Examine the skin color of the fruits about 10 weeks after planting They are likely almost completely red at this point. Gently squeeze a couple of tomatoes to ensure they are still firm. If some are soft, pick them now; hot weather is to blame for their softness. Otherwise, continue to care for the tomatoes until the fruits are uniformly red.
Harvest "Park’s Whopper" tomatoes when the skin is uniformly red and the fruits are still firm when gently squeezed. Grab tomatoes and pull and twist them to remove them from the vine. Store tomatoes in a shady, cool area, ideally between 45 and 50 degrees Fahrenheit.
Check the tomatoes still on the vine every one or two days so fruits do not over-ripen, reducing their quality. Pick and store ripe tomatoes. If frost is in the forecast, harvest unripe tomatoes and store in a shady area that is kept at 50 to 70 degrees Fahrenheit for one to three weeks until they fully ripen.