Basic rules for giant tomatoes depending on growing conditions:
1. It is approximately 80 days from transplanting in the garden to harvesting a tomato.
2. It is approximately 70 days from the pollination of a blossom until harvesting a tomato.
3. Prune off all open small tomato blossoms except one in each cluster.
4. Prune off all blossoms after tomato set completion.
5. Prune off all secondary vines (suckers) except one until tomato set is completed.
6. Allow no secondaries to grow above tomatoes after they have set.
7. Top all tomato plants at 6 feet.
8. Six weeks before harvest, each plant should be down to 4 tomatoes, and at 1 month before harvest, each plant should be down to 1 tomato.
Below: this plant has been pruned to allow only two vines to survive. All but one seconday, or sucker, has been pruned away. The sucker will be topped at four feet and the main vine allowed to grow.
Below: note a plant that has been completely trimmed of leaves to show the one main and one secondary pruning method.