You can if you like extract the seeds from your own tomatoes, as demonstrated in the video link I have provided. Essentially once you have the seeds from tomatoes they are no different to any other garden seed and the process of propagation is much the same as for any other plant.
You cannot grow plants with seeds taken from Hybrid tomatoes however, see the comments section for an explanation of why.
- Use ripe, reasonably fresh seed that has been stored in a cool dry place
- Use a proper seed compost for best results, a loam based seed compost is generally the best
- Maintain a good level of cleanliness both of the compost (keep in sealed bags) and of the seed trays
- Fill the seed trays to within 1/2″ of the top rim by pressing in your seed compost, level it off and firm it down by hand
- Mark the tray if necessary so you know what you have planted
- Moisten the compost before starting to sow so that it is exactly that moist, not dry or waterlogged
- Push the seeds into the compost to a depth equal to their diameter or thereabouts, tweezers might help with this process.
- Don’t sow everything at once stagger over a week or two to give you plants at different stages of development to give yourself some options for a longer growing period
- Make sure the seed is lightly covered, then water in with a fine mist of water from a sprayer.
- As with watering tomato plants you need to maintain a watering program that ensures the seeds don’t end up dried out or waterlogged
That is pretty much it, you can help the seeds along by covering with a sheet of white paper and a piece of glass or slipping the seed tray into a polythene bag to help retain moisture. The paper stops the condensation going straight into the seed compost.
After 2 – 3 weeks the seedlings should be large enough to handle without damage and should then be transplanted, using tweezers or a thin plastic or wooden strip with a V notched out to prise out the root ball. Try not to handle the stem, hold the plant by the first leaf.
Use a dibber to make a small hole in the compost and put 2 to 3 seedlings in a 3″ pot ready to grow on. Leave them now to grow on until large enough for planting in the ground or some kind of container, vine tomatoes usually do best for the final stage if they are planted 2 or 3 to a 40L grow bag or 1 per 12″ pot, other than that of course you can prepare the soil and plant your tomatoes in the the ground and for short summer regions this should probably be in a greenhouse.
Remember before final planting check the plants over and discard any that are weak, stunted, distorted or where the leaves are pale or mottled, these are the ones most susceptible to disease and liable to failure at the final stage.
*Top Tip* the ideal germination temperature for tomatoes is 16C (61F)