I planted tomato as an experiment. I wanted to see if they would grow, and set fruit indoors, but it is becoming obvious that I will need to do some trimming as I don't have the space they require.
This article is short and simple. It describes the method of trimming indeterminate tomato plants in order to produce a better quality crop.
Basically the method involves breaking off the suckers in order to direct the energy to the main stem.
Other sources indicate that these suckers can then be propagated and grown as individual plants which will space out the peak production over a wider time.
Some may disagree with the use of a knife or shears, opting to break the suckers off because it is less likely to cause infection and spread disease.
If the suckers continue to grow back it is important to continue breaking them off. In addition to breaking off suckers some also recommend topping the plant near the end of the growing season in order to let the last few tomatoes mature and ripen.
How to Trim a Tomato Plant | Garden Guides