Your math is correct. I think planting green beans 3 inches apart is on the close side - and would recommend six inches myself. At six inches, you would have 30 plants.

If you plant in rows, you probably can get by with "double rows" - meaning that you can plant two rows of green beans with spacing between the rows at six inches and spacing between the plants at six inches. This would effectively give you 60 total between the two rows. The area that would take up would be a 1-foot by 15-foot area.

Here is a link that might be useful: My Garden Blog

Well, it really depends on how much of something your household is going to use. Personally, I think those kind of blanket statements are pretty meaningless. If I planted a 30 foot row of bush beans, it definitely would not give me anywhere nearly the enough I like to freeze every year for my household of 4 and the other 4 people I do a lot of freezing and canning for.

I guess I can't really offer you a lot of suggestions -- its' going to be mostly trial and error. All I'm trying to say is take those general guidelines with a grain of salt.

Thank you for clarification. This below is just for clarification. I'm horrible with math, so I just want to make sure that what I provided with the information is correct. I don't trust myself at all with math, that's why I'm asking.

So basically if something says you plant 'this much in a row' for container gardening, in order to figure out how much to plant, you'd use the formula I gave below? That is, you convert the feet to inches, then divide the inch measurement by the plant spacing, and the quotient is how many plants you plant?

I don't know if this will help, but you might try thinking in terms of square feet, since most pots would come closer to representing one to one and a half square foot. If you do it this way, think like this:

If you want a fifteen foot row of beans planted four inches apart (that's the spacing I use), that means that you could grow 3 plants per foot in each direction (length times widith), or 9 plants per square foot. So, if you are planting in a fourteen inch diameter pot, you could plant 9 seeds. You might be able to squeeze a couple more around each of the four "edges". Fifteen feet of row would contain 45 plants (3 per foot), so you'd need 9 square feet of growing space, or 9 pots, give or take.

It will be very important to keep your potting mix charged with fertilizer, especially if you grow this intensively. I used to grow veggies in pots. I would charge the pot with osmocote at planting time AND feed with a liquid fertilizer every other week, or at half strength every week. Needless to say, consistent watering is equally important.

To know how much you really need, I would start with approximately the amounts you were given, keep great records, and then in a year or two, you'll know what YOUR family needs.

This is why using all the info provided by Sq. Foot Gardening has already been suggested to you in several of your posts over the past several months.

Sq. Foot Gardening, tons of info about it on the web, has already done all the conversions and calculations for you. It tells you exactly how many of every kind of vegetable to plant in each of your containers. All you have to do is measure the width and length of your containers, multiply the width by the length to determine the number of square feet, and then plant. We even did the math for you on several of your containers.

However whenever I post there, I'm treated like I'm an idiot whenever I ask a question about gardening; as a result I avoid posting there unless I have no other choice.

Yes, your posts do belong on that forum but I agree that some of them have run out of patience with you. That is because you keep rehashing the same issues over and over and over again. It isn't nearly as complicated as you make it out to be so why does the tipic require 8 different posts?

I also have given you links to online garden planners (linked the easiest below again) where all you have to do is type in the length and width of your container and it will tell you exactly how many beans plants, or turnips, or lettuce, or rutabagas or anything else to plant in the container.

If you have a 1 sq. foot container you put in 4 bean plants, 2 sq. foot, planter gets 8 plants, etc. No math to do, no conversions, no complications.

Dave

Here is a link that might be useful: Garden Planner