[omits]

They say you should transplant a plant as deep as possible. Does this mean I should/could replant my tomato plant in the same pot again when it has reached say 6 - 8 inches? Thanks.

[JayG]

Depends - if you sowed it in a small pot the roots will probably already have reached the bottom.

If you sowed in a large pot you probably could re-pot deeper in the same pot - you don't want the roots to be sitting at the bottom of any pot after transplanting (they need room to grow downwards.)

(This works for tomatoes because they so readily produce new roots from buried stems - it certainly doesn't apply to all plants.)

[Subversive_plot]

Specifically with tomatoes, for a plant that has reached (roughly) 6+ inches tall, I will set the root ball of a plant on a 2-inch mound of soil in a larger pot (3-gallon size) and then bury the plant with soil, compost, or a mix of both up to the seed leaves. That usually only fills the pot 1/4 to 1/3 full with rich soil.

Let it grow a 2 or 3 weeks in that.

It will quickly root into that soil.  After it has grown some more, bury the stem a little more in rich soil, another 2 or 3 inches. 

More growth will happen. keep repeating the process.  You will get a plant with a prolific root system.

[omits]

Well how interesting! Like potatoes then. Does this mean there are more tomatoes or longer season? I guess though that the plant is better able to support it's crop. I have put my seeds in big pots to start off with so to do this I will have to remove it and half the soil (say) and build it up as you suggest but as JayG says not too near the bottom. Thanks I will try this on one of my plants (probably the Manzano).

[Aunt Sally]

If you’re planting your young plants in the ground (indoors or outdoors) you can plant them horizontally under the soil with just the top leaves above the ground.  Roots will form all the length of the buried stem.

[Subversive_plot]

Well how interesting! Like potatoes then. Does this mean there are more tomatoes or longer season? I guess though that the plant is better able to support it's crop. I have put my seeds in big pots to start off with so to do this I will have to remove it and half the soil (say) and build it up as you suggest but as JayG says not too near the bottom. Thanks I will try this on one of my plants (probably the Manzano).

Similar to what would be done for potatoes, yes (you probably know, they are related).

Rather than getting more tubers, with tomatoes you are indeed trying to develop better roots, and better support, for the crop.

Best of luck with your tomatoes.

Sub_p