Most mainstream advice on tomato care includes the recommendation to prune out tomato suckers.  Suckers are those little leaf growths (little in the beginning, anyway–they can get huge) in the axil of the tomato plant. The axil is the name for the joint where the branch meets the stem.

Here’s a pic of a tomato axil:

Here is a pic of a tomato axil with a sucker growing out of it:

Some pooh-pooh sucker pinching, saying they never do it and they have lots and lots of great tomatoes. That’s fine.  I know one of my own brothers belongs to this school, and we’re still on perfectly good terms.

I tend to sucker-pinch.  I have a smaller garden and raised beds, and have more need to keep things well under control.  Here’s the logic behind sucker-pinching, as I understand it:

While suckers will grow into branches that can produce fruit, allowing them to grow unchecked may lead to a tomato jungle.  The problem with a tomato jungle is that it can get out of control.  It becomes harder to keep the plant off the ground and maintain airflow around the plant to prevent disease.  If you do have to battle disease, it’s harder to treat successfully. It’s also easier for hornworms and aphids to get a foothold because you can’t examine your plants as closely, and it’s harder to harvest the fruit.  The plant may produce more tomatoes, but some of them are likely to be smaller and of lower quality.

An exception is determinate tomato plants.  Determinate tomatoes reach a certain size and stop and begin to mature fruit.  They are not going to become jungle-like in the first place, so you can let all the branches go ahead and do their thing. If your tomato variety is called “bush,” or “patio,” or something denoting small size or container growing, it’s probably determinate.  It will also probably say so on the label.

To help first time sucker pinchers, I made a short video.  I’m posting it as a laugh. I’m terrible at this, so the beginning of the video shows me talking about part of the plant that is in the extreme left corner of the shot (or not at all).  I tried to re-do it, but I went all to pieces and believe it or not, this was the best take.  Think of it as a How-Not-To-Make-A YouTube-Video Video.  Hopefully I’ll learn how to hold the camera properly before I try this again.

Here’s the link.  I apologize in advance: http://youtu.be/UD6oUi0857g

Note: The first plant in the video has a large sucker above the one I trimmed (off camera) that’s gotten so big I’m letting grow as a second leader. The rest of them I’m planning to keep trimmed.