Mark, the modified mix Al recommends is a good place to start, but are you planning on covering the container and relying upon a strip of fertilizer on the surface to feed the plants? This is critical because if you will use the cover/fert strip you really need a fast wicking potting mix and this means peat and vermiculite. What I often tell people getting started with Earthboxes where a cover and fertilizer strip will be used is that the system was designed with peat based mixes and it works very well with them so give that a try for a year. It will give you a good frame of reference for tinkering in subsequent years. Assuming you do not wish to do this then: I would encourage you to make a mix and set it outside to see if it will keep the surface moist for a couple days before committing. This is if you will use the cover and fertilizer strip. If you won't use either then Al's mix (original or modified) will work fine. Keep in mind my experience is in Wisconsin, somebody in a hotter/drier/windier climate might need to modify a bit. Even with the cover on, the wind gets under it from the holes we must cut for the plants. This wind may not seem like much, but it can quickly dry the surface. You really do need to test though, that's the best approach. Just do it outside. I say this because I made the mistake of evaluating how well various materials wicked *inside* (I was going through an endless winter and wanted a gardening 'project'). How something wicks indoors is waaaay different than how it wicks outside due to temp, wind, humidity etc. Again though, you really only need to modify Al's mix with fast wickers like vermiculite or peat if you want to use the cover and fert strip. One last tip, if you find that the very surface goes and stays dry, but an inch down it's moist you can simply bury the fertilizer strip an inch under the surface. This gives more latitude in compromising between a coarse mix that drains well and one that can wick fast enough to keep that fert strip working. Happy growing.

My primary concern is that you are starting awfully late in the season to be growing from seed. Nah.... plenty of time to grow a fall garden from seed. How about less tomatoes and incorporating a variety of other vegetables. Not everyone loves tomatoes and tomato plants are the least aesthetic of all vegetable plants to most people. Check with your state's Extension Service. Each county should have it's own Cooperative Extension Office which provides free publications and information for the asking. They will have valuable vegetable/gardening tables available specifically for your area determined by universities and horticultural research scientists who have collected data from growing those crops in your state. Your tax dollars are already paying for this service so you may as well get some use out of it. Vegetable Planting and Planning Calendar for Missouri (download the pdf) complete with spring and fall planting dates (underneath the spring planting dates for appropriate crops), how much to plant per person, etc. They can also tell you the average last frost date for your area and ideal planting times for specific crops and varieties in your area. See how detailed this example is:

I tried the bucket method this year. Took lots of cuttings potted some up immediately and then tried the b o' brug method I saw here. My bucket b's made roots in the bucket but when put in the ground....nothing. My potted b's going great since transplanting. What did I do wrong?

romy6, Phildeez, When I stress pepper plants it involves holding back water... letting them wilt for a bit before I give them some water. The nutrient stressed Berbere in the pic was just another problem (not planned) in a season fought with problems a few years ago. The Berbere was only one of 15 out of 200+ starts that survived after a Thrips attack. Then things got worse LOL. Sometimes ya just gotta roll with what nature dishes. At least I got a decent harvest of Berbere. I dried and powdered it for use in some Ethiopian recipes - yum. Bill