucket, one tomato plant or maybe 2 per 18 gallon tote.

If you go by Mel, he says 6 inches most things. I do 12 inches in most of my beds so that I can do root crops. Potato plant, I build up from there.

If you need more help. list the plants you want to do

hope this clears thing up for you

Stan

Anything that involves math confuses me; that's why I hate math.

Somebody told me to find the square footage of something you do this. First you find the area, which is length x width.

Then you convert your product to square footage by dividing the product by 144 (since 1 square foot is 1 foot by 1 foot; 12"=1 foot; 12 x 12=144).

Using one of my containers as an example...

The 10 gallon one:

19" x 13"=247 inches

247 divided by 144=1.71 square feet.

Is this formula/method for using square feet that I posted correct?

by golly, I think you got it!!!!!!!!!

Two other questions and then I'll leave you alone. I'd like to attempt to grow root veggies in 1' x 1' boxes (one variety per box; in one box turnips, in another kohlrabi, in another carrots.....you get the idea).

However what would the depth of the box have to be for root veggies? My daikon (long asian white radish that takes longer to mature) will reach 2-3 feet in length. The carrot I plan to grow will be 6"-8", the turnip 2" across in diameter, and the kohlrabi variety I'm growing is 2"-3" in diameter.

I won't just be putting the box on the ground then digging a hole and placing it on top of the hole; that is I won't be growing the stuff in the ground, I don't have that kind of space for gardening. The box will have a bottom. Sorry I can't be more specific with the length of the kohlrabi and turnip, but it only specifies how big the bulb (root portion) of it gets with the diameter.

My 2nd question is if a box is has half a square foot, then can I use that half square foot to grow stuff, or will it be overcrowding the container?

Example....

My box is 1-1/2 square feet....I want to grow red radishes in the box. You can plant 16 radishes per square foot; however since I have half a square foot that possibly means I could grow 24 radishes (16 for the square foot and 8 for the half square foot; 16 + 8=24). So would it be feasible if I have leftover space or would it overcrowd the container?

Also for radishes, it only specifies red radishes for growing using square foot gardening. Would I be able to grow the same amount of Asian radishes per square foot as red radishes, or since they're bigger, would I reduce the amount that can be grown in that space? Basically since it's a radish, just bigger and takes longer, could I grow 8 asian radishes per square foot?

When the guidelines were given initially for the spacing of the boxes, that's referring to how far apart you'd space each square foot if you're container has more than one square foot, correct?

This is what I mean....

1 =12 inches apart
4= 6 inches
9= 4 inches
16= 3 inches apart per sqft

Is that referring to how far apart you space the vegetables per square foot or how far apart you space the square feet (if there is more than one square foot in your container). I'm just a little confused because the person who posted that never specified if that's how far apart you space your boxes (per square foot) or how far apart you space your veggies in the square foot.

I realize how far apart you space the veggies in your square foot depends on the veggie being grown correct?

For how deep, it depends on the plant. What you are talking about, carrots radish....etc, I say your box should be at least 12" deep or more if you want. Tomato plants need more (like the 18 gallon tote you were talking about). I would say at least 12".

Spacing, you have got it right. Just remember if its 4", it's 4" in all directions. All you have to do is stagger your rows.

Most of the time if you growing from seed it will have the spacing on the packet, just use the spacing and forget about the row.

I think that you are off to a good, have fun!

Stan

I think you may be overthinking some of this and confusing yourself. Believe me, I understand, I do it all the time.

For your box that is 1 1/2 sq ft - from what I understand, yes you can plant the additional 1/2 sq ft either in the same plant (radishes) or in something else that would fit there and not be contraindicated for the radishes.

For your bigger radishes, and for all vegetables, look at how far the seed package says to space the plants from each other. That is the same spacing you will use in Square Foot Gardening. Red radishes call for 3 inches apart, which translates into 16 per sq ft. If the bigger radishes call for 4 inches apart, you would plant 9 per sq ft. Just don't pay any attention to the row spacing on the package; we do away with that here.

That being said, I hope your next question has been made a little clearer now. The spacing you referred to:

1 =12 inches apart
4= 6 inches
9= 4 inches
16= 3 inches apart per sqft

is for the spacing between plants. In Square Foot Gardening there is no spacing between the squares at all (unless you want to for design, yard shape, or appearance reasons). For example, in a standard square foot garden (4ft x 4ft) there are 16 squares. All you do is somehow draw a grid by attaching string, boards, or some other straight item at every foot across and down the box.

Since you appear to be talking about containers, I guess you are wanting to know if you can place your containers right next to each other. I think the answer would be yes. The only considerations there would be having enough space to get to each plant and making sure that incompatible plants are not right next to each other. (you wouldn't want to shade low plants with taller plants) These are the same considerations you would have if you were building a standard box.

I hope that helps a little.

Okay to address the first question, which is what would the depth need to be for 1' x 1' boxes. When you said it depends on the plant, here are the varieties I have.

Hakurei Turnip (an oriental white radish that matures quickly) the bulb reaches about 2"-3" across in diameter when it's ready to harvest

Golden Beet-The diameter of the bulb will reach about 2" across in diameter when it's ready to harvest.

Red Radish-Basically it's an elongated, cylindrical variety; a French breakfast variety that is 2" long and 3/4" wide when it's ready to harvest.

Carrot. It's an early maturing nantes variety that will reach 6" to 6-1/2" in length when it's ready to harvest.

Kohlrabi. It's your typical pale green variety, and it's early maturing. It will reach 2" to 3" across in diameter when it's ready to harvest.

I'm wondering if it's possible to grow daikon radishes in containers? By daikon, I mean the large white oriental varieties; they take longer to mature then red radishes are longer with their length.

I was thinking of growing varieties that are typically between 10" to 16" in length. Somebody told me a general rule of thumb for the length of root veggies is that the depth has to be twice as much as the length of what you're growing (if you're growing a radish that is 2" in diameter the planting depth has to be 4"....this is just an example).

Could I use this rule for growing daikon in containers?

Also thank you very much for the clarification with how to find square footage for a rectangular container.

However now I need to know how you find the square footage of a circular container. By circular container, I basically mean a round pot/planter (the kind you typically find in the gardening section of Walmart, Lowe's etc.)

I do not do well with math at all, but if you explain how to find the square footage of a round container in a simple way, that I understand, then I'll be able to figure out how to calculate using the square footage formula given. Just don't speak in math jargon please.

OK depth first,

For root veggies, I go at least 12 to 16 inches deep. again it depends on the veggie. Carrots need lots of depth.

Round containers,

How about making a cross across the top of the container and finding your center. Let's say that you want to plant radish. You look on the seed packet and it says to have 3 inch separation between plants.

Start with one in the center of your container, and then move out from there by 3 inches. As long as you can keep the separation going just keep adding.

There is a math formula

The formula is A=pi*r2 , where pi = approximately 3.1416 and r is the radius of the circle (length of a straight line drawn from the center to the outside edge of the circle. The area is pi times the radius squared.

example 10 inch round container
radius would be 5 inches.
5*5*3.1416=78.54 square inches/144 inches=.545416 sqfoot (about a half sqfoot)

Here is a link that might be useful: Square footage of a circle