San Marzano Plants wilting after transplanting

Question

I planted my San Marzano plants outside in containers last weekend. After 3 days, 4 of the 6 plants are wilting. They have all received enough water. I’m not sure why this is happening. Any ideas?

Answer 1

Were the plants hardened off from the greenhouse prior to planting out in the garden?
This is an important step that sometimes we try to skip when we are hurrying to get our gardens planted.

https://www.gardeningknowhow.com/garden-how-to/seeds/when-to-transplant-a-seedling-plant-into-the-garden.htm

Since you have all ready planted them out continue to make sure they are receiving adequate water.
You can try to shade them during the heat of the day to help them recover.
It's possible the plants may not recover and sometimes it's best to move forward with new plants.
Here is a link to proper planting techniques.
I personally love to remove lower leaves and plant my seedling down quite deep. This will help the plant grow nice strong roots and stems.

https://www.gardeningknowhow.com/edible/vegetables/tomato/planting-tomato-plants.htm