Growing tomatoes with tomatoes is possible. This is how it's done..
Cut slices of a tomato. Not just slices, but slices where the centre of the tomato is in the middle. So that you have a ring of seeds..Put potting soil in a container. I used the container where cherry tomatoes were in.
Let them grow till they reach a length of 15 cm or 6 inch. They will not all grow till plants. Than put them in a bigger container.
Dont forget to use some organic fertilizer.
In 11 weeks after sowing you can expect your first flowers
And than it's waiting for the harvest. Depending on the size, weatherconditions you can get your first red tomato 6 weeks later.
Enjoy!
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From @adriaan66