Posted: 09/05/2014 at 08:30
The Alicante are what's known as determinate (or in our house - the tall ones that need staking ). Here's how I understand it.....the side shoots, if left, will eventually produce flowers and fruit but it takes the plant a lots of extra energy to grow these side shoots and then the flowers and fruit. This means the first lot of fruit may take longer to grow and ripen, and given the shortness of our summer times you may end up with a lot of green tomatoes (I know this from experience and I have a lovely recipe for Mangoish chutney made from green toms if you ever need one!). If you remove these side shoots, the plant can concentrate its energy on the flowers and fruit that grow from the main stem and you'll have tomatoes sooner and hopefully most of them will have the chance to turn red.
With the tumbling ones, these are known as bush tomatoes and they wont have one main stem but lots of branches, so you don't pinch these out, jut let them get on with it.
Hope this helps - took me a while to get my head round it too, I don't know if I've got it right yet but it seems to work for me. My main advice is don't worry about it - just go with the flow. If it doesn't quite work out - call it an experiment and have another go next year!