How to prune cordon tomato plants
For cordon varieties, the first step in pruning is to extract foliage near to or touching the ground.
Yellow or diseased looking leaves will also need to go, as well as any covering developing fruit.
Gardeners should do this every two weeks or so. Then, remove any stems growing upwards rather than out from the main structure.
Any of those not growing at a right angle, whether old or new, will require removal.