I've been looking into container gardening for vegetables and I'm trying to make sense of container sizes. Several books refer to a barrel or half-barrel but I haven't seen anything labeled "barrel" and the store.
With vegetables is the volume of the pot more important or the depth?
For tomatos I've been told I can use an 8 in deep window box. Another source said a 10 or 12 inch diameter pot should be fine. Someone else said to plant 3 tomatos in a huge 24 inch diameter pot. I'm so confused about how big a container I really need. I just can't seem to find any consensus on what size pots I need for tomatos (or peppers or peas or radishes for that matter). I don't want to use something too small, but the thought of the cost for all the soil required for 6 or 7 of the 24" diameter pots is scary
I'm curious as to what y'all have used before and what results you got.
For root or tuber veggies (e.g. carrots and potatoes), you will need a deeper container. A 4 or 8 gallon garbage can with drainage holes punched in the bottom will work fine.
For above ground plants (lettuce, tomatoes, etc), I believe that space around each plant is more important. That's where the half barrels come in handy. They may not be labelled as "barrels", but they will be wooden (or a wood substitute such as plastic) made of individual staves held together by wire hoops. Any garden center that sells containers for plants should carry the half barrels. If you can't find them or the cost is prohibitive, resort to the 4 gallon garbage can, and use 1 per tomato plant.
The 10 - 12 in diameter pot will be adequate for one tomato plant; I'd use a taller container of this diameter for tomato plants to keep it from being top heavy and tippy. 2 or 3 tomato plants can fit into a 24 in container comfortably. 4 tp 6 pepper plants ccan probably fit into the same size container. Every year, I plant about 10 to 12 basil plants into a 24 in container, and could probably squeeze in a few more. You can crowd things a little bit more into a container than you can in the ground.
The shallower the container, the more often you will need to water. Plastic holds water the best, then wood, and unglazed terra cotta loses the most water through evaporation (great if you're growing succulents!)
